Bennett and Schumacher’s postselected quantum teleportation is a model of closed timelike curves (CTCs) that leads to results physically different from Deutsch’s model. We show that even a single qubit passing through a postselected CTC (P-CTC) is sufficient to do any postselected quantum measurement with certainty, and we discuss an important difference between “Deutschian” CTCs (D-CTCs) and P-CTCs in which the future existence of a P-CTC might affect the present outcome of an experiment. Then, based (...) on a suggestion of Bennett and Smith, we explicitly show how a party assisted by P-CTCs can distinguish a set of linearly independent quantum states, and we prove that it is not possible for such a party to distinguish a set of linearly dependent states. The power of P-CTCs is thus weaker than that of D-CTCs because the Holevo bound still applies to circuits using them, regardless of their ability to conspire in violating the uncertainty principle. We then discuss how different notions of a quantum mixture that are indistinguishable in linear quantum mechanics lead to dramatically differing conclusions in a nonlinear quantum mechanics involving P-CTCs. Finally, we give explicit circuit constructions that can efficiently factor integers, efficiently solve any decision problem in the intersection of NP and coNP, and probabilistically solve any decision problem in NP. These circuits accomplish these tasks with just one qubit traveling back in time, and they exploit the ability of postselected closed timelike curves to create grandfather paradoxes for invalid answers. (shrink)

Closed time-like curves (CTCs) naturally appear in a variety of chronology-violating space{times. In these space{times, the principle of self-consistency demands a harmony between local and global a airs that excludes grandfather-like paradoxes. However, selfexisting objects trapped in CTCs are not seemingly avoided by the standard interpretation of this principle, usually constrained to a dynamical framework. In this letter we discuss whether we are committed to accept an ontology with self-existing objects if CTCs actually occur in (...) the universe. In addition, the epistemological status of the principle of self-consistency is analyzed and a discussion on the information flux through CTCs is presented. (shrink)

Gödel’s contention that closed timelike curves (CTC’s) are a necessary consequence of the Einstein equations for his metric is challenged. It is seen that the imposition of periodicity in a timelike coordinate is the actual source of CTC’s rather than the physics of general relativity. This conclusion is supported by the creation of Gödel-like CTC’s in flat space by the correct choice of coordinate system and identifications. Thus, the indications are that the notion of a time (...) machine remains exclusively an aspect of science fiction fantasy. The element of the identification of spacetime points is also seen to be the essential factor in the modern creation of CTC’s in the Gott model of moving cosmic strings. (shrink)

In 1949 the great logician Kurt Gödel constructed the first mathematical models of the universe in which travel into the past is, in theory at least, possible. Within the framework of Einstein’s general theory of relativity Gödel produced cosmological solutions to Einstein’s field equations which contain closed time-like curves, that is, curves in spacetime which, despite being closed, still represent possible paths of bodies. An object moving along such a path would travel back into (...) its own past, to the very moment at which it “began” the journey. More generally, Gödel showed that, in his “universe”, for any two points P and Q on a body’s track through spacetime, such that P temporally precedes Q, there is a timelike curve linking P and Q on which Q temporally precedes P. This means that, in principle at least, one could board a “time machine” and travel to any point of the past. Gödel inferred, in consonance with the views of Parmenides, Kant and the modern idealists, that under these circumstances there could be no such thing as an objective lapse of time, that time or, more generally, change, is an illusion arising from our special mode of perception. For consider an observer initially at point P. At point Q he boards a time machine and travels back to point P, taking time t′′ to do so. In that case, according to his own clock, t′ – t + t′′ > 0 seconds have elapsed, and yet an identical clock left at P would show that 0 seconds have elapsed. In short, there has been no “objective” lapse of time at all. Gödel remarks that in his universe this situation is typical: for every possible definition of an “objective” time one could travel into regions which are past according to that definition. He continues. (shrink)

A-theories of time claim to best respect common sense, whereas B-theories of time typically eschew common sense and instead draw their inspiration from science, in particular relativity theory. For 100 years the battle lines have tended to be drawn over the existence of a universal present. Less prominently, but nevertheless well-known for the last 50 years, similar battle lines have been drawn over the possibility of closed time-like curves. In this battle A-theorists have argued (...) that closed time-like curves are incompatible with common sense and hence are impossible. In this paper I show how A-theory can be reconciled with the existence of closed time-like curves, albeit with some theoretical loss. I argue, however, that given that A-theorists tend to also hold that time travel would entail restrictions on free will, they might actually welcome this particular theoretical loss. (shrink)

The Kalam Cosmological Argument is perhaps the most solid and widely discussed argument for a caused creation of the universe. The usual objections to the argument mainly focus on the second premise. In this paper we discuss the dependency of the first premise on the topological structure of the space-time manifold adopted for the underlying cosmological model. It is shown that in chronology-violating space-times the first premise can also be violated. The chronology-violation, in turn, requires a massive violation of (...) the so-called energy conditions which might have observational effects that are briefly discussed here. Hence, astronomical observations could be relevant for the validity of the metaphysical argument. In this sense, it is possible to talk of “observational theology”. (shrink)

We show that quantum interference can be interpreted in terms of a phase invariant quantity, not unlike the Berry’s phase. Under this interpretation, closed loops in time become fundamental quantum entities, and all quantum states become periodic. Decoherence is then seen to occur naturally as a consequence. This formalism, although counterintuitive, provides another useful way of assigning meaning to quantum probabilities and quasi-probabilities.

In lieu of an abstract, here is a brief excerpt of the content:Being the DifferenceJake BeeryThat day started just like many others. It was a cold, wet day in March spent anxiously answering and reviewing hundreds of USMLE STEP 2 practice questions for my exam just a week away. Except that Sunday would be something different. Looking for any excuse to take a break from my personal mental marathon, I picked up a call from my dad. He had just (...) spent the past six weeks wheeling my mom to near-daily appointments at the Mayo Clinic for treatment of her metastatic ocular melanoma. But now, with them back home, I had hoped for a short reprieve in the story of her cancer journey—for me, and for all of us. Instead, I listened to him explain how, less than 24 hours after coming home, my mom would be entering a hospice house in our hometown. Unable to control symptoms by themselves, my parents made the choice they felt would be best.Left with more questions than answers, a day later I found myself on a red-eye flight touching down on a snowy Minnesota runway. Inside waiting was the rest of my family, whose happiness to see me was unmistakably weighted down by similar hours of lost sleep. Together we shared as much time as we could with my mom, grateful she was able to meaningfully communicate when most other tasks proved unbearable. And that would be how she passed, surrounded by her closest family. Gone was my mom, my best friend, and the one person who I felt truly knew what it meant for me to be in medical school.The days that followed flowed in a melancholic blur. While I felt I knew so much about the time before hospice through talking with my mom and reading too many Kaplan-Meier curves, I was lost in the reality of losing a loved one for the first time. But as support poured in, time seemed to ease up. A close family friend who worked with grieving families as part of their profession told me, "In times like these, people will say things that seem strange. That's okay. Just try to listen to how much they care." And listen I did, savoring the minutes-long escape of listening to stories of a life well lived. Each time doing so, I felt the pull from the unknown to a place of unfortunate familiarity. Without much reference to how life feels after the loss of a parent, I cautiously stepped forward to face the rest of life's chores thrown at me.First came the rescheduling of STEP 2, reworking my study schedule, and yet more practice questions. And with it came my first struggles. While prior to flying home I could answer and review over 150 questions on a good day, I found myself unable to complete more than a single 40-question block. Every ophthalmology, oncology, and critical-care question transported me from the realm of abstract patients back to the beige waiting room of the hospice house. Gone was the joy of memorizing medical minutia. Originally, studying filled me with a sense of pride, furthering my dream of becoming a physician just like my mom had unintentionally inspired me to be. But now I didn't feel any of that. I despised every minute spent with my laptop open. But knowing the weight of board exams on a medical trainee's life, I pushed on. Outside of UWorld questions, I tried to make my world as normal as it once had been. I went on runs, got cappuccinos, and sat with my best friends. I did all the non-urgent things that still felt so important. And while I still [End Page 70] desperately missed my mom, multiple-choice questions gradually got easier, and the second chapter of my medical school career came to an uneventful close in a stuffy suburban testing center. And with it came my return to the wards.As a now 4th year medical student, I was set to begin a month-long rotation on the inpatient palliative care consult team at a busy, tertiary care medical center. As usual, the first day... (shrink)

ABSTRACT Closed time is possible in several senses of ‘possible’. One might like to know, therefore, whether closed time is possible in the sense that it is compatible with standard metaphysical theories of time. In this paper I am concerned with whether closed time is compatible with A and/or B theories of time. A common enough view amongst philosophers is that B theories do but A theories do not allow closed (...) time. However, I show that prima-facie neither approach allows closed time, but that with a little work standard versions of both approaches do. This shows that there’s no special problem with the notion of eternal return. (shrink)

Relativity allegedly contradicts presentism, the dynamic view of time and reality, according to which temporal passage is conceived of as an existentially distinguished ‘moving’ now. Against this common belief, the paper motivates a presentist interpretation of spacetime: It is argued that the fundamental concept of time—proper time—cannot be characterized by the earlier-later relation, i.e., not in the B-theoretical sense. Only the presentist can provide a temporal understanding of the twins’ paradox and of universes with closed timelike (...) curves. (shrink)

Notoriously, the Einstein equations of general relativity have solutions in which closed timelike curves occur. On these curves time loops back onto itself, which has exotic consequences: for example, traveling back into one's own past becomes possible. However, in order to make time travel stories consistent constraints have to be satisfied, which prevents seemingly ordinary and plausible processes from occurring. This, and several other "unphysical" features, have motivated many authors to exclude solutions with CTCs from (...) consideration, e.g. by conjecturing a chronology protection law. In this contribution we shall investigate the nature of one particular class of exotic consequences of CTCs, namely those involving unexpected cases of indeterminism or determinism. Indeterminism arises even against the backdrop of the usual deterministic physical theories when CTCs do not cross spacelike hypersurfaces outside of a limited CTC-region|such hypersurfaces fail to be Cauchy surfaces. We shall compare this CTC-indeterminism with four other types of indeterminism that have been discussed in the philosophy of physics literature: quantum indeterminism, the indeterminism of the hole argument, non-uniqueness of solutions of differential equations and lack of predictability due to insuffcient data. By contrast, a certain kind of determinism appears to arise when an indeterministic theory is applied on a CTC: things cannot be different from what they already were. Again we shall make comparisons, this time with other cases of determination in physics. We shall argue that on further consideration both this indeterminism and determinism on CTCs turn out to possess analogues in other, familiar areas of physics. CTC- indeterminism is close to the epistemological indeterminism we know from statistical physics, while the "fixedness" typical of CTC-determinism is pervasive in physics. CTC- determinism and CTC-indeterminism therefore do not provide incontrovertible grounds for rejecting CTCs as conceptually inadmissible. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Anthony Close CENTERING THE DE-CENTERERS: FOUCAULT AND LAS MENINAS Over the last two decades, French avant-garde critical theory has shaken the pillars of the traditionalist temple with this thought: the interpreter of a literary text should not primarily be concerned with its author's intentional design, but rather with the surreptitious forces which shape it, warp it, and ultimately turn it into a problematic will-ofthe -wisp. The "decoding" of those (...) forces takes many forms (Freudian, anthropological, and so on), of which deconstruction is the most celebrated ; "de-centering"—the banishment of the intentional subject from the focus of interpretation — is common to all. In the first part of this article I wish to set out my philosophical objections to that exclusion, and in the second part, to examine an interesting failure to make it effective in practice: Foucault's analysis of Velazquez's painting Las Meninas, which constitutes the first chapter of Les mots et ks choses. One of my reasons for choosing Foucault's text as an example is that its premises are in some ways comparable to the philosophy of the archdeconstructor, Derrida. My skepticism about them and the analytic method based on them is not meant to suggest that I regard Foucault's historical studies as valueless. On the contrary, I recognize that he, together with some other decoders (particularly Barthes), has important things to say. My attack is a form of defense. I wish to uphold the value of traditional forms of interpretation by showing that though Foucault, like other decoders, casts radical doubts upon them in theory, he tends to negate those doubts by the implications of his practice. 21 22Philosophy and Literature M. H. Abrams has defined the traditionalist historian of culture as one who assumes that (a) authors of the past exploited the norms and possibilities of their language to say something determinate, (b) the properly equipped historian can approximate to their meaning, (c) his interpretation can aspire to a reasonable degree of objectivity. ' Let that serve as a working definition of my traditionalist standpoint. This has a philosophical rationale, basically Wittgensteinian and Austinian, which needs to be explained and set over against some of decoding's typical presuppositions. I choose Derrida's as an example. From my perspective, two objections can be leveled against his thought: its tendency to hypostatize the intentional subject as a metaphysical essence which must be reached through and beyond language, and to see language itself as an unrealistically slippery medium. Both objections were raised against him by Searle in their famous polemic with each other.2 Derrida's thought is inscribed within, even while it reacts against, a traditional conception of language as a name-like substitute for essence. According to this conception, influentially represented in this century by Husserl's phenomenology, bits of language somewhat resemble sterling currency bills which bear on their face the legend: "I promise to pay the bearer on demand the sum of? pound(s)" That is, they are potentially capable ofbeing cashed for lumps of being, which can thus be possessed by mind. Derrida counters that the currency is fraudulent: it continually defers presence and possession, rendering problematic its relation to being and self, and their very existence. In order to foster the illusion that he is master of his words, hence of what they designate, Western Man has historically given status of originality to voice rather than to writing, to a form of expression which is seemingly intimate to consciousness rather than external. The paradoxical thesis ofDe lagrammatologie is that writing came first. One of the routes by which Derrida arrives at this conclusion is Saussure's conception of the discontinuous, articulated nature of language and the negative and differential character of linguistic signifiers, not stably linked to universal referents.3 On this basis he builds his idea of différance (a pun on difference and deferral ), the elusive negative margin which makes language possible, and at the same time, makes impossible consciousness's full presence to itself and to being.4 Hence Derrida's notion of language's anarchic and willful power to detach itself from die intentions or usage of its users and to float... (shrink)

It is often thought that presentism is incompatible with time travel. I will argue that this common view is incorrect. Specifically, I will argue that presentism is compatible with some stories that involve closed timelike curves, and that some of these stories are time-travel stories.

Motivated by the search for a Hamiltonian formulation of Einstein equations of gravity which depends in a minimal way on choices of coordinates, nor on a choice of gauge, we develop a multisymplectic formulation on the total space of the principal bundle of orthonormal frames on the 4-dimensional space-time. This leads quite naturally to a new theory which takes place on 10-dimensional manifolds. The fields are pairs of \,\varpi )\), where \\) is a 1-form with coefficients in the Lie (...) algebra of the Poincaré group and \ is an 8-form with coefficients in the dual of this Lie algebra. The dynamical equations derive from a simple variational principle and imply that the 10-dimensional manifold looks locally like the total space of a fiber bundle over a 4-dimensional base manifold. Moreover this base manifold inherits a metric and a connection which are solutions of a system of Einstein–Cartan equations. (shrink)

Proposed models of closed timelike curves have been shown to enable powerful information-processing protocols. We examine the simulation of models of CTCs both by other models of CTCs and by physical systems without access to CTCs. We prove that the recently proposed transition probability CTCs are physically equivalent to postselection CTCs, in the sense that one model can simulate the other with reasonable overhead. As a consequence, their information-processing capabilities are equivalent. We also describe a method for quantum (...) computers to simulate Deutschian CTCs. In cases for which the overhead is reasonable, it might be possible to perform the simulation in a table-top experiment. This approach has the benefit of resolving some ambiguities associated with the equivalent circuit model of Ralph et al. Furthermore, we provide an explicit form for the state of the CTC system such that it is a maximum-entropy state, as prescribed by Deutsch. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Closing the Gaps in Pediatric HIV/AIDS Care, One Step at a TimeLisa V. Adams, Helga Naburi, Goodluck Lyatuu, Paul Palumbo, and C. Fordham von ReynFatuma's* doctors were completely perplexed. It was 2003 and she had returned to the DARDAR clinic in her hometown of Dar es Salaam, Tanzania three times that week with vague complaints of various pains and aches. Her doctors were considering whether these symptoms were due (...) to the initiation of her recent treatment with antiretroviral medications for her HIV infection or related to the last administration of the investigational tuberculosis (TB) vaccine that the DARDAR Health Study was evaluating. Fatuma's doctor, Dr. Lillian Mtei, consulted with Dartmouth's chief of Infectious Disease, Dr. Ford von Reyn, who happened to be in Dar that week on a site visit. Neither physician could determine the basis for her symptoms. Dr. Mtei returned to the exam room once more and this time emerged with the answer: Fatuma had just learned that her three year old daughter was HIV-infected, likely contracted from Fatuma during or shortly after she gave birth to her daughter. Fatuma believed that her HIV diagnosis was a death sentence for her daughter since antiretroviral therapy was not widely available for children.Dr. von Reyn, Dartmouth's lead clinical researcher in Africa and a father, knew too well the harsh reality of inequities in a resource-limited country. He turned to Dr. Mtei and said decidedly, "we need to do something about this."Thus the DARDAR Pediatric Program was born.Pediatric HIV: A Neglected DiseaseThe need for HIV treatment among children in Tanzania, as in most of sub-Saharan Africa, is compelling. At the end of 2009, approximately 160,000 children aged zero to fourteen in Tanzania were living with HIV (Joint United Nations Programme on HIV/AIDS [UNAIDS], 2011). Even with successful roll out of prevention of mother to child transmission programs in Tanzania, there were nearly 29,000 perinatal infections in 2009. As of December 2010, only 18% of these were enrolled in HIV treatment programs (UNAIDS, 2011; World Health Organization [WHO], 2011). Without antiretroviral therapy (ART), one-half of HIV-infected children will die before their second birthday. Since clinical research to determine efficacy and safety of new medical treatments is conducted almost exclusively in adults, provision of new medical treatments to [End Page 75] children always lags behind advances for adults. Furthermore, children are often underrepresented in programs for antiretroviral drugs for the following reasons: 1) they are not prioritized for care; 2) facilities lack infant diagnostic capabilities; 3) there is limited pediatric HIV training and consequently, a shortage of pediatric providers; and 4) pediatric antiretroviral formulations are frequently unavailable. The unacceptable delays in pediatric HIV drug development and treatment access led the international organization Drugs for Neglected Diseases initiative to publish an editorial in which they referred to pediatric HIV as a "neglected disease" (Lallemant, Chang, Cohen, & Pecoul, 2011).The Tip of the Iceberg: More than Just MedicinesWith a grant from the New York-based Foundation for the Treatment of Children with AIDS, the DARDAR Pediatric Program, a joint collaboration between Geisel School of Medicine at Dartmouth and Muhimbili University of Health and Allied Sciences, began seeing patients in May 2006. It was the first dedicated pediatric HIV Care and Treatment Center in Tanzania and operates in accordance with Tanzania's National AIDS Control Programme's guidance. Testing for both children and infants (the latter of which requires a more sophisticated assay) is available.The day the clinic opened we celebrated this collaborative effort that would provide HIV-infected children in Dar es Salaam access to antiretroviral treatment. One of our first patients was a six-year-old boy whose mother, like Fatuma, was a participant in our TB vaccine trial. She had been advised to bring her son to us for HIV screening. Her son looked healthy so she was surprised and understandably distraught when his test results indicated that not only was he HIV-infected, but his CD4 percentage was very low. His mother was reluctant to have him started on antiretrovirals given his general appearance and young age—and that he was... (shrink)

Gödel's Philosophical Legacy Kurt Gödel's contributions to philosophy extend beyond his incompleteness theorems. He engaged deeply with the work of other philosophers, including Immanuel Kant and Edmund Husserl, and explored topics such as the nature of time, the structure of the universe, and the relationship between mathematics and reality. Gödel's philosophical writings, though less well-known than his mathematical work, offer rich insights into his views on the nature of existence, the limits of human knowledge, and the interplay between the (...) finite and the infinite. His work continues to inspire and challenge philosophers, mathematicians, and scientists, inviting them to explore the profound and often enigmatic questions at the heart of human understanding. -/- Kurt Gödel's Broader Contributions to Philosophy Kurt Gödel, while primarily known for his monumental incompleteness theorems, made significant contributions that extended beyond the realm of mathematical logic. His philosophical pursuits deeply engaged with the works of eminent philosophers like Immanuel Kant and Edmund Husserl. Gödel's explorations into the nature of time, the structure of the universe, and the relationship between mathematics and reality reveal a profound and multifaceted intellectual legacy. -/- Engagement with Immanuel Kant Gödel held a deep interest in the philosophy of Immanuel Kant. He admired Kant's critical philosophy, particularly the distinction between the noumenal and phenomenal worlds. Kant posited that human experience is shaped by the mind’s inherent structures, leading to the conclusion that certain aspects of reality (the noumenal world) are fundamentally unknowable. Gödel’s incompleteness theorems echoed this Kantian theme, illustrating the limits of formal systems in capturing the totality of mathematical truth. Gödel believed that mathematical truths exis t independently of human thought, akin to Kant's noumenal realm. This philosophical alignment provided a robust foundation for Gödel's Platonism, which asserted the existence of mathematical objects as real, albeit abstract, entities. -/- Influence of Edmund Husserl Gödel was also profoundly influenced by Edmund Husserl, the founder of phenomenology. Husserl's phenomenology emphasizes the direct investigation and description of phenomena as consciously experienced, without preconceived theories about their causal explanation. Gödel saw Husserl's work as a pathway to bridge the gap between the abstract world of mathematics and concrete human experience. Husserl's ideas about the structures of consciousness and the intentionality of thought resonated with Gödel's views on mathematical intuition. Gödel believed that human minds could access mathematical truths through intuition, a concept that draws on Husserlian phenomenological methods. -/- The Nature of Time and the Universe Gödel's philosophical inquiries extended to the nature of time and the structure of the universe. His collaboration with Albert Einstein at the Institute for Advanced Study led to the development of the "Gödel metric" in 1949. This solution to Einstein's field equations of general relativity described a rotating universe where time travel to the past was theoretically possible. Gödel's model challenged conventional notions of time and causality, suggesting that the universe might have a more intricate structure than previously thought. Gödel's exploration of time was not just a mathematical curiosity but a profound philosophical statement about the nature of reality. He questioned whether time was an objective feature of the universe or a construct of human consciousness. His work hinted at a timeless realm of mathematical truths, aligning with his Platonist view. -/- Mathematics and Reality Gödel's philosophical outlook extended to the broader relationship between mathematics and reality. He believed that mathematics provided a more profound insight into the nature of reality than empirical science. For Gödel, mathematical truths were timeless and unchangeable, existing independently of human cognition. This perspective led Gödel to critique the materialist and mechanistic views that dominated 20th-century science and philosophy. He argued that a purely physicalist interpretation of the universe failed to account for the existence of abstract mathematical objects and the human capacity to understand them. Gödel's philosophy suggested a more integrated view of reality, where both physical and abstract realms coexist and inform each other. -/- Gödel's Exploration of Time Kurt Gödel, one of the most profound logicians of the 20th century, ventured beyond the confines of mathematical logic to explore the nature of time. His inquiries into the concept of time were not merely theoretical musings but were grounded in rigorous mathematical formulations. Gödel's exploration of time challenged conventional views and opened new avenues of thought in both physics and philosophy. -/- Gödel and Einstein Gödel’s interest in the nature of time was significantly influenced by his friendship with Albert Einstein. Both were faculty members at the Institute for Advanced Study in Princeton, where they engaged in deep discussions about the nature of reality, time, and space. Gödel's exploration of time culminated in his solution to Einstein's field equations of general relativity, known as the Gödel metric. -/- The Gödel Metric In 1949, Gödel presented a model of a rotating universe, which became known as the Gödel metric. This solution to the equations of general relativity depicted a universe where time travel to the past was theoretically possible. Gödel’s rotating universe contained closed timelike curves (CTCs), paths in spacetime that loop back on themselves, allowing for the possibility of traveling back in time. The Gödel metric posed a significant philosophical challenge to the conventional understanding of time. If time travel were possible, it would imply that time is not linear and absolute, as commonly perceived, but rather malleable and subject to the geometry of spacetime. This raised profound questions about causality, the nature of temporal succession, and the very structure of reality. -/- Philosophical Implications Gödel’s exploration of time extended beyond the mathematical implications to broader philosophical inquiries: Nature of Time: Gödel questioned whether time was an objective feature of the universe or a construct of human consciousness. His work suggested that our understanding of time as a linear progression from past to present to future might be an illusion, shaped by the limitations of human perception. -/- Causality and Free Will: The existence of closed timelike curves in Gödel’s model raised questions about causality and free will. If one could travel back in time, it would imply that future events could influence the past, potentially leading to paradoxes and challenging the notion of a deterministic universe. -/- Temporal Ontology: Gödel's work contributed to debates in temporal ontology, particularly the debate between presentism (the view that only the present exists) and eternalism (the view that past, present, and future all equally exist). Gödel’s rotating universe model seemed to support eternalism, suggesting a block universe where all points in time are equally real. Philosophy of Science: Gödel’s exploration of time had implications for the philosophy of science, particularly in the context of understanding the limits of scientific theories. His work underscored the importance of considering philosophical questions when developing scientific theories, as they shape our fundamental understanding of concepts like time and space. -/- Legacy Gödel’s exploration of time remains a significant and controversial contribution to both physics and philosophy. His work challenged established notions and encouraged deeper inquiries into the nature of reality. Gödel’s rotating universe model continues to be a topic of interest in theoretical physics and cosmology, inspiring new research into the nature of time and the possibility of time travel. In philosophy, Gödel’s inquiries into time have prompted ongoing debates about the nature of temporal reality, the relationship between mathematics and physical phenomena, and the limits of human understanding. His work exemplifies the intersection of mathematical rigor and philosophical inquiry, demonstrating the profound insights that can emerge from such an interdisciplinary approach. The Temporal Ontology of Kurt Gödel Kurt Gödel's profound contributions to mathematics and logic extend into the realm of temporal ontology—the philosophical study of the nature of time and its properties. Gödel's insights challenge conventional perceptions of time and suggest a more intricate, layered understanding of temporal reality. This essay explores Gödel's contributions to temporal ontology, particularly through his engagement with relativity and his philosophical reflections. -/- Gödel's Rotating Universe One of Gödel’s most notable contributions to temporal ontology comes from his work in cosmology, specifically his solution to Einstein’s field equations of general relativity, known as the Gödel metric. Introduced in 1949, the Gödel metric describes a rotating universe with closed timelike curves (CTCs). These curves imply that, in such a universe, time travel to the past is theoretically possible, presenting a significant challenge to conventional views of linear, unidirectional time. -/- Implica tions for Temporal Ontology Gödel's rotating universe model has profound implications for our understanding of time: Eternalism vs. Presentism: Gödel’s model supports the philosophical stance known as eternalism, which posits that past, present, and future events are equally real. In contrast to presentism, which holds that only the present moment exists, eternalism suggests a "block universe" where time is another dimension like space. Gödel’s rotating universe, with its CTCs, reinforces this view by demonstrating that all points in time could, in principle, be interconnected in a consistent manner. Non-linearity of Time: The possibility of closed timelike curves challenges the idea of time as a linear sequence of events. In Gödel’s universe, time is not merely a straight path from past to future but can loop back on itself, allowing for complex interactions between different temporal moments. This non-linearity has implications for our understanding of causality and the nature of temporal succession. Objective vs. Subjective Time: Gödel’s work invites reflection on the distinction between objective time (the time that exists independently of human perception) and subjective time (the time as experienced by individuals). His model suggests that our subjective experience of a linear flow of time may not correspond to the objective structure of the universe. This raises questions about the relationship between human consciousness and the underlying temporal reality. -/- Gödel and Philosophical Reflections on Time Gödel’s engagement with temporal ontology was not limited to his cosmological work. He also reflected deeply on philosophical questions about the nature of time and reality, drawing on the ideas of other philosophers and integrating them into his own thinking. Kantian Influences: Gödel was influenced by Immanuel Kant’s distinction between the noumenal world (things as they are in themselves) and the phenomenal world (things as they appear to human observers). Gödel’s views on time echoed this distinction, suggesting that our perception of time might be a phenomenon shaped by the limitations of human cognition, while the true nature of time (the noumenal aspect) might be far more complex and non-linear. Husserlian Phenomenology: Gödel’s interest in Edmund Husserl’s phenomenology also informed his views on time. Husserl’s emphasis on the structures of consciousness and the intentionality of thought resonated with Gödel’s belief in the importance of intuition in accessing mathematical truths. Gödel’s reflections on time incorporated a phenomenological perspective, considering how temporal experience is structured by human consciousness. Mathematical Platonism: Gödel’s Platonist views extended to his understanding of time. Just as he believed in the independent existence of mathematical objects, Gödel saw time as an objective entity with a structure that transcends human perception. His work on the Gödel metric can be seen as an attempt to uncover this objective structure, revealing the deeper realities that underlie our experience of time. (shrink)

There has been considerable recent interest in the consequences of closed timelike curves (CTCs) for the dynamics of quantum mechanical systems. A vast majority of research into this area makes use of the dynamical equations developed by Deutsch, which were developed from a consistency condition that assumes that mixed quantum states uniquely describe the physical state of a system. We criticize this choice of consistency condition from an epistemic perspective, i.e., a perspective in which the quantum state represents (...) a state of knowledge about a system. We demonstrate that directly applying Deutsch’s condition when mixed states are treated as representing an observer’s knowledge of a system can conceal time travel paradoxes from the observer, rather than resolving them. To shed further light on the appropriate dynamics for quantum systems traversing CTCs, we make use of a toy epistemic theory with a strictly classical ontology due to Spekkens and show that, in contrast to the results of Deutsch, many of the traditional paradoxical effects of time travel are present. (shrink)

We introduce the Causal Compatibility Conjecture for the Events, Trees, Histories approach to Quantum Theory in the semi-classical setting. We then prove that under the assumptions of the conjecture, points on closed causal curves are physically indistinguishable in the context of the ETH approach to QT and thus the conjecture implies a compatibility of the causal structures even in presence of closed causal curves. As a consequence of this result there is no observation that could be (...) made by an observer to tell any two points on a closed causal curve apart. We thus conclude that closed causal curves have no physical significance in the context of the ETH approach to QT. This is an indication that time travel will not be possible in a full quantum theory of gravity and thus forever remain a fantasy. (shrink)

Background Individual physicians and physician-associated factors may influence patients’/surrogates’ autonomous decision-making, thus influencing the practice of do-not-resuscitate orders. The objective of this study was to examine the influence of individual attending physicians on signing a DNR order. Methods This study was conducted in closed model, surgical intensive care units in a university-affiliated teaching hospital located in Northern Taiwan. The medical records of patients, admitted to the surgical intensive care units for the first time between June 1, 2011 and (...) December 31, 2013 were reviewed and data collected. We used Kaplan–Meier survival curves with log-rank test and multivariate Cox proportional hazards models to compare the time from surgical intensive care unit admission to do-not-resuscitate orders written for patients for each individual physician. The outcome variable was the time from surgical ICU admission to signing a DNR order. Results We found that each individual attending physician’s likelihood of signing do-not-resuscitate orders for their patients was significantly different from each other. Some attending physicians were more likely to write do-not-resuscitate orders for their patients, and other attending physicians were less likely to do so. Conclusion Our study reported that individual attending physicians had influence on patients’/surrogates’ do-not-resuscitate decision-making. Future studies may be focused on examining the reasons associated with the difference of each individual physician in the likelihood of signing a do-not-resuscitate order. (shrink)

continent. 1.4 (2011): 286—310. This mad play of writing —Stéphane Mallarmé Somewhere in between mathematics and theory, light and dark, physicality and projection, oscillates the poetry of Alessandro De Francesco. The texts hold no periods or commas, not even a capital letter for reference. Each piece stands as an individual construction, and yet the poetry flows in and out of the frame. Images resurface from one poem to the next, haunting the reader with reincarnations of an object lost in the (...) grass or a representation of a pear in a Dutch still life, embedded in cycles of cinematic close ups and multiple dimensions. As a whole, De Francesco’s oeuvre suggests, to use the title of one of his works, a redefinition —linguistic, epistemological, personal. The poem The End (un’agenda) (The End (an agenda)) opens with a quote by literary theorist Maurice Blanchot, which may be translated as follows: Speaking is not seeing. Speaking frees thought from this optical imperative that in the Western tradition, for thousands of years, has subjugated out approach to things, and induced us to think under the guaranty of light or under the threat of its absence.[1] In writing, De Francesco seeks to redefine our approach to things. His poems, like Blanchot’s writings, speak to both illuminate and to obscure. The reader hangs in an absence of reality within language that necessitates an attempt at interpretation, yet renders such a search ultimately futile. De Francesco draws the anonymous images that appear in this poem from the city of Paris, his current home. The fragmented narrative depicts an inner doubt of realness, calling for a confirmation of a physical existence beyond verbalization and cogitation. Cyclical references to film throw into question the reliability of the reality he creates. The light, sometimes red and safe, other times absent and murky, cannot necessarily be trusted as a guaranteed means of illumination. Blanchot’s distinction between language and visualization, and the relationship of each to reality, though linked specifically to The End (un’agenda) , can be a lens through which to read any of the three works that follow. assente obliqua (absent oblique) is composed of descriptions of six still life paintings, ranging from Dutch masterpieces of the seventeenth century to 1960s minimalism. The actual images of the paintings are absent, and the text is the sole source and object of a virtual reality created around the artwork. “Absent oblique” refers to the light source placed outside of the frame, which both informs and distracts viewing of the scene. Although mere description can be unreliable and unsatisfying in its necessary limitation, the representational act of description is shown as more than just a human want. It is a need, a means by which to grapple with an unsure reality. As the illustrations progress, they descend into abstraction and chaos. The precariously placed plate triggers the movement: the bottle bursts and the objects collapse into the movement of a tracking film camera. corpo estraneo in moto ascensionale (foreign body in ascending motion) is prose poetry in action. Its objective tone of description is skewed by the subjectivity of the narrative as horrific images are relayed in fragmented but matter-of-fact manner. A “foreign body” is both a mass of cancerous cells, and a corporeal description, and the poem takes the reader on a journey back and forth between the two, destination unclear. Beyond a questioning of the real, corpo estraneo in moto ascensionale is an examination of the possible. De Francesco’s poetry becomes a camera obscura through which to observe the constant flux of light and dark that blurs our reality. His work is colored by the idea of apo koinou , a Greek term meaning “from the common” that involves a construction of two clauses with a shared word or phrase. Through such melting of meaning, De Francesco creates a fluid ambiguity that is nonetheless grounded in bodily concepts. In assente obliqua , the reader is confronted with a description of a still life that rapidly transforms into a more chilling scene: the membrane of the mushroom in the basket emerges behind the white cloth a body could hide itself that asks for help In the realm of pure description, there is a mushroom that peeks out from behind a white cloth in a basket. Behind the white cloth, too, there could be a body, hiding, asking for help. Such an elision elicits disorienting mistrust in temporality, but also expands the planar possibilities of syntactical meaning. A white cloth is not merely a construct in still life painting, but veil that both shields and reveals potential mysteries. It is a proposed alternative to a traditional Western binary of subjectivity and objectivity. The apo koinou construction is rare in modern English, having slipped out of use after its resurgence in Old English poetry. De Francesco reintroduces this blur of object and subject relations into a modern light. He draws inspiration from a device used by Gruppo 63 founder and avant-garde poet Antonio Porta tended toward repetition of phrases in third person perspective. In Italian, it is perfectly grammatically correct to omit the subject, including only a verb conjugation. Gender, even humanity unknown, the subject dissolves into the action, thus giving to the poetry the power to change the reader’s perception of who or what is actually acting. To further push the relative boundaries of experience, De Francesco expands his written poetry into what he calls “reading environments.” In these sound experiments, De Francesco’s voice reading his poetry is manipulated by real time digital voice processing. The written is transformed to the spoken, and then injected with currents of electric sound. “At each activation of word in the darkness,” (from The End (un’agenda) ) language is permutated into a nonphysical yet all-encompassing being. In these projects, realized all over Europe, De Francesco continues his examination of the word’s potency beyond the page and into an “n-dimensional space,” where the lines between nature and affect are intertwined. To publish excerpts of De Francesco’s oeuvre is to show screen shots of full-length film, to read pull quotes from a philosophy treatise. In these poems, there are questions, not to be answered, but to be questioned again. The words will oscillate in and out of the square construction found in his poems, out of the borders of the page, out of the rectangle of the laptop screen. NOTES (1) Blanchot, Maurice. The Infinite Conversation . Trans. Susan Hanson. Minneapolis: University of Minnesota Press, 1993. 27. EDITORS' NOTE The .pdf above contains about twenty pages of translation and the original Italian poetry. Below we provide only a brief account. The End (an agenda) Parler, ce n’est pas voir. Parler libère la pensée de cette exigence optique qui, dans la tradition occidentale, soumet depuis des millénaires notre approche des choses et nous invite à penser sous la garantie de la lumière ou sous la menace de l’absence de lumière. —Maurice Blanchot in this n-dimensional space i could spy on myself from the cracks while going back and forth from the summer to the wardrobe from the night to the parking lot but something filters in through the half-closed shutters becomes an event enunciation we stay without explanation like parallel curves on the back of a solid growing older she enters the garden always repeats certain phrases the elevator to be redone the neighbor’s music the steps the pavement furls like the leaves of a fern when touched she is framed from behind while she moves rocking she covers distances slowly a bag overflows from the wardrobe something stirs inside but then the suitcase comes open not even by my hand it’s the objects that are starting to filter out the little red haired monster watches idling the appointments written on one of your agendas two years old still seem urgent each letter holds itself upright on the page with flourishes and arabesques each angle has its own geography i’m trying to describe the path the fingers trace on the carpet the zipper takes the opposite route we are suspended on the stairs above the water in the center is the summer seen from above the darkness of the city passes from one headlight to the next the surfaces of our arms cohere and are shiny underneath the blinking of a sign each pore is an open expanse the body dreams the hair gives form to the possible some daring swimmers were throwing themselves into the seine they swam upstream up to the first quay look there could exist behind the screen a room where even when the lamp is out and the curtains drawn even when the suitcase wasn’t closed everything seemed red everything calm construction of a four-dimensional tetrahedron by R. Courant – H. Robbins, What is Mathematics? Oxford University Press, 1941  . (shrink)

In lieu of an abstract, here is a brief excerpt of the content:The Journal of Aesthetic Education 38.2 (2004) 80-87 [Access article in PDF] The Beauty of Henri Matisse David Carrier Because beauty has for a long time now been politically incorrect (at least among certain influential critics and academic historians) the art of Henri Matisse has recently suffered from a kind of benign neglect. His goals were luxury, calm, and voluptuousness, not social critique. He painted female nudes, and (...) was preoccupied with artistic tradition. Celebrated in his own lifetime, he died a rich man. Matisse's famous identification of the work of art with a good armchair is another provocation. His paintings, after all, are very expensive armchairs. Liberated from any vital connection with everyday life, they often seem merely escapist. In her recent book, On Beauty and Being Just, Elaine Scarry remarks, "Matisse never hoped to save lives. But he repeatedly said that he wanted to make paintings so serenely beautiful that when one came upon them, suddenly all problems would subside."1 That some of Matisse's paintings succeed in being serenely beautiful seems self-evident to Scarry, to me, and to a great many other art lovers. What is perhaps worth exploring at greater length, however, is precisely how Matisse's paintings succeed in achieving their unfashionable goal. What is it that makes the work of Matisse so serenely beautiful?To start, consider The Painter and His Model (1918-1921), made just after his move from Paris to Nice. Like other works from this period of his career, this picture raises special problems, even for many commentators who admire his earlier experimentation. At the left, we see the painter working on a canvas of a nude. "Expression, for me," Matisse wrote, "does not reside in passions glowing in a human face."2 Like most of his models, this one appears expressionless. She poses at the center of the picture, beneath a window that admits the light filling the room. A flowering palm, a symbol of fertility, is the only object visible from the world outside the studio.Leaving behind his family and the luxury of his Paris home, Matisse lived and worked in a small room like this one. The entire picture is filled [End Page 80] with patterns — a red tablecloth on the left, orange wallpaper on the right, blue stripes on the painter's shirt, a red grid on the floor. A dark painting hangs above flowers on the table. The Painter and His Model shows the artist hard at work, but the composition appears effortlessly spontaneous. Matisse, who lived only to paint during his time in Nice, concealed the endless effort required to make his beautiful pictures. A man from North France, he discovered the power of light. There is nothing special about this room, but under the spell of his model Matisse makes it appear ravishing. Intense Mediterranean sunlight transforms ordinary patterns into a world of visual luxury.We know that The Painter and His Model is beautiful because we get great pleasure seeing the model in the golden room. Her skin is close in tone to, or in harmony with the colors of the walls; her curves harmonize with the two vases, and play against the spreading linear grids. As we move our eyes easily from the model to the entire picture, we experience a kind of sublimated erotic pleasure. In "Notes of a Painter," Matisse gave an apt description of his approach in The Painter and His Model. Suppose I want to paint a woman's body: first of all I imbue it with grace and charm, but I know that I must give something more. I will condense the meaning of this body by seeking its essential lines. The charm will be less apparent at first glance, but it must eventually emerge from the new image which will have a broader meaning, one more fully human. (MA, 36) He does not use the word "beauty," but speaks instead about expression and harmony. When he published this manifesto, Matisse was painting very different sorts of pictures — portraits, scenes of nudes in utopian settings, and... (shrink)

It is claimed that unacceptable constraints on initial data are imposed by certain responses to paradoxes that threaten time travel, closed timelike curves (CTCs) and other backwards causation hypotheses. In this paper I argue against the following claims: to say “contradictions are impossible so something must prevent the paradox” commits in general to constraints on initial data, that for fixed point dynamics so-called grey state solutions explain why contradictions do not arise, and the latter have been proved (...) to avoid constraints on initial data. †To contact the author, please write to: Philosophy, University of Queensland, Brisbane, Queensland 4072, Australia; e-mail: [email protected]. (shrink)

We present a formal derivation of the Mino–Sasaki–Tanaka–Quinn–Wald (MSTQW) equation describing the self-force on a (semi-) classical relativistic point mass moving under the influence of quantized linear metric perturbations on a curved background space–time. The curvature of the space–time implies that the dynamics of the particle and the field is history-dependent and as such requires a non-equilibrium formalism to ensure the consistent evolution of both particle and field, viz., the worldline influence functional and the closed- time-path (...) (CTP) coarse-grained effective action. In the spirit of effective field theory, we regularize the formally divergent self-force by smearing the local part of the retarded Green’s function and employing a quasi-local expansion. We derive the MSTQW–Langevin equations describing the perturbations of the particle’s worldline about its semi-classical trajectory resulting from interactions with the quantum fluctuations of the linear metric perturbations. Finally, we demonstrate that the quantum fluctuations of the field could, in principle, leave imprints on gravitational waveforms expected to be observed by gravitational interferometers, thereby encoding information about tree-level perturbative quantum gravity. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Figuring Myself Out:Certainty, Injury, and the Poststructuralist Repositioning of Bodies of IdentityJames Haywood Rolling Jr. (bio)CertaintyI have been attempting to figure myself out. Out of chaos and incompletion, toward increased certainty. I have been at this task of construction for quite some time now. I have just proposed my dissertation and my intentions are once again uncertain. My dissertation is to be a self-study. It is also a (...) story about uncertainty and my attempts to redeem a clear definition, to be named a peer and a colleague among artists, writers, and teachers. I have been uncertain as a little boy; uncertain as a son; uncertain as a student of architecture; uncertain as an artist and writer; uncertain as a teacher; uncertain as a black man. To compensate, I have sought the conferral of certainty, a name among leaders in many fields of inquiry. Still, it is not easy to forget that certainty has also been the cause of great injury to my body, to my mind.On sunny afternoons after school all the kids came outside to play. The air would fill with echoes going back and forth between the red brick and stone buildings on both sides of our narrow street. Pounding rubber balls, the taps and scratches of shoe heels, and the slapping of sneakers on the cement and asphalt.Sometimes white chalk would appear and hopscotch boxes were quickly drawn on the neat squares of cement pavement in front of my Grandma's house. Grandma lived next door to us. Houses on our block were side by side, sharing each other's walls.On a particular day, similar to other days, I watched as a small flat stone was tossed to bounce across the cement into a numbered box. I watched the one foot, two feet, one foot hops from box to box to stop and balance on one small hopping foot, steadying itself, to drop a hand to pick up the stone. Some little girl came to sit beside me and asked me to look at her. We were sitting on one of Grandma's two wooden benches, just inside the front gate. [End Page 46] Two steps down was the sidewalk and other kids. I ignored the girl. I made sure my body had no contact with hers on the bench. Why was she talking to me anyway? Didn't she see I didn't have anything I wanted to say?"Look at me!" she said, tugging at my arm."Will you stop it!" I snapped back, jerking my arm away. Being touched was not natural to me. My family didn't touch. I tightened the skin of my eyebrows and the bridge of my nose into a frown."Smile!" the little girl said slyly, trying to tickle me."Leave me alone!" I yelled. I tried to move away from the touching.I must have grinned. Grinning relaxes the frowns on faces. The girl clapped a hand over her mouth, all giggles. I asked what she was laughing so loud for. The kids out in front of us now had our attention. I felt like I was now being watched. I can't remember the faces, just the noise and voices that seemed to stop. The little girl stood up, pointed at my face and declared, finger in my face, pointing, speaking out loud, "Look! He only has one dimple! See?! Look at his face!""No I don't," I said, dropping my face, my eyes, my voice. My head was down and I didn't want to see if anyone was looking. The attention made my face warm and I needed to move away fast. "No I don't," I repeated, stiffly. My whole head seemed to glow brightly, very hot, drawing lots of attention. I was beneath windows, very near, on both sides of the street, always with onlookers. I rushed through the painted iron gate, going quickly next door, upstairs to "our house," to the second floor apartment we lived in, down the hallway so dark after the bright outside, around a curve and a corner, into the bathroom, closing the door behind me. Locking the door... (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Unsaying Life Stories:The Self-Representational Art of Shirin Neshat and GhazelAphrodite Désirée Navab (bio)What connects the two artists in Figures 1 and 2 across time and place? (See pages 40 and 41.) The protagonists seem to be so "at home" in their landscape that they do not stand out as disruptions to a cultural rhythm. They are wearing clothing that symbolizes Iran, and they are in an environment that (...) evokes Iranian art and architecture. In Figure 1, a scene in Shirin Neshat's video Soliloquy (1999), a woman stands near the kind of dome one often sees in Islamic architecture; the compatibility of the curved and the straight lines is striking. The woman is washing herself, possibly in preparation for prayer. Her hands are artistically dyed with henna. Her eyes are closed as the water runs down her face. She seems to be unaware of the camera, involved in a private moment, a purification ritual perhaps. Her clothing, her hands, and the architectural background are all consistent with familiar images of the Middle East. The woman marching in a black chador in a video still by Ghazel (Figure 2) also seems to be quite "at home." The text underneath the image says that both her grandfathers were colonels. This "bothness" is repeated by the text written underneath the image, which appears both in English and in French. She marches to the right of the frame with the straight posture and hint of pants and boots characteristic of a soldier. Like the protagonist in Neshat's video, she neither looks at the camera nor seems to care that it is there. She seems to be re-enacting a private moment of family history.At least, this is what the images say at first glance. Upon closer inspection, the viewer learns that the two protagonists are the artists themselves. They are more than conscious of the camera; they have actually directed these visual narratives. They are posing. This is one role from among many that they could have played. Both artists are native to Iran, but they are [End Page 39] acting in their own productions. They are playing a particular role. They have made the directorial decisions about camera angle and distance, about the time and place, and about the final look of the production. They make images: they are fully aware that they have pictured themselves alongside symbols of Iran. Click for larger view View full resolutionFigure 1.Shirin Neshat. Soliloquy, 1999, production still.So why are they pretending not to be conscious of the camera? The conscious decisions of the artists point to an issue that is left unsaid but whose absence says a lot. Perhaps, beneath all this effort to seem comfortable, there is discomfort as well. Are these people in fact "at home," or has home become foreign to them? Has this alienation propelled these artists to picture themselves together with readily identifiable, traditional markers of Iranian culture? Are these productions a way of re-negotiating their place with their native land, to find a voice, a space from which to speak?Culturally hybrid persons are often caught in the crossfire of prejudices. For hybrid Iranians, these prejudices are exacerbated by international political tensions that fall along three dimensions of limited visions. They include historical prejudice, where each nation dominates the other in the telling of history; cultural prejudice, stemming from mutual suspicion and ignorance; and political prejudice, as a result of inflexibility, of an unwillingness to [End Page 40] envision the other's view. Art can be a powerful means for challenging the stereotypes of mutually antagonistic nations. In autobiographical art, moreover, artists may use the "telling-self" to "unsay" what has been attributed to them through these stereotypes. By literally and metaphorically engaging the public in seeing alternative realities and histories, these artist-philosophers offer an alternative of historical collaboration, cultural knowledge, and political flexibility. Click for larger view View full resolutionFigure 2.Ghazel, Me series, 1997–2000, video still.This deconstructive approach to representation is a significant feature of the camera-based work of two contemporary Iranian women artists: Shirin Neshat (b. 1957) and Ghazel (b. 1966... (shrink)

In lieu of an abstract, here is a brief excerpt of the content:On Dante, Hyperspheres, and the Curvature of the Medieval CosmosWilliam EggintonIn the course of his lectures on medieval literature at Oxford University in the 1950s C. S. Lewis would ask students to walk alone at night, gaze at the star-filled sky, and try to imagine how it might look to a walker in the Middle Ages. It would not likely have occurred to him that some forty years later (...) several astrophysicists would ask that their readers perform the same activity, at least figuratively—not, however, with the intention of experiencing medieval conceptions of the cosmos but rather in order to begin to imagine the shape of our own. One of the astrophysicists in question is Stanford Professor Emeritus Robert Osserman, whose 1995 book The Poetry of the Universe is an attempt to acquaint lay readers with what the most recent research suggests is the shape of the universe by leading them through a brief history of the mathematical and technological developments that made such boundary-breaking thought possible. Paradoxically, when it comes to trying to imagine that all-encompassing form which is derived from a four-dimensional mathematical model called a hypersphere, he turns not to ultra-modern computer-generated images nor to dry but technically accurate exegeses of mathematical formulae but rather to the verses of a fourteenth-century Italian poet, Dante Alighieri. His claim is that in the third canticle of the Divine Comedy, which details his ascent through the heavens, Dante describes the cosmos with astonishing precision as a hypersphere, exactly as modern physics has determined it to be.If the cosmology of the present makes use of Dante heuristically, however, it never asks the most obvious question: Why? Why does one need to go back to the fourteenth century for a poetic description of how the universe appears to modern science? Osserman assumes it to be a mere coincidence, and why should he not? What possible access would a thinker—a poet even—of the European Middle Ages have to the highest achievements of almost six centuries of subsequent thought? In answering this question, I am not proposing to naively interpret the past in our own image, claiming Dante to be a mathematical genius [End Page 195] before his time. I am, however, suggesting that there is an excellent explanation for why one must look to the fourteenth century for models of expression adequate to the challenges posed by nineteenth and twentieth-century advances in mathematics: namely, that in the course of the Scientific Revolution, wherein were laid the epistemological foundations for the discoveries of modern science, certain possibilities of thought and imagination were discarded, forgotten, and certain abilities were, if only temporarily, lost. The Middle Ages has long been painted as a period whose culture was hostile to free thought and new knowledge; perhaps it is now time to recognize that it was also a time in which phenomena could sustain mutually exclusive and contradictory explanations, when the battle between faith and science had not yet been conclusively won by either side, and when the efforts to bridge the stories they told could produce conceptual edifices whose mere possibility would be unthinkable only 200 years later. This essay is about one such conceptual edifice and how openness to its perspective allowed a poet to put into words what could not be imagined by his descendants, and what eludes us even today.The Shape of the Modern UniverseImagine that you are a completely flat creature, living happily in your two-dimensional world.1 As observers we are outside this world, and we can see you milling about with your flat friends, blissfully unaware of the uncharted regions one dimension away on either side of you. Now imagine that this plane is not flat—in the sense of rectilineal—as you might have created it in your mind, but rather is curved; in fact it is a sphere. Assuming that this sphere is large enough, there is no reason that you, an inhabitant of this surface, should be aware of its curvature. Even we, the three-dimensional observers, if close enough to the surface, would not recognize its curvature. One could conjecture, however... (shrink)

It has been suggested by several philosophers that many of the so-called paradoxes of backward time travel can be resolved if we conceive of the backward time traveller as having a zig-zag or N-shaped world line in spacetime. In this I am in general agreement. But there is still a problem in conceiving of backward time travel this way. In this note I will show how we can solve this problem by conceiving of backward time travel (...) in terms of the closed time-like world lines in certain general relativistic space-times. Indeed, it has often been claimed that such world models as Godei spacetime show that backward time travel is conceivable. Our discussion will help to make clear just why this claim is correct. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:The Journal of Aesthetic Education 38.2 (2004) 80-87 [Access article in PDF] The Beauty of Henri Matisse David Carrier Because beauty has for a long time now been politically incorrect (at least among certain influential critics and academic historians) the art of Henri Matisse has recently suffered from a kind of benign neglect. His goals were luxury, calm, and voluptuousness, not social critique. He painted female nudes, and (...) was preoccupied with artistic tradition. Celebrated in his own lifetime, he died a rich man. Matisse's famous identification of the work of art with a good armchair is another provocation. His paintings, after all, are very expensive armchairs. Liberated from any vital connection with everyday life, they often seem merely escapist. In her recent book, On Beauty and Being Just, Elaine Scarry remarks, "Matisse never hoped to save lives. But he repeatedly said that he wanted to make paintings so serenely beautiful that when one came upon them, suddenly all problems would subside."1 That some of Matisse's paintings succeed in being serenely beautiful seems self-evident to Scarry, to me, and to a great many other art lovers. What is perhaps worth exploring at greater length, however, is precisely how Matisse's paintings succeed in achieving their unfashionable goal. What is it that makes the work of Matisse so serenely beautiful?To start, consider The Painter and His Model (1918-1921), made just after his move from Paris to Nice. Like other works from this period of his career, this picture raises special problems, even for many commentators who admire his earlier experimentation. At the left, we see the painter working on a canvas of a nude. "Expression, for me," Matisse wrote, "does not reside in passions glowing in a human face."2 Like most of his models, this one appears expressionless. She poses at the center of the picture, beneath a window that admits the light filling the room. A flowering palm, a symbol of fertility, is the only object visible from the world outside the studio.Leaving behind his family and the luxury of his Paris home, Matisse lived and worked in a small room like this one. The entire picture is filled [End Page 80] with patterns — a red tablecloth on the left, orange wallpaper on the right, blue stripes on the painter's shirt, a red grid on the floor. A dark painting hangs above flowers on the table. The Painter and His Model shows the artist hard at work, but the composition appears effortlessly spontaneous. Matisse, who lived only to paint during his time in Nice, concealed the endless effort required to make his beautiful pictures. A man from North France, he discovered the power of light. There is nothing special about this room, but under the spell of his model Matisse makes it appear ravishing. Intense Mediterranean sunlight transforms ordinary patterns into a world of visual luxury.We know that The Painter and His Model is beautiful because we get great pleasure seeing the model in the golden room. Her skin is close in tone to, or in harmony with the colors of the walls; her curves harmonize with the two vases, and play against the spreading linear grids. As we move our eyes easily from the model to the entire picture, we experience a kind of sublimated erotic pleasure. In "Notes of a Painter," Matisse gave an apt description of his approach in The Painter and His Model. Suppose I want to paint a woman's body: first of all I imbue it with grace and charm, but I know that I must give something more. I will condense the meaning of this body by seeking its essential lines. The charm will be less apparent at first glance, but it must eventually emerge from the new image which will have a broader meaning, one more fully human. (MA, 36) He does not use the word "beauty," but speaks instead about expression and harmony. When he published this manifesto, Matisse was painting very different sorts of pictures — portraits, scenes of nudes in utopian settings, and... (shrink)

“Artworks are not being but a process of becoming” —Theodor W. Adorno, Aesthetic Theory In the everyday use of the concept, saying that something is grotesque rarely implies anything other than saying that something is a bit outside of the normal structure of language or meaning – that something is a peculiarity. But in its historical use the concept has often had more far reaching connotations. In different phases of history the grotesque has manifested its forms as a means of (...) subversive resistance against society’s prevailing notions of form and power. What aids this impact and distinguishes two of its basic stylistic features is the grotesque’s dissolution of form and its hyperbole. Such grotesqueries, however, soon solidify into new forms, new structures of meaning, hierarchy and practice, and in this sense the history of the grotesque is, on one hand, a continual opposition and transgression of the prevailing notions of art as well as of God and humanity, while on the other hand it offers continual resistance to its own solidifying process. As such the grotesque will not and cannot be contained in form without it losing the very thing that makes it grotesque. Even though it is somewhat easy to point out certain stylistic features of the grotesque, the sum of those features tell us very little about what is at play within it. Definitions concerned with the grotesque’s content rather than its form faces similar difficulties. Throughout history, expressions relating to the grotesque have been used in defense of a whole host of different social and cultural discourse including, for instance, Catholicism (See Erhard Schön’s Der Teufel mit der Sackpfeife , 1536), Protestantism (See Lucas Cranach’s Der Papstesel , 1523), a material folk culture (see Mikhail Bakhtin’s Rabelais and his World , 1984) and an idealistic romantic structure of meaning (see Wolfgang Kayser’s The Grotesque in Art and Literature , 1957). Thus though the grotesque cannot be reduced to the expression of certain forms or meanings, in order to examine what the grotesque is about one has to try to see how it’s relationship to flow and process and how, by maintaining this relationship, it attempts to avoid solidifying into form and meaning. The process of the grotesque alluded to here revolves around a play between periphery and center, the marginalized and the dominant. Most often this is expressed as a direct negation of the center of power. In the medieval grotesque tradition of the carnival, for example, it is expressed by its emphasis on the nether regions of the body as the center of creation of meaning. Spirit does not come from above, but from the belly, buttocks and genitals, and there is, expressed in this manner, a mockery of the predominant Christian notion of truth and meaning. Such inversions of the sites of meaning most often explicitly express an increased interest in materiality instead of ideal content which comes to the fore through the play between periphery and center. Even in early grotesque Renaissance art (for example in the works of Raphael) the depiction of the mythological or ideal reveals an exploration of the possibilities of the material. The works of art thus explore their own boundaries rather than act as vessels of the divine and in this way the grotesque explores the limits of form and materiality. This in turn brings to the fore a metaphysical dimension in the workings of the grotesque: It is an immanent exploration of its own boundaries. Materiality and metaphysics are joined together, because it is through the awareness of itself as a structuring (dis)order that it places itself in opposition to the prevailing notions of form and power. This way the grotesque expresses an awareness of the division of sign and reality and a search for this reality. It implicitly expresses the awareness that meaning is not something God-given and static, but fluctuating and man-made. In modern explorations of the history of the grotesque it is commonly seen as a form of realism that manifests a shift from the ideal towards the material, freeing art from representing some hidden higher order and instead making the work of art the very site of creation and meaning. Going even further, the grotesque actively opposes the notions of the ideal by marking a shift from an ahistorical view of the world towards the historical. However, this also makes clear why the grotesque has a tendency to solidify into new static forms of meaning, for by establishing itself as a subversive counterforce there is an idea of transgression and emancipation. That is why the grotesque often historicizes and relativizes only to repeat the mistakes of that which it negates: putting itself in the king’s chair. The exploration of the material seems to create new forms and notions of the ideal. The representation of an otherness outside the prevailing notions of meaning and truth becomes a positive manifestation of this otherness as truth itself. Thus the historical “truths” of the grotesque are superseded by history itself. When the expressions of the grotesque solidify into static form and meaning, they become mere objects like anything else in the world. Instead of being this elusive thing of process and flow, it becomes tangible to the existing hierarchy of power as well as history itself. In this way the grotesque can be expunged, included or simply revealed as yet another false notion of truth, which is precisely what has happened with the grotesque throughout the course of history. If from the beginning the expression of the grotesque has not already been in the service of some structure of meaning and truth, it has quickly been included or has quickly included itself in such a structure. But by doing so it rejects its own basis: the tension between periphery and center is replaced by the attempt to create a new center, a new structure of meaning and truth. The doubleness, ambiguity and flow of the grotesque are then rejected by the grotesque itself. THE NON-FORM OF FORM In the critical thinking of Theodor W. Adorno (1903-69) the problem of art, caught between a reductive and prevalent notion of truth and meaning and a peripheral and alienated otherness, is reexamined and reformulated. For Adorno, the instrumental rationality of Enlightenment itself reverts into a new form of mythology which is every bit as static and exclusive as the hierarchies of religion it supersedes. All is excluded that is non-identical to the instrumental mastery of the objects of the world, "For the Enlightenment, anything which cannot be resolved into numbers, and ultimately into one, is illusion; modern positivism consigns it to poetry." 1 As such the non-identical has been banished from the realm of thought and action, and banished specifically to the realm of art. But the realm of art is not able to provide a decent home for it because even modern art is not something entirely autonomous. While it is excluded from the notions of truth and meaning provided by instrumental rationality, it still originates from society. Just like instrumental rationality art is about mastery, structuring and exclusion. Therefore, the problem for art is that it cannot directly provide a space for the non-identical because its mode of operation is similar to that of instrumental rationality. Even worse, art has very few possibilities to free itself from this. If it becomes l’art pour l’art it is at the same time reduced to the very thing instrumental rationality claims it to be: a subjective judgment of taste.expressionism also stands as an example of this. Conversely, art cannot work within the framework of the identity-thinking of society, because any notion of freedom or emancipation would reproduce the exclusive practices of instrumental rationality. For example: Explicit socialist literature may establish itself in opposition to instrumental rationality while at the same time reproducing it. Its language may seem different, but in reality it merely provides a different set of reductive schematics for human life and experience. The problem for the art of the grotesque was, as I mentioned earlier, that far too often it was merely a symbolic manifestation of a notion of otherness—not otherness itself. Because of this the subversive character of the grotesque ends up shaping and containing otherness instead of providing a space for it. According to Adorno the only way to avoid this is to radicalize the grotesque. In order to avoid solidifying into form the work of art has to be an object which cannot be contained in thought or form—a non-form of form. The work of art has to work in a way that it strives for autonomy but without entirely leaving a discernible reality. In other words, it has to pull in two directions at once. Thus the work of art is a paradox. It is autonomous in the sense that it closes itself off from everything outside of the work of art, trying to shy away from the contaminating influence of the identity thinking of instrumental rationality. At the same time though the work of art is heteronomous in the sense that it originates from a specific historical context and is bound to be what society is not. Autonomy and heteronomy are inseparably intertwined. Unable to display otherness itself, but still trying to be a refuge for it, there is only one option for art: It has to turn against itself and destroy its own logic of form, thereby demonstrating how any representation of otherness is impossible. Art becomes a lamentation of the victims of the identity thinking of instrumental rationality and shows the traces of the otherness that is unable to appear. Adorno’s pessimistic theory of art and history stages art as a negative dialectical process where the work of art closes itself off and rejects everything outside, while the individual elements in the work of art destroys its very own logic of form from within: Artworks synthetize ununifiable, nonidentical elements that grind away at each other; they truly seek the identity of the identical and nonidentical processually because even their unity is only an element and not the magical formula of the whole […]. The resistance to them of otherness, on which they are nevertheless dependent compels them to articulate their own formal language, to leave not the smallest unformed particle as remnant. This reciprocity constitutes art’s dynamic; it is an irresolvable antithesis that is never brought to rest in the state of being. 2 Relative to a traditional understanding of the grotesque, Adorno radicalizes the tension between center and periphery, autonomy and heteronomy. In the traditional understanding of the grotesque, as we find it for example in the writings of Mikhail Bakhtin, the grotesque establishes the display of otherness as a new center of meaning and truth. However Adorno rejects such notions and argues instead for a modernism of the grotesque in which both center and periphery are included in a negative dialectical process and continually synthesizing and destabilizing each other’s positions. A modernism of the grotesque works on the inside of the sign or the artwork, continually outlining and questioning the boundaries between materiality and form. This moves the focus away from the relation between the sign or work of art as a conceptual manifestation on one side and the object it refers to on the other side. Instead it implicitly points to the amorphous mass from which the signs and thereby meaning have been carved, the remnants that have been left behind. Modernism of the grotesque does not imply that it is emancipatory or that it reconciles man with nature, and does not represent a new position or a new ideology. It merely remembers and insists on the double nature of man and art: to write or paint yourself or an artwork whole by inscribing meaning in life or by applying form on a canvas is at the same time both creation and destruction. The very signs we use to center meaning in our lives carry its own alienation in them. Meaning surfaces only when process and flow comes to a halt—solidifying, but at the same time excluding parts that do not fit into that particular structure of meaning. NOTHING DONE AND NOTHING UNDONE It has always been difficult for art historians to find a suitable category for the works of the Danish artist Leif Lage (b. 1933). In his paintings the sensitive figuration seems so fragile that it is on the verge of turning into abstraction. Or conversely: the figurative emerges cautiously and hesitantly out of abstraction. As an art critic once wrote, he can almost paint things away. 3 Working in some undefinable space between abstraction and figuration, the Lage’s works shy away from the realm of words, and as a result few critics have been able to write anything meaningful about his works. In fact even fewer have been able to write more than one or two pages. The Danish author and art critic Leif Hjernøe is one of those few, but even he starts off by saying how impossible it is to write about Lage, confessing that his works exist both as process and in a field of in-between which words cannot reach. He writes: Always you find yourself in a place where nothing is done and nothing left undone, and where the elements of the work of art rest in a continuous motion. Always there is the open wound, where infection rather than surgical intervention is considered as an opportunity. And the conflict between matter and antimatter makes all diagnoses uncertain and allows conditions of uncertainty to spread in a place of raw presence. 4 The art works against the diagnosis and the certainty. Words are being eaten up by what is outside the realm of words: tension, process and doubleness. An approach to an understanding of the work of Lage could be to follow his connection to Samuel Beckett (1906-89). One can note, therefore, that Lage has illustrated several of the Danish translations of Beckett’s works. Though one is an author and the other a painter both seek a place where figuration, where the word, erodes. For both this entails an attempt to question and examine and so move in behind the façade of the surface in an exploration of that something or nothing that may be behind representation. At the same time even in the vanishing point of figuration or words, the meaningless words or the disjointed lines still stand as signs of human activity—signs of movement in emptiness. With very few exceptions Lage’s artworks revolve around one motif: Man—most often “en face.” But unlike traditional portraitures Lage’s people are found within. The artworks do not sense the reality of appearances, but rather the existential dimensions within man. As a seismograph they are sensitive to the utmost subjectivity in order to display an objective, sensuous depiction of the very problem of subjectivity. Instead of a static façade of a man, Lage’s “en face” shows the process-character of man. The people in Lage’s paintings are always in process—in the midst of becoming or dissolving. I will take a closer look in the following at the ways in which Lage establishes this sense of being in constant process, of being in-between modes or categories. THE DOUBLENESS OF THE STROKE Lage’s etchings attract attention in particular for the tension conveyed there between the material and the form. The material physically opposes the violence of the needle. But instead of embracing the violence of the needle and the victory over matter—instead of making the artistic creation and figuration express a heroic mastery of the background it is made out of—Lage uses the stroke to express the very tension between stroke and material, figuration and background. In the drypoint etching Untitled from 1983, which illustrated the Danish translation of Beckett’s Ill Seen, Ill Said , the needle tears up the material in long rough lines: Together, the primarily horizontal and vertical lines form a face. Thus the force needed to etch a line in the metal-plate draws attention to itself: It is there in the absence of curves and nuances. Man emerges on the metal-plate after great exertion and in a very simplistic form. This way Lage enhances the nature of the material, as the material’s resistance is not something to overcome. On the contrary the figuration is smitten by its very resistance and as such expresses the violence of its own becoming. Even more pronounced is the fact that the lines do not just show the violence of creation—it actively erases figuration in the same process that creates it. For example the mouth consists of 8-10 horizontal strokes, of which some seem to be connected to each other as if the mouth has been quickly scratched out. The mouth speaks of the inability to speak. In the same way, the eyes are black holes due to a large amount of criss-cross cuts, which together form a dark middle. Those lines, at the same time, form the eyes of the figuration and scratch out the eyes of the figuration. The extroverted aspects of the face—connected to speech and sight—are portrayed as introverted as well. Just as the etchings down into the metal-plate makes something appear. Leif Lage, Untitled , 1983 (etching) The figuration of the etching is connected to creation. It expresses that something is wrought into existence out of nothing by sheer artistic force. However, this force is at the same time presented as a violence of creation, which makes it impossible for form to truly emerge. Herein lies one of the basic principles of Lage’s art, namely that art cannot be that nothing or something behind the realm of words or signs. Without form, art would lose its ability to express anything at all. Form is a necessity if art is to avoid becoming as devoid of expression as the reality is that we cannot reach behind the appearance of things. On the other hand, art cannot raise itself above its own material in joyous celebration of the beauty of form. This would use the material in the manner of an instrument and thus would suppress the otherness it attempts to rescue. When art becomes mere form, any traces of otherness will have dissolved. Then art would be a question of technique, in no way different from the instrumental rationality of society. Therefore art works in a particular space between form and non-form. As Hjernøe says of the works of Lage, it is in the center of the event, in the in-between where things neither are nor are not, "And everything takes place just before it changes character. As the blood just before it coagulates, as the milk just before it separates, as fried egg just before it turns white […]." 5 The precise emphasis on the in-between of Lage’s art points in particular to the work of art as both outside of and in time. The work of art is a singular point in time, but at the same time it is continually in process. In the borderland between form and non-form, between creation and destruction, it shimmers like a fata morgana . The work is done but at the same time undone. It is only there as a cry in response to the inability to come into being. Akin to the etching is the drawing, but while both, of course, use the stroke or line as their main instrument, the paper does not resist the line in the same sense as the metal-plate of the etching. As a result in Lage’s drawings the stroke frolics in a space with almost no tension at all. There is nothing there to keep the pencil stroke at bay, but at the same time this means that there is nothing there to keep it together. One of the more expressive examples of this is found in an untitled drawing from Tegninger og Text ( Drawings and Text ) from 1999. The drawing consists of one unbroken pencil stroke. It is as if the stroke is confused—it darts around on the paper making doodles on the way or gathers itself in more straight lines in the center of the paper. It is in this manner that the semblance of a body is established. A couple of small circles serve as eyes and are the reason that the rest can be read as both face and body instead of pure abstraction. In fact the unbroken stroke serves as both abstraction and figuration as on the one hand it is the stroke that seemingly outlines the shape of a figure, while on the other hand the unbroken stroke dissolves any truly recognizable figuration by continuously, without end or aim, overflowing the boundaries of the figure. Seen again here is a doubleness to the stroke and the act of creation. In the etching it was all about the tension between the resistance of the material which created the doubleness. Here it is the opposite. It is the lack of tension. The stroke is free to do anything, but has no aim: without some kind of resistance, there is nothing to hold figuration together. It threatens to dissolve into nothingness. Conversely, the drawing can also be seen as a process of becoming. Like a form of automatic writing, the pencil darts around until it finds a point of densification. But even in such an interpretation of the drawing, the figuration appears artificial—it points to itself as the result of the artistic act of creation. The stroke is primarily stroke and only secondarily figuration. With its wild movement it calls attention to itself as stroke. Thus the figuration never becomes something in its own right. It points to the basic principle of creation: Someone has drawn me, I am the result of artistic endeavors, and therefore I am not for myself but always overflowing the boundaries that contain me. It is the stroke that in the very same movement creates figuration and dissolves it. Leif Lage, Untitled , 1999 (drawing) THE LIGHTNESS OF COLOR, THE DENSITY OF PAPER Often the watercolor is used as a precursor for larger paintings, because it has an immediacy in which one can quickly paint the main lines of a composition. However, Lage’s watercolors are not temporary points in a process leading to another final painting. They are not sketches, later to be filled with details in another material. For him watercolor is an end in itself. This also implies that he doesn’t try to work against the paper’s absorption of the water color and its tendency to absorb detail. On the contrary, he examines the possibilities inherent in this blurring of the line and absorption of color. As in the previous examples, there are of course recognizable shapes in Lage’s water colors. But these shapes are rarely separable from color, line or even paper. In other words: the figurative and the abstract more or less become one. One of the reasons for this is that Lage often works on wetted paper which means that the paper hungrily absorbs color into its fabric instead of it being on top of the paper. The paper becomes line because it is the absorption of the color which, together with the brush stroke itself, separates the colors from each other. The line is also color and the color is also line, because there is no separation between the different colors other than the colors themselves. At times this results in almost complete abstraction. In such cases Lage add lines with a pencil as if he wants to hold some sort of figuration together. At other times it is the other way around: the strokes of the pencil are a being dissolved by the water color blurring out the figuration. Untitled 1 from 1999 displays various tones of green. The contour of the colors appears unusually rough. Most of all it is reminiscent of a shoreline which has found its form through the work of thousands of years between water and land. Pockets of resistance surface as islands not yet drowned in color—as paper or color not yet consumed by the dominant color. The shape of the colors does not seem created by the hand of the artist, but rather by the inner workings of the watercolor: color against color over time has resulted in this very image, as if it is all a part of a natural process of change and decay. Despite the fact that there are no strong differences in color there seems to be a struggle taking place in the watercolor. For example, inexplicable holes in the dark color, which cover most of the right side of the watercolor, appear as if the underlying color is eating away the dark color, or that the dark color is in the process of covering up the underlying color. The small pockets of resistance demonstrate a process and development that, almost as a happy accident, evokes a couple of small eyes and a large mouth. Behind the colors a few slanted lines can be discerned, but the hand of the artist has long ago disappeared behind the life of the colors. Thus the watercolor seems to be held at precisely the point in time where figuration randomly appears. The small eyes and wide mouth seemingly express the realization of the figuration’s temporality. It is just a moment in time, soon to be consumed again in the life of the colors. The nature, the background it stems from and is part of, moves on undeterred, continuing its everlasting process of creation and decay. In this sense, the watercolor provides an experience of how neither artist nor man is able to transcend the materiality they consist of. The colors of man, the materials man consists of are “becoming” and “progress” but also “decay” and “disappearance”. The artist’s pencil strokes have been eaten up long ago, and the figuration is living on borrowed time. Human or artistic activity is about creating form, transcending mere matter by shaping and applying meaning to it. But Untitled 1 shows the doubleness of such creation: the transience and fragility of human life. Should the figuration come into being, should it rise and transcend the material, which binds it to its temporal existence, it would become nothing because its very existence is conditioned by the life and work of the colors. In the same sense man cannot escape his own temporality. He too, for better or worse, must accept a life in the volatility of sensation. Leif Lage, Untitled 1 , 1999 (watercolor) In most of Lage’s watercolors there seem to be a stronger artistic control than in Untitled 1 . Most often both the arrangement of colors and the technique in which they are painted express the hand of the artist. An example of this is Untitled 2 from 1999. While figuration in Untitled 1 seemed to appear as a happy accident, the figuration is much more “created” in Untitled 2 . Here the most important parts of the figuration, the eyes, the mouth and part of the skull, are colored black and painted on top of the background’s play of colors. The background primarily consists of blue and yellow tones. Only parts of the paper are covered in color, however, which yet again stresses the act of painting: There is a surface which is being filled by color by an artist. The blue tones are concentrated in the figuration, while the yellow tones surround it. All this means that the figuration stands out more clearly in this watercolor. This is also underlined by the fact that the blue and dark tones cover part of the yellow tones as spots here and there. Thus it is not a background which is in the process of consuming figuration, but rather the emerging figuration which blots out the background. Such an understanding is even suggested by how the mouth and eyes are placed in the larger blue color field. The eyes and mouth are in the center of the watercolor, while the blue color field is placed from center out towards the left side. This gives the impression of a face turned slightly to the right and slightly upwards, which again makes the mouth appear to emerge from the paper. It also helps that the mouth cuts the center axis of the watercolor. In other words, the arrangement of the blue and black colors create some depth and perspective which gives the illusion of a figuration, seen partially in profile, emerging from the background. Seen in profile, the eyes and mouth seem extroverted—they almost seem as if they are put on top of the face. But at the same time they are painted as black holes, sucking in the gaze of the onlooker. The watercolor is even more challenging if one follows what may be the faint outline of the skull, which, on the right side of the watercolor, no longer works together with the blue color, but rather alone postulates the outline of the skull. If not the blue color field, but this line, is the outline of the skull, then all of a sudden the face is not in profile but “en face”—staring directly towards the onlooker. Outline and color seemingly work against each other and establish two different expressions. Without the slightly upward tilted expression of the profile, the eyes and mouth do not seem to emerge from the paper. On the contrary, seen “en face,” the eyes and mouth are really gaping pits of darkness. In this sense Untitled 2 is at the same time surface and depth of perspective. The line gives form but at the same time it dissolves the form created by the colors, and vice versa. Leif Lage, Untitled 2 , 1999 (watercolor) As the last example of Lage’s artistic method, I have chosen another untitled work (as indeed nearly all of Lage’s artworks are)—this time from 2000. This is perhaps one of the most figurative watercolors Lage has created, though that doesn’t tell us too much. The painting depicts a human face in blue and green tones on a yellow toned background. The colors create a clear demarcation between the figure and the background, which compensate for the watercolor’s lack of outline. Beneath the face darker tones imply the beginning of the torso, and nuances of color even hint at something which could be a collar. The hair is in even darker tones and its structure is emphasized using pencil strokes on top of the water color. One eye is marked by a brown spot with a darker spot in the middle, while the other eye is added by pencil. The mouth is a round, red dot. In Untitled from 2000 the work between abstraction and figuration is much less pronounced than in the previous examples cited here. Nonetheless the watercolor has a delicacy to it which almost makes the figuration disappear, even as it appears. This has something to do with the fact that all the individual brush strokes have dissolved. The only outlines are those created by the clash of colors. Even the red mouth seems to be more paint than mouth—unable to be formed truly as anything other than a speck of color with some small semblance to a mouth. In contrast to the other watercolors, there is no movement, no progress or decay, just a vibrating standstill. The figure is not emerging or disappearing but embedded in and as surface, and as such it makes the figure seem stuck in its condition rather than freed by the act of giving form: mouth open as a wound. Pencil strokes add detail and life to the hair as an attempt to help the figure emerge. But all this does is create two levels in the watercolor: The pencil strokes are put on top of the figuration rather than being part of it. Thus they end up highlighting the endless distance between the movement and form-giving of the pencil strokes and the static and stuck figure behind these strokes. Leif Lage, Untitled , 2000 (watercolor) MAN AND THE VIEW OF THE ONLOOKER Lage’s works seem at the same time to be an examination of tensions between form and material in art and a display of an image of man full of the same tensions. This is because the people who are emerging in Lage’s images are not just in his works, They are his works. This means that man is not something emerging from a background but is part of this background and vice versa. The art of Lage inscribes man in its surroundings and background. Man is not the ruler of nature. Man does not rise above matter; there is no truly transcendent position for man to occupy in the art of Lage. Instead man is a part of the very matter, it, at the same time, tries to distance itself from in order to distinguish itself from its surroundings. Man emerges in an attempt not to be line, stroke, color. In an attempt to free itself of matter. Should it succeed in this, however, it would turn into nothing. On the other hand, if man fully accepted itself as mere matter it would disappear in it—in instincts, urges and lack of reflection. The appearance of man is thus subject to a state of being in-between. Only in the tension between material and its negation can the outlines of man be traced. However this also means that in the art of Lage man is never something in itself but always in process—on the way to its freedom and its loss. However, Lage’s art is not just about showing the tensions inherent in man but also about showing such tension on the verge of breaking point. In the moment before everything is done, or when nothing yet has been done, the delicate tension between form and material has been stretched to its utmost in such a way that man’s character of process emerges and is contained on the paper or canvas. Therefore, Lage’s art contain traces of human life. Not only is it an autonomous unity of tensions where man is stretched out between its singularity and the surroundings it is a part of. It is also this pulsation between figuration and material which brings about the traces of human endeavor and activity. Even when man almost seems to have disappeared into the material, strokes and lines are still there as a reminder of human activity and potential creative power—as a reminder that hope is still possible and that man is still there. The view of the onlooker seeks out forms and meaning. It seeks outlines and edges. But first and foremost it is the eyes in Lage’s works of art that allow the onlooker to decode the figuration at play. This creates a distinctive relationship between the onlooker and the artwork. The onlooker tries to wrest the enigma from the artwork, tries to reduce it to solid, meaningful form. But the very same moment that hints at such a possibility sees the view of the onlooker confronted with a gaze of its own. The eyes of the figure in the work of art are most often dark pits, as if they were an illustration of the violence committed against the eyes of the onlookers and their search for meaning. Or as if they were a dark reflection of the onlooker’s failed attempts to delineate the traces of life in the artwork to a solid meaningful form. Therefore, the gaze of the figuration speaks not only of its own powerlessness but also of the powerlessness of the onlooker. When the view or sight has trouble finding solid meaningful forms, it has something to do with the fact that the precondition for sight, light, no longer stems from something transcendent. In Lage’s art there is nothing outside the works of art, nothing outside of human life, and as such nothing to shed light on the works of art or human life and reveal solid meaningful forms. All light comes from within. In a western context, light as a medium for sight is central to the understanding of meaning. People speak of the clarity of thought, while knowledge is tied together with enlightenment, and so forth. But the light no longer originates from a divine point of view. It originates from man, who has created himself in the image of God. The problem with this is that light always covers up its own base. Light illuminates something but at the same time it hides itself. 6 While it was previously God who was unknowable, now it is man. It is also problematic that sight and the medium of sight stem from the same place. Following this thought one can posit two final problems. Firstly, the immediacy and presence established by light by making forms and objects accessible to sight is fake. Light is not some independent entity which present things in a neutral manner for the onlooker. It is inextricably tied together with the gaze’s desire after meaning. In other words: Light perverts the appearance of things because it doesn’t originate from some objective entity which allows them to appear as they are. Instead light is based upon and originates from the subject and its conquering gaze, seeking out meaning and form constantly. Secondly, the joining of sight and light makes introspection within human life impossible. Everything can be illuminated by its use value for the subject but only as long as it is separated from the subject, as long as it is an object. But the subject itself cannot be illuminated. Lage’s art tears down such a dividing line between subject and matter, but it does so without reestablishing a divine position from where the light emanates. Therefore, the light in Lage’s art may not illuminate very well. It may not have the certainty presented by modern science or the religions of yesterday. But it does show what such light tries to hide, namely, the subject as it is in its material reality—inscribed in time and death, which are the basic conditions of materiality, but at the same time also full of life in its joy and will to create. For the onlooker the meeting of the gaze in Lage’s works of art is thus also a destruction of the view of the onlooker. The ability to see is challenged in a radical way. Those outlines will not solidify into static form, as if the light was too dim to see. Just as in Lage’s figurations, the view of the onlooker turns to black: turns towards the onlooker in recognition and becoming—or disappearance. NOTES Max Horkheimer and Theodor W. Adorno. Dialectic of Enlightenment . (Palo Alto: Stanford University Press, 2002): 4-5. Theodor W. Adorno. Aesthetic Theory . (London & New York, 2002): 176. Carsten Bach-Nielsen. “Mere glæde end gru.” Kristeligt Dagblad . September 24, 2002. Leif Hjernøe. “Den yderliggående inderlighed.” LEIF LAGE—Retrospektiv udstilling 1983 . (Copenhagen: Brøndum, 1983): 18. Ibid. Maurice Blanchot. The Infinite Conversation . (Minneapolis: University of Minnesota Press, 1993): 162-163. (shrink)

Suppose your evil sibling travels back in time, intending to lethally poison your grandfather during his infancy. Determined to save grandpa, you grab two antidotes and follow your sibling through the wormhole. Under normal circumstances, each antidote has a 50% chance of curing a poisoning. Upon finding young grandpa, poisoned, you administer the first antidote. Alas, it has no effect. The second antidote is your last hope. You administer it---and success: the paleness vanishes from grandpa's face, he is healed. (...) As you administered the first antidote, what was the chance that it would be effective? -/- This essay offers a systematic account of this case, and others like it. The central question is this: Given a certain time travel structure, what are the chances? In particular, I'll develop a theory about the connection between these chances and the chances in ordinary, time-travel-free contexts. Central to the account is a Markov condition involving the boundaries of spacetime regions. (shrink)

This paper deals with those time travels mostly considered by physics, namely those in the form of the so-called closed timelike curves. Some authoritative scholars have raised doubts about the status of these journeys as proper time travels. By using David Lewis’ famous definition of time travels proposed in 1976, we show that this proper status may actually be recovered, at least in some cosmological contexts containing spacetime regions, such as those concerning black holes described (...) by the Kerr–Newman metric, that allow the formation of local closed curves. But, the mathematical incompatibility between ordinary black hole solutions to Einstein field equations and the cosmological solutions induces us to take into consideration the more general issue pertaining to the slippery interplay between models related to local and global aspects of the world, highlighting, in particular, the different notions of time that these domains inevitably imply. This leads us to think that time is not a univocal entity of the world, but is a scale-related characteristic which claims the adoption, when investigating its ontological status, of a sort of regional approach. We also briefly dwell upon the most appropriate form of realism that such a kind of dispute between local and global models may involve. (shrink)

I argue that David Lewis’s philosophically dominant conception of time travel cannot straightforwardly handle what we might call cases of relativistic time travel—that is, the sort of time travel which could only plausibly occur in a relativistic setting. I evaluate whether or not the Lewisian account can be successfully adapted such that it would able to analyse potential cases of relativistic time travel satisfactorily while still being employable in the analysis of those cases that make no (...) mention of physics or the structure of spacetime. This is primarily an analytical and explanatory exercise, rather than a polemical one. (shrink)

The physical possibility of spacetimes containing closed timelike curves (CTCs) challenges the philosophy of time in the way that temporal ordering is, at best, remarkably non-standard: events on CTCs precede themselves. Apparently, such universes do not possess a consistent time order but only a consistent time direction. Thus, temporal directionality seems to be more fundamental than ordering in earlier-later or past-present-future. I will argue that this favors presentism as the adequate ontology of spacetimes: only presentism (...) consistently copes with the idea that temporal ordering depends on empirical constraints. The presentist Now is fundamentally undivided and productively directed towards existence. Time order arises by extending the Now, which can fail and in fact fails in universes containing CTCs. (shrink)

This chapter explores the concept of time itself, as physicists understand it. Einstein's special theory of relativity requires worldlines of physical objects to be timelike; the field equations of his general theory of relativity predict that massive bodies such as stars and black holes distort space‐time and bend worldlines. Suppose space‐time becomes so distorted that some worldlines form closed loops. If one tried to follow such a closed timelike curve (or CTC) exactly, all the way (...) around, one would bump into ones former selves and get pushed aside. But by following part of a CTC, we could return to the past and participate in events there. According to a recent calculation by J. Richard Gott of Princeton, a cosmic string passing rapidly by another would generate CTCs. The chapter concludes that if time travel is impossible, then the reason has yet to be discovered. (shrink)

Recent years have seen a growing consensus in the philosophical community that the grandfather paradox and similar logical puzzles do not preclude the possibility of time travel scenarios that utilize spacetimes containing closed timelike curves. At the same time, physicists, who for half a century acknowledged that the general theory of relativity is compatible with such spacetimes, have intensely studied the question whether the operation of a time machine would be admissible in the context of (...) the same theory and of its quantum cousins. A time machine is a device which brings about closed timelike curves—and thus enables time travel—where none would have existed otherwise. The physics literature contains various no-go theorems for time machines, i.e., theorems which purport to establish that, under physically plausible assumptions, the operation of a time machine is impossible. We conclude that for the time being there exists no conclusive no-go theorem against time machines. The character of the material covered in this article makes it inevitable that its content is of a rather technical nature. We contend, however, that philosophers should nevertheless be interested in this literature for at least two reasons. First, the topic of time machines leads to a number of interesting foundations issues in classical and quantum theories of gravity; and second, philosophers can contribute to the topic by clarifying what it means for a device to count as a time machine, by relating the debate to other concerns such as Penrose's cosmic censorship conjecture and the fate of determinism in general relativity theory, and by eliminating a number of confusions regarding the status of the paradoxes of time travel. The present article addresses these ambitions in as non-technical a manner as possible, and the reader is referred to the relevant physics literature for details. (shrink)

Most approaches to quantum gravity suggest that relativistic spacetime is not fundamental, but instead emerges from some non-spatiotemporal structure. This paper investigates the implications of this suggestion for the possibility of time travel in the sense of the existence of closed timelike curves in some relativistic spacetimes. In short, will quantum gravity reverse or strengthen general relativity’s verdict that time travel is possible?

Recent debates about inequality have focused almost exclusively on the distribution of wealth and disparities in income, but little notice has been paid to the distribution of free time. Free time is commonly assumed to be a matter of personal preference, a good that one chooses to have more or less of. Even if there is unequal access to free time, the cause and solution are presumed to lie with the resources of income and wealth. In Free (...) Time, Julie Rose argues that these views are fundamentally mistaken. First, Rose contends that free time is a resource, like money, that one needs in order to pursue chosen ends. Further, realizing a just distribution of income and wealth is not sufficient to ensure a fair distribution of free time. Because of this, anyone concerned with distributive justice must attend to the distribution of free time. On the basis of widely held liberal principles, Rose explains why citizens are entitled to free time—time not committed to meeting life's necessities and instead available for chosen pursuits. The novel argument that the just society must guarantee all citizens their fair share of free time provides principled grounds to address critical policy choices, including work hours regulations, Sunday closing laws, public support for caregiving, and the pursuit of economic growth. Delving into an original topic that touches everyone, Free Time demonstrates why all citizens have, in the words of early labor reformers, a right to "hours for what we will.". (shrink)

Already in 1835 Lobachevski entertained the possibility of multiple geometries of the same type playing a role. This idea of rival geometries has reappeared from time to time but had yet to become a key idea in space-time philosophy prior to Brown's _Physical Relativity_. Such ideas are emphasized towards the end of Brown's book, which I suggest as the interpretive key. A crucial difference between Brown's constructivist approach to space-time theory and orthodox "space-time realism" pertains (...) to modal scope. Constructivism takes a broad modal scope in applying to all local classical field theories---modal cosmopolitanism, one might say, including theories with multiple geometries. By contrast the orthodox view is modally provincial in assuming that there exists a _unique_ geometry, as the familiar theories have. These theories serve as the "canon" for the orthodox view. Their historical roles also suggest a Whiggish story of inevitable progress. Physics literature after c. 1920 is relevant to orthodoxy primarily as commentary on the canon, which closed in the 1910s. The orthodox view explains the spatio-temporal behavior of matter in terms of the manifestation of the real geometry of space-time, an explanation works fairly well within the canon. The orthodox view, Whiggish history, and the canon have a symbiotic relationship. If one happens to philosophize about a theory outside the canon, space-time realism sheds little light on the spatio-temporal behavior of matter. Worse, it gives the _wrong_ answer when applied to an example arguably _within_ the canon, a sector of Special Relativity, namely, _massive_ scalar gravity with universal coupling. Which is the true geometry---the flat metric from the Poincare' symmetry group, the conformally flat metric exhibited by material rods and clocks, or both---or is the question faulty? How does space-time realism explain the fact that all matter fields see the same curved geometry, when so many ways to mix and match exist? Constructivist attention to dynamical details is vindicated; geometrical shortcuts can disappoint. The more exhaustive exploration of relativistic field theories in particle physics, especially massive theories, is a largely untapped resource for space-time philosophy. (shrink)

Contemporary philosophy realizes that time, like language and embodiment, is not an obstacle to truth and reality but one of its primary mediums. Time is dimensionality, past, present, future, and directionality, before and after. Politics has its own temporality. Conservatives aim to restore a selected past; progressives to create a better future; and authoritarians to reinforce the present status quo. In each case, however, the dominant temporal dimension is the future. Time, as Levinas has shown, is (...) also inter-subjective, that is to say, social, and as such also ethical. Hence, in some important sense politics is a struggle over time, a contention between its dimensions, to select a past, to close off a present, or to create a future. This helps us to better understand our contemporary political triangulation of liberalism, socialism and fascism. The peculiarity of fascist politics, and key to its negativity and viciousness, is that it rejects history altogether, past and future, preferring the frenzy of the moment, the violent delirium of immanence, to the short- and long-term responsibilities of justice, liberal or social. (shrink)

We address the question of whether it is possible to operate a time machine by manipulating matter and energy so as to manufacture closed timelike curves. This question has received a great deal of attention in the physics literature, with attempts to prove no- go theorems based on classical general relativity and various hybrid theories serving as steps along the way towards quantum gravity. Despite the effort put into these no-go theorems, there is no widely accepted definition (...) of a time machine. We explain the conundrum that must be faced in providing a satisfactory definition and propose a resolution. Roughly, we require that all extensions of the time machine region contain closed timelike curves; the actions of the time machine operator are then sufficiently "potent" to guarantee that closed timelike curves appear. We then review no-go theorems based on classical general relativity, semi-classical quantum gravity, quantum field theory on curved spacetime, and Euclidean quantum gravity. Our verdict on the question of our title is that no result of sufficient generality to underwrite a confident "yes" has been proven. Our review of the no-go results does, however, highlight several foundational problems at the intersection of general relativity and quantum physics that lend substance to the search for an answer. (shrink)

A conceptual model of a partnership in ‘like-minded thinking’ consists of the following components: a relationship, a shared goal with mutual agreement to work toward that goal, and reciprocal encouragement between two people. A like-minded alliance is a relationship that offers support while at the same time encourages hope and establishes a reciprocating emotional attitude of hopefulness.The discussion focuses on the principles of such a model that is designed primarily as a lay intervention for anyone who has (...) a close friend with cancer and who wants to assist the friend in maintaining a hopeful attitude in the face of illness. While this model is not directed at healthcare professionals it may be transferable into psychosocial interventions to assist persons toward sustaining hopefulness in the context of the cancer trajectory. Much has been written in the literature about how hopelessness spawns despair for individuals who have cancer and in those near the end of life; it may even create a desire for hastened death (Breitbart W., Heller K.S.: 2003, ‘Reframing Hope: Meaning-Centered Care for Patients Near the End of Life; Journal of Palliative Medicine 6, 979–988; Jones J.M., Huggins M.A., Rydall A.C., Rodin G.M.: 2003, ‘Symptomatic distress, hopelessness, and the desire for hastened death in hospitalized cancer patients’ Journal of Psychosomatic Research 55, 411–418).Therefore, the aim of this paper is to explore how like-minded thinking for a person with cancer and his or her support person provides a framework for a personal shared worldview that is hope-based, meaningful and coherent. (shrink)

The topic is time travel of the sort depicted in H. G. Wells’ classic novel, The Time Machine—Wellsian time travel. The range of proper applicability of the concept of Wellsian time travel is investigated. The results of this investigation are applied to provide a new argument against the metaphysical possibility of time travel in absolute time. Alternatively, the argument is against the possibility of Wellsian time travel relative to a single temporal frame of (...) reference. The argument leaves open the prospect that an object nontrivially moves relative to one temporal reference frame from one time to another relative to another temporal reference frame. The argument does not turn on closed timelike curves or “causal loops” of any kind. It does however invoke the prospect of backward causation—a consequence of backward time travel in conjunction with common sense—but it invokes this possibility only in the weak sense of mere logical consistency. (shrink)

This paper is a survey of the theories of time travel in a perspective close to theories of time. In the last section we discuss the special ontology of the objects that exist on closed timelike curves. We simply assert that CTC need a new ontology and these objects are not simply impossible or unconcevaible.

The article presents an analysis of the main aspects of the Christian theology of childhood based on the works of outstanding theologians of the 20th century: Dietrich Bonhoeffer, Hans Urs von Balthasar, Karl Rahner, Paul Tillich, and Jurgen Moltmann. The preoccupation with understanding the figure of the child in Western Christianity is motivated by several factors: the undeniable importance of theology as a tradition of interpreting the existential constraints of the human condition, the deep influence of Christian teaching on secular (...) concepts of childhood, as well as the need to stand in defense of theological knowledge against its reactionary appropriation. It is proposed to begin reflection on the problems of the theology of childhood with the question of secularization, which Bonhoeffer characterized as the world's coming of age. The symptoms of such maturation are a crisis of responsibility in an atomized society, powerlessness, and despair from being doomed to remain in a self-closed system moving towards its own destruction. In the eyes of theologians, the figure of the child turns out to be a symbol of the incompleteness of the history of the world and, in the context of Christian eschatology, of the possibility of saving humanity. For a world that has lost its historical dimension, the child comes across, in Moltmann's words, as a metaphor of hope. Theology emphasizes the intrinsic value and uniqueness of every individual childhood experience, while at the same time seeing it as an analogy of the universal relationship between the human community and God. The model of this relationship implies not only acceptance of the world and its law, but also reprehension leading to liberation from the law in divine love. In theological interpretations the Christian imperative to be like children appears as the cornerstone of universal ethics and political practice, which is necessary for humanity to overcome the catastrophic historical situation. (shrink)

Here we provide a proof that there exist closed timelike curves in Gödel spacetime with total acceleration less than 2π(9 + 6√3)^1/2. This answers a question posed by David Malament.

The most potentially powerful objection to the possibility oftime travel stems from the fact that it can, under the right conditions, give rise to closedcausal loops, and closed causal loops can be turned into self-defeating causal chains;folks killing their infant selves, setting out to destroy the world before they were born,and the like. It used to be thought that such chains present paradoxes; the receivedwisdom nowadays is that they give rise to physical anomalies in the form of inexplicably (...) correlated events. I argue against the received wisdom. I can find nothing in them that argues against the possibility (even, the probability) of time travel. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Homeric Allusions at the Close of Thucydides' Sicilian NarrativeJune W. Allison.(Marcellinus Vita Thucydidis 37)When Thucydides composed his history, the inclusion of elements from epic was natural. Both the subjects and compositional techniques of epic were at home in this evolving genre.1 Herodotus' mighty prose epic, with its own debts to Homer, was the culmination of the process, successfully combining the mythic and epic with historical narrative.2 Thucydides' method, however, (...) was going to be different: the mythic was to be done away with and the epic made to serve the account of the most destructive war in historical memory.Thucydides in some places mentions Homer directly and in others makes artful allusions to Homeric epic.3 In his Archaeology he repeatedly [End Page 499] holds up the Trojan War as the first great naval expedition and records its failings. In his programmatic passages, moreover, Thucydides draws comparisons between Homer's methods and his own.4 Marcellinus, his biographer, reflects a tradition that attributed even individual features of Thucydides' style and language to Homer. Epic conventions abound: there are angry speeches between antagonists; there are catalogues of warriors, in particular, the fine example before the final battle at Syracuse (7.57–59); and there are splendid battle scenes, where individuals, such as Brasidas, are singled out.5 When Thucydides turns to compose the events of the Sicilian Expedition, he allows the reader to dwell on parallels between it and its ancestral expedition to Troy.6 The parallels with the Homeric poems on a thematic level are large and obvious: a monumental Greek naval expeditionary force travels far in order to besiege a city. The insistence in book 6 on heavy preparations for Sicily recalls Thucydides' criticism in book 1.9 of Agamemnon's effort. Unlike their poetic ancestors, who prolonged the siege because they had to spend valuable time gathering supplies by means of raids on nearby cities, the Athenians would take their necessities with them. Like the Iliad, the History has war as its pervading theme, but also like the Iliad, it is not simply about war; rather it is about the human motivations and reactions which that most dehumanizing phenomenon elicits. In depicting what is poignant Thucydides competes with Homer. He [End Page 500] does not fail to draw on the values of the Iliad to highlight his own narrative and to imbue his account with the powerful sensitivity to suffering found in both Homeric poems.My focus in these pages is Thucydides' use of Homeric words in his description of the final battle in the great harbor and the retreat of the Athenians from Sicily. In 1900 Smith collected some of these terms but made no claims for completeness: "A few terms and idioms borrowed from poetry and traceable directly or indirectly to Homer may give some idea of what might be found if one knew classical Greek usage thoroughly well and were perfectly familiar with Homer" (70).7 So it is not easy to pinpoint specific verbal allusions to Homer in the History. The historian may have used other works in the epic cycle or tragedies now lost that made use of epic.8 Moreover, the atmosphere of high poetry we encounter may result from the effect of a few words or even one word or a setting which will recall Homer without, however, alluding to a specific passage in the poems.9 The poetic influence upon prose was long and profound. Indeed, prose of the fifth century had not yet totally divorced itself from poetry. What I suggest here is that Thucydides created an atmosphere in the final chapters on the Sicilian disaster which derives its Homeric aura from a number of attributes, among these, words of epic coloring.In two places Thucydides seems to make conspicuous use of Homer: in the Funeral Oration, and at the end of book 7. The Funeral Oration deserves analysis, but because it is a formal, epideictic, state address over fallen warriors and is traditional (as Pericles says repeatedly), [End Page 501] it attracts epic forms, as it were, by nature. I shall concentrate on book 7, where Thucydides has employed Homeric echoes to enhance in... (shrink)

I argue that Deutsch’s model for the behavior of systems traveling around closed timelike curves relies implicitly on a substantive metaphysical assumption. Deutsch is employing a version of quantum theory with a significantly supplemented ontology of parallel existent worlds, which differ in kind from the many worlds of the Everett interpretation. Standard Everett does not support the existence of multiple identical copies of the world, which the D-CTC model requires. This has been obscured because he often refers to (...) the branching structure of Everett as a “multiverse”, and describes quantum interference by reference to parallel interacting definite worlds. But he admits that this is only an approximation to Everett. The D-CTC model, however, relies crucially on the existence of a multiverse of parallel interacting worlds. Since his model is supplemented by structures that go significantly beyond quantum theory, and play an ineliminable role in its predictions and explanations, it does not represent a quantum solution to the paradoxes of time travel. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Time and History in Alois Riegl's Theory of PerceptionMichael GubserIn an early essay, the Austrian art historian Alois Riegl (1858–1905), a pioneer of the modern discipline of art history, linked the creation of the zodiac images in calendar art to the designation of constellations in the heavens.1 Ancient calendar artists observed the motion of stars across the night sky and attempted to map them into recognizable patterns representing (...) specific temporal periods. Their efforts inscribed the cyclical temporality of the heavens into the images of the ancient calendar. This inherent temporality came to characterize all art forms in Riegl's work; his choice of calendar art as his earliest research topic heralded a career-long interest in the connection between temporality and artistic form. Art objects, he believed, were temporal as well as spatial. Just as the light from constellations reflected a deep history, artworks illuminated the passage of time by visually re-presenting the perceptual world of past eras.Riegl's work has garnered attention in recent decades among art historians and non–art historians alike. This interest is due in part to the renewed concern for disciplinary origins that art history, like other fields, has experienced in the wake of poststructuralist critiques. Scholars outside of art history have taken note of his work because of its broad scope and relevance for the study of historiography and perception; Riegl's work provides models for linking the analysis of specific artworks with a history of perception, exploring the relationship between monuments and memory, and analyzing the nature of visual modernity. Interest in Riegl also stems from his acknowledged impact on such preeminent philosophers and historical theorists as Erwin Panofsky, Paul Feyerabend, Gilles Deleuze, Fèlix Guattari, and above all Walter [End Page 451] Benjamin.2 Figures as varied as Georg Lukács, Karl Mannheim, Walter Gropius, and Mikhail Bakhtin have cited his work favorably.3 Riegl is perhaps best known for his attempts to dismantle the hierarchy of high and low art, his attack on the preeminence of classical aesthetic ideals, and his effort to construct a universal history of style. The combination of these commitments led him to consider European and non-European craft genres that fell outside conventional definitions of art. In books such as Problems of Style, Late Roman Art Industry, and The Group Portraiture of Holland, Riegl examined the high arts, decorative arts, and manufactured artifacts alike, gleaning insights into the structure of an era's perception from close descriptive analyses of its artwork.4 In Problems of Style, Riegl traced the development of ancient vegetal decorative motifs toward their fulfillment in the naturalized tendrils and acanthus leaves of Greek ornament. A single, universal development encompassed seemingly distinct motivic forms, and creative innovation was driven by an inner formal logic. Similarly, Late Roman Art Industry, the [End Page 452] epoch-making work that Walter Benjamin described as a revolution in art historical method,5 traced the gradual development of space as an object of artistic concern in the late Roman Empire. In this volume, Riegl explored his controversial notion of the Kunstwollen, or artistic will, which asserted art's autonomy on the basis of a formal creative volition internal to artworks.6 Finally, The Group Portraiture of Holland documented the emergence and decline of a "typically Hollandish painting" emphasizing space and attention.7Riegl scholars have frequently attempted to situate his art history within a variety of philosophical traditions, an effort complicated by Riegl's limited citation of sources. Several scholars have linked Riegl's historical vision with the embattled tradition of Hegelian philosophy. Riegl's teleology; his stress on the unified, internal, and purposive development of art; his notion of art as mind overcoming material; and even his emphasis on the role of the viewer in art all have a distinctly Hegelian resonance. Wolfgang Kemp fits Riegl squarely within a late-nineteenth-century Hegelian revival,8 Michael Podro incorporates him within a Hegelian critical tradition of art history that spanned the nineteenth and early twentieth centuries,9 and Michael Ann Holly posits a clear trajectory, linking Kant and Hegel with Riegl and Panofsky.10Others, however, just as firmly reject this... (shrink)