Kuera, A., On relative randomness, Annals of Pure and Applied Logic 63 61–67. It is the aim of the paper to answer a question raised by M. van Lambalgen and D. Zambella whether there can be a nonrecursive set A having the property that there is a set B such that B is 1-random relative to A and simultaneously A is recursive in B. We give apositive answer to this question as well as further information about relative randomness.

It has been repeatedly argued, most recently by Nicholas Maxwell, that the special theory of relativity is incompatible with the view that the future is in some degree undetermined; and Maxwell contends that this is a reason to reject that theory. In the present paper, an analysis is offered of the notion of indeterminateness (or "becoming") that is uniquely appropriate to the special theory of relativity, in the light of a set of natural conditions upon such a notion; (...) and reasons are given for regarding this conception as (not just formally consistent with relativity theory, but also) philosophically reasonable. The bearings upon Maxwell's program for quantum theory are briefly considered. (shrink)

Define z to be the smallest cardinality of a function f: X → Y with X. Y ⊆ 2ω such that there is no Borel function g ⊇ f. In this paper we prove that it is relatively consistent with ZFC to have b < z where b is, as usual, smallest cardinality of an unbounded family in ωω. This answers a question raised by Zapletal. We also show that it is relatively consistent with ZFC that there exists X ⊆ (...) 2ω such that the Borel order of X is bounded but there exists a relatively analytic subset of X which is not relatively coanalytic. This answers a question of Mauldin. (shrink)

Adams and Dziobiak proved that any finite-to-finite universal quasivariety must be Q-universal, and then asked whether a somewhat weaker hypothesis could lead to the same conclusion. We show that their original hypothesis cannot be weakened to its naturally extreme form.

We consider the following question within both Newtonian physics and relativity theory. "Given two point particles X and Y, if Y is rotating relative to X, does it follow that X is rotating relative to Y?" As it stands the question is ambiguous. We discuss one way to make it precise and show that, on that reading at least, the answers given by the two theories are radically different. The relation of relative orbital rotation turns out to be symmetric (...) in Newtonian physics, but not in relativity theory. (shrink)

Peter Klein claims to have explicated the notion of relative certainty and shown how it is related to the notion of absolute evidential certainty in his book Certainty. I argue that he has not succeeded at this because the account of relative certainty provided only applies to a subset of the pairs of propositions about which we make judgments of relative certainty.

"Reflections on Relativity" is a comprehensive presentation of the classical, special, and general theories of relativity, including in-depth historical perspectives, showing how the relativity principle has repeatedly inspired advances in our understanding of the physical world.

We introduce a notion of relative efficiency for axiom systems. Given an axiom system Aβ for a theory T consistent with S12, we show that the problem of deciding whether an axiom system Aα for the same theory is more efficient than Aβ is II2-hard. Several possibilities of speed-up of proofs are examined in relation to pairs of axiom systems Aα, Aβ, with Aα ⊇ Aβ, both in the case of Aα, Aβ having the same language, and in the case (...) of the language of Aα extending that of Aβ: in the latter case, letting Prα, Prβ denote the theories axiomatized by Aα, Aβ, respectively, and assuming Prα to be a conservative extension of Prβ, we show that if Aα — Aβ contains no nonlogical axioms, then Aα can only be a linear speed-up of Aβ; otherwise, given any recursive function g and any Aβ, there exists a finite extension Aα of Aβ such that Aα is a speed-up of Aβ with respect to g. (shrink)

John MacFarlane has made relativism popular again. Focusing just on his original discussion, I argue that the data he uses to motivate the position do not, in fact, motivatie it at all. Many of the points made here have since been made, independently, by Hermann Cappelen and John Hawthorne, in their book Relativism and Monadic Truth.

Relative Identity contains a sustained attack on the classical or absolute theory of identity and a defense of a non-classical or relative theory of identity. According to the absolute theory of identity each thing is identical with itself and with nothing other than itself. The fundamental principle of this theory is Leibniz' Law:From a variety of characteristic principles about identity can be derived, including The Indiscernibility of Identicals, The Identity of Indiscernibles, and the symmetry, reflexivity, and transitivity of identity.

In “Unarticulated Comparison Classes” 2018 [2009], Richard Vallée adopts John Perry’s (2012 [2001]) reflexive-referential theory of meaning and content as well as his concept of unarticulated constituents (Perry 1986) to deal with certain context-sensitive elements of the truth-conditions of statements containing relative gradable predicates. I am sympathetic both with the general framework and with the assumption that unarticulated constituents are involved in the truth-conditions of bare positives such as “Monica is tall.” I do not share, however, Vallée’s main conclusions on (...) the examples he provides as pre-theoretical evidence. This leads me to disagree with some details of his proposal for the semantics and pragmatics of relative gradable adjectives. (shrink)

In a recent paper, Howard Stein makes a number of criticisms of an earlier paper of mine ('Are Probabilism and Special Relativity Incompatible?', Phil. Sci., 1985), which explored the question of whether the idea that the future is genuinely 'open' in a probabilistic universe is compatible with special relativity. I disagree with almost all of Stein's criticisms.

Work in the setting of the recursively enumerable sets and their Turing degrees. A set X is low if X', its Turning jump, is recursive in $\varnothing'$ and high if X' computes $\varnothing''$ . Attempting to find a property between being low and being recursive, Bickford and Mills produced the following definition. W is deep, if for each recursively enumerable set A, the jump of $A \bigoplus W$ is recursive in the jump of A. We prove that there are no (...) deep degrees other than the recursive one. Given a set W, we enumerate a set A and approximate its jump. The construction of A is governed by strategies, indexed by the Turning functionals Φ. Simplifying the situation, a typical strategy converts a failure to recursively compute W into a constraint on the enumeration of A, so that $(W \bigoplus A)'$ is forced to disagree with Φ(-; A'). The conversion has some ambiguity; in particular, A cannot be found uniformly from W. We also show that there is a "moderately" deep degree: There is a low nonzero degree whose join with any other low degree is not high. (shrink)

As Einstein’s successor in Prague and the author of a biography on Einstein, the physicist and philosopher Philipp Frank made relativity a central aspect of his thoughts on morality. He published his views on this topic mainly in the year 1950 in a small book entitled Relativity—A Richer Truth. As far as morality as a part of social and political life is concerned, Frank’s primary interest is to show that as in science, relativity in morality does not (...) preclude objectivity. The paper deals with the question of which conceptions of relativity and relativism Frank refers to in the context of modern science and examines the implications for objectivity and absolute values in morality. (shrink)

Let \({\mathcal {K}}\) be a quasivariety. We say that \({\mathcal {K}}\) is a term quasivariety if there exist an operation of arity zero _e_ and a family of binary terms \(\{t_i\}_{i\in I}\) such that for every \(A \in {\mathcal {K}}\), \(\theta \) a \({\mathcal {K}}\) -congruence of _A_ and \(a,b\in A\) the following condition is satisfied: \((a,b)\in \theta \) if and only if \((t_{i}(a,b),e) \in \theta \) for every \(i\in I\). In this paper we study term quasivarieties. For every \(A\in (...) {\mathcal {K}}\) and \(a,b\in A\) we present a description for the smallest \({\mathcal {K}}\) -congruence containing the pair (_a_, _b_). We apply this result in order to characterize \({\mathcal {K}}\) -compatible functions on _A_ (i.e., functions which preserve all the \({\mathcal {K}}\) -congruences of _A_) and we give two applications of this property: (1) we give necessary conditions on \({\mathcal {K}}\) for which for every \(A \in {\mathcal {K}}\) the \({\mathcal {K}}\) -compatible functions on _A_ coincides with a polynomial over finite subsets of _A_; (2) we give a method to build up \({\mathcal {K}}\) -compatible functions. (shrink)

In 'An undermining diagnosis of relativism about truth', Horwich claims that the notion of relative truth is either explanatorily sterile or explanatorily superfluous. In the present paper, I argue that Horwich's explanatory demands set the bar unwarrantedly high: given the philosophical import of the theorems of a truth-theoretic semantic theory, Horwich's proposed explananda, what he calls acceptance facts, are too indirect for us to expect a complete explanation of them in terms of the deliverances of a theory of meaning based (...) on the notion of relative truth. And, to the extent that there might be such an explanation in certain cases, there is no reason to expect relative truth to play an essential, ineliminable role, nor to endorse the claim that it should play such a role in order to be a theoretically useful notion. (shrink)

In their recent paper, Jackson and Pargetter have attempted to prove that simultaneity is not a matter of convention. They attempt to show that it is an empirical fact whether or not a moving rod A′B′ is perpendicular to a plane XY. If it is an empirical fact, then such a perpendicular rod can be used to synchronize clocks. We shall show that it is not an empirical fact, but it is in fact synchronization dependent.

The A-theory of time has intuitive and metaphysical appeal, but suffers from tension, if not inconsistency, with the special and general theories of relativity (STR and GTR). The A-theory requires a notion of global simultaneity invariant under the symmetries of the world's laws, those ostensible transformations of the state of the world that in fact leave the world as it was before. Relativistic physics, if read in a realistic sense, denies that there exists any notion of global simultaneity that (...) is invariant under the symmetries of the world's laws. If physics is at least a decent guide to metaphysics--as sympathies for scientific realism would suggest--then relativistic physics supports the B-theory. If there were a physically natural way to modify the symmetries of the physical laws so as to remove those that are repugnant to the A-theory, while retaining empirical adequacy, then such an altered physics might be attractive to the A-theorist and would weaken the support given by relativity to the B-theory. I exhibit a way to do so here, displaying a Lagrangian density explicitly containing distant simultaneity, yet implying Einstein's field equations. The modification involves a change in the nature of the lapse function and makes use of the Dirac-Bergmann formalism of constrained dynamics, which recently has been discussed much by John Earman. Here this formalism is adapted slightly to permit both local and global generalized coordinates. A classification of senses in which time might be absolute or not is made along the way. Some suggestions for extending the work by finding a first principles motivation are made. An appendix outlines an argument why many local presents are insufficient and a global present is attractive, while two more appendices review the Dirac-Bergmann apparatus for GTR and then apply it to the theory at hand. (shrink)

Let d be a Turing degree, R[d] and Q[d] denote respectively classes of recursively enumerable (r.e.) and all degrees in which d is relatively enumerable. We proved in Ishmukhametov [1999] that there is a degree d containing differences of r.e.sets (briefly, d.r.e.degree) such that R[d] possess a least elementm $>$ 0. Now we show the existence of a d.r.e. d such that R[d] has no a least element. We prove also that for any REA-degree d below 0 $'$ the class (...) Q[d] cannot have a least element and more generally is not bounded below by a non-zero degree, except in the trivial cases. (shrink)

A [1983] review, 'Relativity before Einstein' made no mention of the work of Joseph Larmor, whose early derivation of the Lorentz transformation seems to be less well known than those of Lorentz and Poincare. In 1897, Larmor, starting from a first-order transformation similar to Lorentz's first order version, presented the correct form of what is now known as the Lorentz transformation. In his presentation of the theory in 1900 Larmor saw the time dilation effect as a consequence of Maxwell's (...) electromagnetic theory. It was Lorentz who, in 1895, introduced the notion of the relativity of simultaneity (local time), without the time dilation effect. Poincare in 1900 discussed how Lorentz's local time would arise from the procedure of synchronizing moving clocks by exchanging light signals assumed to travel at the same speed in either direction. Lorentz presented the correct version of the transformation in 1899, and discussed the variation of mass with velocity arising from it. In 1902 Lorentz was aware of Larmor's 1897 work but apparently missed its significance. Nevertheless, the credit for the first presentation of the Lorentz transformation including the crucial time dilation belongs to Larmor. (shrink)

In a recent paper M.R. Ayers attacks two widely held doctrines: Non-arbitary individuation requires principles of individuation and these are supplies only by sortal general terms. It is possible for an item a to be the same as b but not the same as b.I shall follow Ayers in calling a theory which includes both and ‘conceptualist’ or ‘sortalist’, but I shall not allow him to appropriate the honorific term ‘realist’ for his own theory, which I shall term ‘absolutist’. My (...) sole purpose here is to defend and in turn against Ayers’ attacks on them. Thus I shall ignore intermediate positions which accept but reject or vice-versa.Ayers’ paper is long and in many respects obscure; there are many points in it which require discussion but which can't receive it here for lack of space. In particular, I shall ignore his lengthy comments on the constitutive ‘is’, and also the wider metaphysical remarks in his conclusion and the postscript on Dummett. (shrink)

This essay has two related contentions. First, by examining two early Qing exegetical works on the Great Learning, one by Chen Que (陳確 1604-77) and another by Li Guangdi (李光地 1642-1718), the essay reveals that Confucian hermeneutics was essentially moral philosophy. Exegesis of the classics was an occasion for speculative thinking on the normative, the axiological, and the anthropological. The embedding of moral philosophy in hermeneutics meant that it was animated by the search for and affirmation of truths, rather than (...) by the construction and application of theories of understanding. Second, it argues that Confucian engagement with the classics, as with all acts of reading, is subject to the tyranny of the hermeneutic imperative, the self-evident priciple that all thoughts involve interpretation and are relative to the contingent context of particular historical forces and factors, especially the interpreter's preunderstanding. To the extent that the acts of reading and interpreting inexorably forge a dialogical relation between the text and the reader, and since understanding is a universal element in this relation, the nature of Confucian hermeneutics may be fruitfully and comparatively pondered with reference to some contemporary theories, Gandamer's in particular. This essay contends that in the final analysis, Gadamerian hermeneutics exemplifies the Western philosophical predilection to reduce engagement with reality to the search for an analytical method/theory, whereas the Confucian counterpart is metapractical in intent and substance, broadly philosophical for its ontological confrontation with reality as an integrated whole. (shrink)

Wheat is the most imperative crop for man feeding and is planted in numerous countries under rainfed conditions in semiarid zones. It is necessary for decision-makers and governments to predict the yield of rainfed wheat before harvest and to determine the effect of the major factors on it. Different methods have been suggested for forecasting yield with various levels of accuracy. One of these approaches is the statistical regression model, which is simple and applicable for regions with scarce data available. (...) Since the weather is the most important factor affecting the production of wheat, particularly in rainfed cultivation, regression models using weather parameters are very common. However, the coefficients of these models are location based and should be determined locally. Therefore, in this research, backward multiple linear regression technique based on relative importance metrics was used to determine the most important effective weather parameters on rainfed wheat productions in Fars Province, south of Iran, during 2006–2013. The influence of each parameter in the final model was analyzed using the values of LMG relative importance metric. The result indicated that sunshine hours had the biggest LMG and, therefore, was the most effective parameter. Also, among the other considered parameters, rainy days, minimum relative humidity, and average relative humidity with LMG values of 21.97%, 21.69%, and 21.62%, respectively, had the most effects on rainfed wheat yield in the studied area. All parameters except for the sunshine hours positively affected rainfed wheat yield. The most important reason for the significance of these parameters can be the prevailing dry and semidry climate in the southern areas of Iran. The proposed model for determination of weather parameters effects on rainfed wheat could be a great guidance and aid for different stakeholders such as farmers, decision-makers, and governments. (shrink)

Weinberg's 1972 work, in his description, had two purposes. The first was practical to bring together and assess the wealth of data provided over the previous decade while realizing that newer data would come in even as the book was being printed. He hoped the comprehensive picture would prepare the reader and himself to that new data as it emerged. The second was to produce a textbook about general relativity in which geometric ideas were not given a starring role (...) for (in his words) too great an emphasis on geometry can only obscure the deep connections between gravitation and the rest of physics. (shrink)

ObjectiveRelative deprivation is associated with collective and individual variables in psychology. However, so far, there are few studies on measuring the relative deprivation of university students. Therefore, this study designs the University Students’ Relative Deprivation Questionnaire, verifies its validity and reliability, and then uses it to measure the mental health of students.MethodsAfter reviewing the relevant studies and conducting a theoretical analysis and an open questionnaire survey, this article determined the structural dimension of USRDQ. A total of 103 university students were (...) selected to take the open questionnaire survey, 200 were selected to engage in the item analysis, exploratory factor analysis, and internal consistency reliability test, 257 were selected to engage in the confirmatory factor analysis, and 287 were selected to take the retest reliability.ResultsThe USRDQ includes 19 items under the three dimensions, namely, social comparison, cognitive evaluation, and emotional experience. Factor loads range from 0.49 to 0.87, which accounted for 63.39% of the total variation. The questionnaire has good fitting indicators. The Cronbach’s α coefficient of the questionnaire is 0.916, and the coefficients of the three factors range from 0.805 to 0.934. The results of the survey show that the relative deprivation of students is quite high with a mean of 76.78 and a standard deviation of 16.96. (shrink)

In 1922 the University of Buenos Aires (UBA) Council approved a motion to send an invitation to Albert Einstein to visit Argentina and give a course of lectures on his theory of relativity. The motion was proposed by Jorge Duclout (1856–1927), who had been educated at the Eidgenössische Technische Hochschule, Zurich (ETH). This proposal was the culmination of a series of initiatives of various Argentine intellectuals interested in the theory of relativity. In a very short time Dr. Mauricio (...) Nirenstein (1877–1935), then the university's administrative secretary, fulfilled all the requirements for the university's invitation to be endorsed and delivered to the sage in Berlin. The visit took place three years later, in March–April 1925. (shrink)

By focusing on players’ relative contributions, we study some properties for values in positive cooperative games with transferable utilities. The well-known properties of symmetry (also known as “equal treatment of equals”) and marginality are based on players’ marginal contributions to coalitions. Both Myerson’s balanced contributions property and its generalization of the balanced cycle contributions property (Kamijo and Kongo Int J of Game Theory 39:563–571, 2010; BCC) are based on players’ marginal contributions to other players. We define relative versions of marginality (...) and BCC by replacing marginal contributions with relative contributions, and examine efficient values satisfying each of the two properties. On the class of positive games, a relative variation of marginality is incompatible with efficiency, and together with efficiency and the invariance property with respect to the payoffs of players under a player deletion, a relative variation of BCC characterizes the proportional value and egalitarian value in a unified manner. (shrink)

According to T. M. Scanlon's buck‐passing account, the normative realm of reasons is in some sense prior to the domain of value. Intrinsic value is not itself a property that provides us with reasons; rather, to be good is to have some other reason‐giving property, so that facts about intrinsic value amount to facts about how we have reason to act and to respond. The paper offers an interpretation and defense of this approach to the relation between reasons and values. (...) I start by acknowledging the role that substantive values play in specifications of our reasons, noting that this poses an apparent challenge to the buck‐passing account. The challenge can be met, however, if we adopt a deliberative understanding of substantive value, an interpretation that I proceed to develop and defend. In conclusion I consider recent attempts to capture the agent‐relativity of reasons within a teleological framework for thinking about the relation between reasons and values. I argue that these approaches rest on a deliberative understanding of value; the teleological framework thus turns out to illustrate the basic insight of the buck‐passing approach, rather than offering an alternative to it. (shrink)

This article examines changes in employed African American mothers' use of relatives for child care. Data from nationally representative pooled cross sections show that the proportion of Black mothers relying on extended kin for care of their preschool-age children declined significantly between 1977 and 1994. Multivariate analyses reveal that the decline characterized all subgroups of employed African American mothers but was less pronounced for young, single, mothers living outside the South. Thus, by 1994, employed Black mothers who most needed relatives' (...) child care support received it, while those who could manage without such help did so. This change suggests that African Americans' use of kin-provided support responds to shifts in broader social and economic conditions that affect the balance of resources and needs within extended families. (shrink)