The phenomenon of probability backflow, previously quantified for a free nonrelativistic particle, is considered for a free particle obeying Dirac's equation. It is shown that probability backflow can occur in the opposite direction to the momentum; that is to say, there exist positive-energy states in which the particle certainly has a positive momentum in a given direction, but for which the component of the probability flux vector in that direction is negative. It is shown that the maximum possible amount of (...) probability that can flow “backwards,” over a given time interval of duration T, depends on the dimensionless parameter ε = (4ℏ/mc2T)1/2, where m is the mass of the particle and c is the speed of light. At ε = 0, the nonrelativistic value of approximately 0.039 for this maximum is recovered. Numerical studies suggest that the maximum decreases monotonically as ε increases from 0, and show that it depends on the size of m, ℏ, and T, unlike the nonrelativistic case. (shrink)

gl. 1. Geopoliticheskai︠a︡ determinat︠s︡ii︠a︡ kulʹtury i ėkonomiki. Rolʹ geograficheskikh faktorov v razvitii obshchestva ; Geopoliticheskie osobennosti sot︠s︡iokulʹturnoĭ istorii Rossii -- gl. 2. Kulʹturnai︠a︡ sostavli︠a︡i︠u︡shchai︠a︡ geopolitiki. Kulʹtura kak instrument geopolitiki ; Dialog kulʹtur v sovremennom mire: opasnai︠a︡ illi︠u︡zii︠a︡, otchai︠a︡nnai︠a︡ vera ili velenie vremeni?

Different approaches have been proposed in order to achieve knowledge integration for coronary care monitoring applications, usually in the form of expert systems. The clinical impact of these expert systems, which are based only on "shallow" knowledge, has not been remarkable due to the difficulties associated with the construction and maintenance of a complete knowledge base. Model-based systems represent an alternative to these problems because they allow efficient integration of the "deep" knowledge on the underlying physiological phenomena being monitored. In (...) this work, a brief review of existing model-based systems for cardiac rhythm interpretation is presented, followed by the description of a new system forCardiac Arrhythmia Recognition by Model-Based ECG Matching (CARMEM). Fundamental characteristics of CARMEM are presented; in particular, its ability to provide on-line parameter adaptation to simulate complex rhythms and to match observed ECG signals. The proposed model can be useful for the explanation of the origin of cardiac arrhythmias and contribute towards their robust characterization in the context of coronary care units. (shrink)

1. The present paper is a continuation of my “Self-Ownership, World Ownership, and Equality,” which began with a description of the political philosophy of Robert Nozick. I contended in that essay that the foundational claim of Nozick's philosophy is the thesis of self-ownership, which says that each person is the morally rightful owner of his own person and powers, and, consequently, that each is free to use those powers as he wishes, provided that he does not deploy them aggressively against (...) others. To be sure, he may not harm others, and he may, if necessary, be forced not to harm them, but he should never be forced to help them, as people are in fact forced to help others, according to Nozick, by redistributive taxation. (shrink)

Some ways of defending inequality against the charge that it is unjust require premises that egalitarians find easy to dismiss—statements, for example, about the contrasting deserts and/or entitlements of unequally placed people. But a defense of inequality suggested by John Rawls and elaborated by Brian Barry has often proved irresistible even to people of egalitarian outlook. The persuasive power of this defense of inequality has helped to drive authentic egalitarianism, of an old-fashioned, uncompromising kind, out of contemporary political philosophy. The (...) present essay is part of an attempt to bring it back in. (shrink)

The logical status of abstraction principles, and especially Hume’s Principle, has been long debated, but the best currently availeble tool for explicating a notion’s logical character—permutation invariance—has not received a lot of attention in this debate. This paper aims to fill this gap. After characterizing abstraction principles as particular mappings from the subsets of a domain into that domain and exploring some of their properties, the paper introduces several distinct notions of permutation invariance for such principles, assessing the philosophical significance (...) of each. (shrink)

In this stimulating work of political philosophy, acclaimed philosopher G. A. Cohen sets out to rescue the egalitarian thesis that in a society in which distributive justice prevails, peopleâes material prospects are roughly equal. Arguing against the Rawlsian version of a just society, Cohen demonstrates that distributive justice does not tolerate deep inequality. In the course of providing a deep and sophisticated critique of Rawlsâes theory of justice, Cohen demonstrates that questions of distributive justice arise not only for the state (...) but also for people in their daily lives. The right rules for the macro scale of public institutions and policies also apply, with suitable adjustments, to the micro level of individual decision-making. Cohen also charges Rawlsâes constructivism with systematically conflating the concept of justice with other concepts. Within the Rawlsian architectonic, justice is not distinguished either from other values or from optimal rules of social regulation. The elimination of those conflations brings justice closer to equality. (shrink)

I argued in Karl Marx's Theory of History that the central claims of historical materialism are functional explanations, and I said that functional explanations are consequence explanations, ones, that is, in which something is explained by its propensity to have a certain kind of effect. I also claimed that the theory of chance variation and natural selection sustains functional explanations, and hence consequence explanations, of organismic equipment. In Section I I defend the thesis that historical materialism offers functional or consequence (...) explanations, and I reject Jon Elster's contention that game theory can, and should, assume a central role in the Marxist theory of society. In Section II I contrast functional and consequence explanation, thereby revising the position of Karl Marx's Theory of History, and I question whether evolutionary biology supports functional explanations. Section III is a critique of Elster's views on functional explanation, and Sections IV and V defend consequence explanation against metaphysical and epistemological doubts. A concluding section summarizes my present understanding of the status of historical materialist explanations. (shrink)

John Rogers explores the concepts of recognition, command and authority and tests their validity in several cases presented by Hobbes, ranging from parental authority to the omnipotence of God. The general thesis he defends is that, for Hobbes, autonomy always goes hand in hand with the possession of power. Even for the individuals in a civil society, there is no autonomy but in a condition of empowerment. But, at the same time, the strength of the laws of nature rests in (...) their rationality, and there can be no doubt that their compelling force comes from their being rational. The comparison with mathematical theorems furnishes an important element of understanding, since the laws of nature are conclusions concerning that which conduces to the conservation of oneself. Although there is an empirical element in the deduction of those practical theorems, this is no objection to the analogy being drawn, since this empirical element belongs to the learning process and not to the rationality of the law itself. In the light of this conception of natural law, Hobbes thus appears as a rationalist in morals and politics. (shrink)