In quantum field theory, coherent states can be created that have negative energy density, meaning it is below that of empty space, the free quantum vacuum. If no restrictions existed regarding the concentration and permanence of negative energy regions, it might, for example, be possible to produce exotic phenomena such as Lorentzian traversable wormholes, warp drives, time machines, violations of the second law of thermodynamics, and naked singularities. Quantum Inequalities have been proposed that restrict the size and duration of the (...) regions of negative quantum vacuum energy that can be accessed by observers. However, QIs generally are derived for situations in cosmology and are very difficult to test. Direct measurement of vacuum energy is difficult and to date no QI has been tested experimentally. We test a proposed QI for squeezed light by a meta-analysis of published data obtained from experiments with optical parametric amplifiers and balanced homodyne detection. Over the last three decades, researchers in quantum optics have been trying to maximize the squeezing of the quantum vacuum and have succeeded in reducing the variance in the quantum vacuum fluctuations to \ dB. To apply the QI, a time sampling function is required. In our meta-analysis different time sampling functions for the QI were examined, but in all physically reasonable cases the QI is violated by much or all of the measured data. This brings into question the basis for QI. Possible explanations are given for this surprising result. (shrink)

Having defined a notion of homology for paired graphs, Métayer ([Ma]) proves a homological correctness criterion for proof nets, and states that for any proof net \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $G$\end{document} there exists a Jordan-Hölder decomposition of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\mathsf H}_0(G)$\end{document}. This decomposition is determined by a certain enumeration of the pairs in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $G$\end{document}. We correct (...) his proof of this fact and show that there exists a 1-1 correspondence between these Jordan-Hölder decompositions of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\mathsf H}_0(G)$\end{document} and the possible ‘construction-orders’ of the par-net underlying \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $G$\end{document}. (shrink)

It is being increasingly recognized that the Saussurean dictum of “the arbitrariness of the linguistic sign” is in conflict with the pervasiveness of the phenomenon commonly known as “sound symbolism”. After first presenting a historical overview of the debate, however, we conclude that both positions have been exaggerated, and that an adequate explanation of sound symbolism is still lacking. How can there, for example, be (perceived) similarity between expressionsand contents across different sensory modalities? We offer an answer, based on the (...) Peircian notion of iconic ground, and G. Sonesson’s distinction betweenprimary and secondary iconicity. Furthermore, we describe an experimental study, in a paradigm first pioneered by W. Kohler, and recently popularized by V.Ramachandran, in which we varied vowels and consonants in fictive word-forms, and conclude that both types of sounds play a role in perceiving an iconic ground between the word-forms and visual figures. The combination of historical conceptual analysis, semiotic explication and psychological experimentationpresented in this article is characteristic of the emerging paradigm of cognitive semiotics. (shrink)

Das vorliegende Buch versucht in einer systematischen Ge­ samtübersicht den Gedankeninhalt der modernen Physik zu er­ läutern. Mit Einzelheiten der experimentellen Technik sollte der Leser dabei ebensowenig belastet werden, wie mit den mathe­ matischen Formulierungen der Theorie; ohne uns zu sehr in der Fülle betrachtenswerter Einzelheiten zu verlieren, wollen wir unsere Aufmerksamkeit auf die entscheidenden Tatsachen und Einsichten, auf die leitenden Gesichtspunkte der Forschung richten - und auf die geistige Einstellung, welche der modernen Physik ihr charakteristisches philosophisches Gepräge gibt, und (...) welche die Erringung ihrer umstürzenden Erkenntnisse ermög­ licht hat. Wir beginnen mit einer nachdenklichen Betrachtung der klassischen G a I i I e i - N e w t o n sehen Mechanik, deren Sinn und Bedeutung eindringlich verstanden zu haben Vorbedin­ gung ist für jedes Verständnis der revolutionären Entwicklungen der modernen Physik. Uber die Gedankengänge der M a x w e l- sehen Elektrodynamik kommen wir sodann zu den modernen Er­ kenntnissen, sowohl in der "Makrophysik", als auch in der "Mikro­ physik" der Atome, Elektronen und Quanten. Daß die moderne physikalische Forschung zu revolutionären Umgestaltungen der traditionellen naturwissenschaftlichen Vor­ stellungen geführt hat, wird der Leser hier keineswegs zum ersten­ mal erfahren. Aber nicht nur der lockende Reiz dieser wunder­ baren Entwicklungen schien mir eine auch dem Nichtspezialisten zugängliche Darstellung wünschenswert zu machen, sondern ich wünschte auch einen Beitrag zu leisten zur allmählichen Besei­ tigung von Mißverständnissen, denen die neueste Entwicklung der Physik bei manchem Fernerstehenden ausgesetzt gewesen ist. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Hume, Tillotson, and Dialogue XIIJeff JordanJeff JordanUniversity of DelawareFootnotes1. 'Natural religion' in the seventeenth and eighteenth centuries denoted knowledge of the divine which could be had via reason or instinct, independent of any purported special revelation.2. Of the two best works on Hume's philosophy of religion, J. C. A. Gaskin, Hume's Philosophy of Religion (Atlantic Highlands, New Jersey, 1988); and K. Yandell, Hume's "Inexplicable Mystery": His Views on Religion (...) (Philadelphia, 1990), only the first examines Hume's critique of the argument from prudence at all (see Hume's Philosophy of Religion, 194-203); but Gaskin's treatment of Hume's critique leaves untouched several important elements of the critique.3. B. Pascal, Pensées, ed. L. Lafuma, trans. J. Warrington (1670; reprint, London, 1960), 92-96.4. On Locke, see Essay Concerning Human Understanding (1690), bk. 2, chap. 21. On Leibniz, see Die Philosophischen Schriften, 3:621. On Craig, see Theologiae Christianae Principia Mathematica (1699), chap. 6. On Paley, see A View of the Evidences of Christianity (1795), pt. 3, chap. 8.5. Tillotson, "The Wisdom of Being Religious," Sermon 1 in Works of Tillotson (London, 1820), 1:317-89 (hereafter cited as W).6. I do not mean to suggest that Hume was aware only of the sermon "The Wisdom of Being Religious," but that Hume was aware of Tillotson's claims and arguments as found in several of his sermons. "The Wisdom of Being Religious" is important because (i) it is explicitly mentioned by Hume in his A Letter From A Gentleman to His Friend in Edinburgh (1745; reprint, Edinburgh, 1967), 23, so we know that Hume had read this sermon; (ii) it was one of the best known of Tillotson's sermons; and (iii) it contains all of the elements of Tillotson's argument from prudence.7. T. Birch, "Life of the Author," in Works of Tillotson, 1:xix-xx. See also L. G. Locke, Tillotson (Copenhagen, 1954).8. Tillotson may have been aware of the Port Royal Logic version of the wager through Locke with whom Tillotson was in correspondence. See Tillotson, 83.9. Tillotson's case for (1) is treated extensively in his sermon, "The Advantage of Religion to Societies," Sermon 3 in Works of Tillotson, 1:409-23.10. In the passage quoted (W 361-62), Tillotson claims that the atheist will naturally dread a superior being who can defeat one's plans and judge one's actions.11. See also "The Efficacy, Usefulness, and Reasonableness Of Divine Faith," Sermon 223 in Works of Tillotson, 9:258-79. The idea of a grand lie is first found in Plato; see Republic 3:389, 414, 5:459.12. "Pascalian Wagering," Canadian Journal of Philosophy 16, no. 3 (1986): 437-54.13. Though Tillotson mentions "odds" and "hazards," he does not incorporate probability values in his version of the wager. His wager is a decision under uncertainty and not a decision under risk: he does not, that is, calculate the expected utility of theistic belief. Pascal was the first to formulate the wager as a decision under risk where the probability-weighted averages of the utility values (the expected utility) determine the right choice.14. Of course, these principles were not stated explicitly until much later. See Ian Hacking, The Emergence of Probability (London, 1975).15. For an example of the many-gods objection, see M. Martin, Atheism: A Philosophical Justification (Philadelphia, 1990), 232-34. For a response to the many-gods objection see my "Pascal's Wager and the Many-Gods Objection," International Philosophical Quarterly 31, no. 3 (1991): 309-17.16. See David Hume, Dialogues Concerning Natural Religion, ed. N. Kemp Smith (1778; reprint, Indianapolis, 1947), 214, 218 (hereafter cited as "D").17. It should be noted that Philo's first point is interrupted by the second and is not completed until after the second is completed.18. I will assume that Philo speaks for Hume in this exchange with Cleanthes (D 219-27). Of the three points asserted by Philo in this exchange all three are asserted elsewhere by Hume. On the first point, see The Natural History of Religion (1757), secs. 9 and... (shrink)

Conventional rockets are not a suitable technology for interstellar missions. Chemical rockets require a very large weight of propellant, travel very slowly compared to light speed, and require significant energy to maintain operation over periods of years. For example, the 722 kg Voyager spacecraft required 13,600 kg of propellant to launch and would take about 80,000 years to reach the nearest star, Proxima Centauri, about 4.3 light years away. There have been various attempts at developing ideas on which one might (...) base a spacecraft that would permit interstellar travel, such as spacewarps. In this paper we consider another suggestion from science fiction and explore how the quantum vacuum might be utilized in the creation of a novel spacecraft. The spacecraft is based on the dynamic Casimir effect, in which electromagnetic radiation is emitted when an uncharged mirror is properly accelerated in vacuum. The radiative reaction produces a dissipative force on the mirror that tends to resist the acceleration of the mirror. This force can be used to accelerate a spacecraft attached to the mirror. We also show that, in principle, one could obtain the power to operate the accelerated mirror in such a spacecraft using energy extracted from the quantum vacuum using the standard Casimir effect with a parallel plate geometry. Unfortunately the method as currently conceived generates a miniscule thrust, and is no more practical than a spacewarp, yet it does provide an interesting demonstration of our current understanding of the physics of the quantized electromagnetic field in vacuum. (shrink)

Since its publication in 1965, Brian Barry's seminal work has occupied an important role in the revival of Anglo-American political philosophy. A number of ideas and terms in it have become part of the standard vocabulary, such as the distinction between "ideal-regarding" and "want-regarding" principles and the division of principles into aggregative and distributive. The book provided the first precise analysis of the concept of political values having trade-off relations and its analysis of the notion of the public interest has (...) also been significant. (shrink)

(No abstract is available for this citation).

My discussion of this theme falls into two parts. In the first part, starting from the assumption that we do in fact tend to respond favourably to the idea, vague though it may be, that “persons are to be respected, simply as persons”, I endeavour to clear my mind a little about our warrant for speaking in this way; and to do this is at the same time to clarify in some measure our understanding of what such language means. But (...) of course, since it is the language of practical principle, or precept, there can be no full understanding of its meaning without a grasp of its “working value”, of its significance as a clue to the proper directing and assessing of conduct. The second, and briefer, part of the discussion, accordingly, which is reserved for a subsequent article, is devoted to the question of the practical import of the principle of respect, the sort of guidance that it may provide in the actual business of life. (shrink)

There are many difficulties connected with the notion of punishment, but perhaps it is not disputed that it is at least a deliberate infliction of pain of one kind or another. Of course, that is not an adequate description of its nature, but so far as it goes it seems to be a true one.1 And the idea that it could be morally right deliberately tp inflict pain on another, unlike, for example, the idea that it is morally right to (...) tell the truth, is so manifestly intolerable unless we look beyond the infliction of pain itself that we are tempted to leap forward to the question, “What is the justification of such action?” before making quite explicit to ourselves what it is, over and above its being the deliberate infliction of pain, that constitutes the action punishment at all. The questions “Why hurt?” and “Why punish?” are confused with one another. No doubt some distinction between them is present vaguely in everyone's mind and the confusion may not be in fact serious: but anyhow it is a defect and should be remedied. (shrink)

Professor Strawson's paper is refreshing in content as well as refreshingly intemperate. It is salutary to be reminded that even the Type Identity Theory does not entail physicalism as that doctrine is usually understood (since c-fiber firings are not by definition purely physical). And it's fun to consider versions of panpsychism. I can see why Strawson finds his position hard to classify (p. 7), and I sympathize. In my title I have cast my own vote for '?-ism' on the grounds (...) that any familiar label would be either misleading or unwieldy. My main purpose here is to assess Strawson's case for panpsychism and then to offer some objections to panpsychism, but first I want to answer an interesting and serious charge he makes against me. (shrink)

Introduction, W G Runciman Social Evolution in Primates: The Role of Ecological Factors and Male Behaviour, Carel P van Schaik Determinants of Group Size in Primates: A General Model, R I M Dunbar Function and Intention in the Calls of Non-Human Primates, Dorothy L Cheney & Robert M Seyfarth Why Culture is Common, but Cultural Evolution is Rare, Robert Boyd & Peter J Richerson An Evolutionary and Chronological Framework for Human Social Behaviour, Robert A Foley Friendship and the Banker?s Paradox: (...) Other Pathways to the Evolution of Adaptations for Altruism, John Tooby & Leda Cosmides The Early Prehistory of Human Social Behaviour: Issues of Archaeological Inference and Cognitive Evolution, Steven Mithen The Emergence of Biologically Modern Populations in Europe: A Social and Cognitive ?Revolution??, Paul Mellars Responses to Environmental Novelty: Changes in Men?s Marriage Strategies in a Rural Kenyan Community, Monique Borgerhoff Mulder Genetic Language Impairment: Unruly Grammars, M Gopnik, J Dalalakis, S E Fukuda, S Fukuda & E Kehayia The Emergence of Cultures among Wild Chimpanzees, Christophe Boesch Terrestriality, Bipedalism and the Origin of Language, Leslie C Aiello Conclusions, John Maynard Smith. (shrink)

In Part I of this discussion I considered the nature and validity of the principle of respect for persons as distinguished from its practical import and application. Before I proceed to that second topic let me draw together in summary fashion the main points of the view I have put forward.