We make a brief review of the Kramers escape rate theory for the probabilistic motion of a particle in a potential well U(x), and under the influence of classical fluctuation forces. The Kramers theory is extended in order to take into account the action of the thermal and zero-point random electromagnetic fields on a charged particle. The result is physically relevant because we get a non-null escape rate over the potential barrier at low temperatures (T → 0). It is found (...) that, even if the mean energy is much smaller than the barrier height, the classical particle can escape from the potential well due to the action of the zero-point fluctuating fields. These stochastic effects can be used to give a classical interpretation to some quantum tunneling phenomena. Relevant experimental data are used to illustrate the theoretical results. (shrink)

We consider the simple case of a nonrelativistic charged harmonic oscillator in one dimension, to investigate how to take into account the radiation reaction and vacuum fluctuation forces within the Schrödinger equation. The effects of both zero-point and thermal classical electromagnetic vacuum fields, characteristic of stochastic electrodynamics, are separately considered. Our study confirms that the zero-point electromagnetic fluctuations are dynamically related to the momentum operator p=−i ℏ ∂/∂ x used in the Schrödinger equation.

Book reviewed in this article: Not In Our Genes: Biology, Ideology, and Human Nature. By R. C. Lewontin, Steven Rose, and Leon J. Kamin.

‘Mysticism means to isolate the eternal from the originated.’ This is not my definition of the word ‘mysticism’ but that of the founder of the ‘orthodox’ school of Muslim mysticism, Al-Junayd of Baghdad who flourished in the ninth century a.d . In actual fact it is not a definition of mysticism at all but of the Arabic word tawḥīd which means primarily ‘the affirmation of unity’; and that surely is an essential ingredient of any form of mysticism: it is the (...) affirmation through personal experience of unity either absolutely or in some qualified sense. (shrink)

As everyone knows, since the end of the Second World War there has been a sensational revival of interest in the non-Christian religions particularly in the United States and in this country. The revival has taken two forms, the one popular, the other academic. The first of these has turned almost exclusively to Hindu and Buddhist mysticism and can be seen as an energetic reaction against the dogmatic and until very recently rigid structure of institutionalised Christianity and a search for (...) a lived experience of the freedom of the spirit which is held to be the true content of mysticism, obscured in Christianity by the basic dogma of a transcendent God, the ‘wholly Other’ of Rudolf Otto and his numerous followers, but wholly untrammelled by any such concept in the higher reaches of Vedanta and Buddhism, particularly in its Zen manifestation. On the academic side the picture is less clear. There is, of course, the claim that the study of religion, like any other academic study, must be subjected to and controlled by the same principles of ‘scientific’ objectivity to which the other ‘arts’ subjects have been subjected, to their own undoing. But even here there would seem to be a bias in favour of the religions of India and the Far East as against Islam, largely, one supposes, in response to popular demand. (shrink)

The problem that confronts us when we try to compare the structure of discourse and explanation in different domains of knowledge is that no one is an insider in more than one field, and insider information is essential. An observer who is not immersed in the practice of a particular scholarship and who wants to understand it is at the mercy of the practitioners. Yet those practitioners are themselves mystified by a largely unexamined communal myth of how scholarship is carried (...) on. R. G. Collingwood, although primarily a philosopher, was immersed in the community of historians and understood how history is done, so that he has had an immense influence on our ideas about historiography. Every historian knows The Idea of History.1 He was also a metaphysician, yet his influence on scientists’ understanding of nature, and of science, has been nil, and it is a rare scientist indeed who has ever heard of Collingwood or read The Idea of Nature.2 Collingwood’s views of the structure of science had to be constructed in large part from the elaborate fictions created by scientists and by an earlier generation of philosophers and historians of science who participated in the Baconian myth of the hypothetical-deductive scheme. 1. See R. G. Collingwood, The Idea of History .2. See Collingwood, The Idea of Nature . R. C. Lewontin is Alexander Agassiz Professor at Harvard University. He is an experimental and theoretical evolutionary geneticist who has also worked extensively on epistemological issues in biology. He is the author of The Genetic Basis of Evolutionary Change and, with Richard Levins, of The Dialectical Biologist . His current research concerns the nature of genetic variation among individuals within species. (shrink)

Papers presented at the National Seminar on "The Challenges of Postmodernism", hosted by the Department of Philosophy, University of Hyderabad during 28-30 March 2006.

As an immediate reply, meanwhile, I should like to make a remark or two about what is perhaps the central issue raised in the foregoing Comment. This is whether Price's dispositional reduction, or anyone's dispositional reduction can adequately render the act of thinking. Alternatively, the question could, I think, be stated in more presently-favoured language. One could ask whether statements about universals, thoughts, concepts, or ideas can be logically deduced from dispositional statements not containing these "mentalistic" terms. If one is (...) inclined to prefer this more lengthy formulation one may then take this to be my meaning; whenever "dispositional solution" or "dispositional reduction" is mentioned one may translate it into this longer form. (shrink)

Torporley's ‘Congestor analyticus’, completed in 1627 in the library of the Earl of Northumberland at Petworth, was seen by Rigaud in the 1830s among the mathematical manuscript collection of the Earl of Macclesfield. Torporley's additional copy of the introductory part, preserved at Sion College, has been used for the present report. Torporley's prime objective was the presentation of some of Harriot's work. His first example concerns a classical problem in number theory. The complete solution, by an inductive process based on (...) tables of differences, is given in a few folios of the British Library collection of Harriot manuscripts. Torporley's transcription and commentary contrast forcibly today with the immediate illuminating impact of Harriot's original. (shrink)