Solid State Physics

The universality of critical phenomena is best explained by appeal to the Renormalisation Group (RG). Batterman and Morrison, among others, have claimed that this explanation is irreducible. I argue that the RG account is reducible, but that the higher-level explanation ought not to be eliminated. I demonstrate that the key assumption on which the explanation relies – the scale invariance of critical systems – can be explained in lower-level terms; however, we should not replace the RG explanation with a bottom-up (...) account, rather we should acknowledge that the explanation appeals to dependencies which may be traced down to lower levels. (shrink)

Recent discussions of emergence in physics have focussed on the use of limiting relations, and often particularly on singular or asymptotic limits. We discuss a putative example of emergence that does not fit into this narrative: the case of phonons. These quasi-particles have some claim to be emergent, not least because the way in which they relate to the underlying crystal is almost precisely analogous to the way in which quantum particles relate to the underlying quantum field theory. But there (...) is no need to take a limit when moving from a crystal lattice based description to the phonon description. Not only does this demonstrate that we can have emergence without limits, but also provides a way of understanding cases that do involve limits. (shrink)

Solid state physics, the study of the physical properties of solid matter, was the most populous subfield of Cold War American physics. Despite prolific contributions to consumer and medical technology, such as the transistor and magnetic resonance imaging, it garnered less professional prestige and public attention than nuclear and particle physics. Solid State Insurrection argues that solid state physics was essential to securing the vast social, political, and financial capital Cold War physics enjoyed in the twentieth century. Solid state’s technological (...) bent, and its challenge to the “pure science” ideal many physicists cherished, helped physics as a whole respond more readily to Cold War social, political, and economic pressures. Its research kept physics economically and technologically relevant, sustaining its cultural standing and policy influence long after the sheen of the Manhattan Project had faded. (shrink)

In this brief note, we focus attention on a possible implementation of a basic hysteretic pattern (the Preisach one), suitably generalized, into a formal model of unconscious-conscious interconnection and based on representation of mental entities by m-adic numbers.

How does a predecessor theory relate to its successor? According to Heinz Post’s General Correspondence Principle, the successor theory has to account for the em- pirical success of its predecessor. After a critical discussion of this principle, I outline and discuss various kinds of correspondence relations that hold between successive scientific theories. I then look in some detail at a case study from contemporary physics: the various proposals for a theory of high-temperature superconductivity. The aim of this case study is (...) to understand better the prospects and the place of a methodological principle such as the Generalized Correspondence Principle. Generalizing from the case study, I will then argue that some such principle has to be considered, at best, as one tool that might guide scientists in their theoriz- ing. Finally I present a tentative account of why principles such as the Generalized Correspondence Principle work so often and why there is so much continuity in scientific theorizing. (shrink)

This article argues that phenomenological treatment of physical problems is more powerful than fundamental treatment. Developments in the field of superconductivity present us with a clear example of such superiority. The BCS (Bardeen, Cooper and Schrieffer) was accepted as the fundamental theory of superconductivity for a long time. Nevertheless, Landau and Ginzburg phenomenological model has so far proven to be a more fruitful theoretical representation to understand and to predict the features of superconductivity and superconductive materials.

The present paper examines the role of exact results in the theory of many‐body physics, and specifically the example of the Mermin‐Wagner theorem, a rigorous result concerning the absence of phase transitions in low‐dimensional systems. While the theorem has been shown to hold for a wide range of many‐body models, it is frequently ‘violated’ by results derived from the same models using numerical techniques. This raises the question of how scientists regulate their theoretical commitments in such cases, given that the (...) models, too, are often described as approximations to the underlying ‘full’ many‐body problem. (shrink)

Building upon Nancy Cartwright's discussion of models in How the Laws of Physics Lie, this paper addresses solid state research in transition metal oxides. Historical analysis reveals that in this domain models function both as the culmination of phenomenology and the commencement of theoretical explanation. Those solid state chemists who concentrate on the description of phenomena pertinent to specific elements or compounds assess models according to different standards than those who seek explanation grounded in approximate applications of the Schroedinger equation. (...) Accurate accounts of scientific debate in this field must include both perspectives. (shrink)

In June 1930 the Department of Scientific and Industrial Research of the British Government awarded a modest research grant to J. E. Lennard-Jones, Professor of Theoretical Physics at the University of Bristol, in response to a proposal submitted under the title of ‘A theoretical investigation of the physical properties of the solid state of matter’. This initiative marked the first notable recognition by public funding bodies in Great Britain of the potential contribution to be made by the new theoretical ideas (...) in physics to a deeper understanding of the properties of industrially important materials, particularly metals and their alloys. The possible technological relevance of such a study was, indeed, a central factor in the decision to support it. The research arising out of this initial award provided the impetus for the first stage of Bristol theoretical research on the solid state of matter, an enterprise initially associated with the name of Lennard-Jones, and later with Nevili Mott who succeeded him as Professor of Theoretical Physics in 1933. (shrink)

Alternate View Column AV-110 Keywords: linear electron positron collider e+e- high energy particle physics accelerator tunnel USA Japan Germany Published in the February-2002 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 8/4/2001 and is copyrighted ©2001 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

Recent case studies have revealed that purely formal analogies have been successfully used as a heuristic in physics. This is at odds with most general philosophical accounts of analogies, which require analogies to be physical in order to be justifiably used. The main goal of this paper is to supply a philosophical account that justifies the use of purely formal analogies in physics. Using Bartha’s (2010) articulation model as a starting point, I offer precise definitions of formal and physical analogies (...) and propose a new submodel of analogical reasoning that accounts for the successful use of purely formal analogies in the development of renormalization group methods for use in particle physics in the early 1970’s (Fraser 2020). Two distinctive features of this new applied mathematics submodel for analogical reasoning are that the conclusion of the argument from analogy includes both an entire model (and not only a hypothesis or a prediction) and the construction procedure for this model. A third important difference from arguments from physical analogy is that only the prima facie plausibility of the conclusion is established, and not stronger types of plausibility associated with confirmation. The use of purely formal analogies is justified because they are suited to supporting conclusions of this sort. Formulating a general philosophical account of analogies that covers purely formal analogies also serves two additional purposes: (1) to highlight the features of this case that are novel in the context of examples of analogies traditionally considered by philosophers and (2) to establish that physicists should not automatically dismiss purely formal analogies when evaluating heuristics for the development of new models. (shrink)

During the 20th century there were a couple of scientists who announced the observation of exceptional heat during the electrolysis of water with the help of Palladium electrodes. In spite of the opinion of the community of nuclear physicists that low energy generated nuclear fusion is a hoax there is a lot of research to understand and create the observed emission of exceptional electromagnetic radiation. This paper explains with the help of the concept of quantized space the simple mechanism that (...) is responsible for the decrease of the Coulomb force of Hydrogen nuclei, established by Martin Fleischmann and Stanley Pons. (shrink)

In this article, the author shows the role and importance of the process of solving physical problems in the study of natural phenomena and laws, understanding the physical picture of the world. Also, in order to increase interest in physics, to jointly solve existing physical problems, methods of organizing master classes on modern forms of education were developed, the history of development, their role, goals and objectives in higher education and recommendations on the chosen topic were revealed. It is noted (...) that master classes in physics, which were organized in the past centuries, subsequently led to great discoveries. It was shown that the organization of master classes allows future professionals to work together, learn non-standard thinking, develop creativity and practice their thinking. (shrink)