Studies in History and Philosophy of Modern Physics最新文献

{"title":"Bohm's theory of quantum mechanics and the notion of classicality","authors":"Marij van Strien","doi":"10.1016/j.shpsb.2020.04.005","DOIUrl":"10.1016/j.shpsb.2020.04.005","url":null,"abstract":"<div><p>When David Bohm published his alternative theory of quantum mechanics in 1952, it was not received well; a recurring criticism was that it formed a reactionary attempt to return to classical physics. In response, Bohm emphasized the progressiveness of his approach, and even turned the accusation of classicality around by arguing that he wanted to move beyond classical elements still inherent in orthodox quantum mechanics. In later years, he moved more and more towards speculative and mystical directions.</p><p>This paper aims to explain this discrepancy between the ways in which Bohm's work on quantum mechanics has been received and the way in which Bohm himself presented it. I reject the idea that Bohm's early work can be described as mechanist, determinist, and realist, in contrast to his later writings, and argue that there is in fact a strong continuity between his work on quantum mechanics from the early 1950s and his later, more speculative writings. In particular, I argue that Bohm was never strongly committed to determinism and was a realist in some ways but not in others. A closer look at Bohm's philosophical commitments highlights the ways in which his theory of quantum mechanics is non-classical and does not offer a way to avoid all ‘quantum weirdness’.</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 72-86"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.04.005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47826042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The concept ‘indistinguishable’","authors":"Simon Saunders","doi":"10.1016/j.shpsb.2020.02.003","DOIUrl":"https://doi.org/10.1016/j.shpsb.2020.02.003","url":null,"abstract":"<div><p>The concept of indistinguishable particles in quantum theory is fundamental to questions of ontology. All ordinary matter is made of electrons, protons, neutrons, and photons and they are all indistinguishable particles. Yet the concept itself has proved elusive, in part because of the interpretational difficulties that afflict quantum theory quite generally, and in part because the concept was so central to the discovery of the quantum itself, by Planck in 1900; it came encumbered with revolution.</p><p>I offer a deflationary reading of the concept ‘indistinguishable’ that is identical to Gibbs' concept ‘generic phase’, save that it is defined for state spaces with only <em>finitely</em>-many states of bounded volume and energy (finitely-many orthogonal states, in quantum mechanics). That, and that alone, makes for the difference between the quantum and Gibbsean concepts of indistinguishability.</p><p>This claim is heretical on several counts, but here we consider only the content of the claim itself, and its bearing on the early history of quantum theory rather than in relation to contemporary debates about particle indistinguishability and permutation symmetry. It powerfully illuminates that history.</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 37-59"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.02.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91983124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"‘Like thermodynamics before Boltzmann.’ On the emergence of Einstein's distinction between constructive and principle theories","authors":"Marco Giovanelli","doi":"10.1016/j.shpsb.2020.02.005","DOIUrl":"10.1016/j.shpsb.2020.02.005","url":null,"abstract":"<div><p>In a 1919 article for the <em>Times</em><span> of London, Einstein declared the relativity theory<span> to be a ‘principle theory’, like thermodynamics, rather than a ‘constructive theory’, like the kinetic theory<span> of gases. The present paper attempts to trace back the prehistory of this famous distinction. It provides a systematic overview of Einstein's repeated use of the relativity theory/thermodynamics analysis after 1905 and inserts it into its historical settings, the early reception of relativity against the background of </span></span></span><em>fin de siècle</em><span> electron theories. Einstein initially used the relativity theory/thermodynamics comparison to address a specific objection. In his 1905 relativity paper he had determined the velocity-dependence of the electron's mass by adapting Newton's particle dynamics to the relativity principle. However, according to many, this result was not admissible without making some assumption about the structure of the electron. Einstein replied that the relativity theory is similar to thermodynamics. Unlike the usual physical theories, it does not directly try to construct models of specific physical systems; it provides empirically motivated and mathematically formulated criteria for the acceptability of such theories. New theories can be obtained by modifying existing theories valid in limiting case so that they comply with such criteria. Einstein progressively transformed this line of the defense into a positive heuristics. Instead of directly searching for new theories, it is often more effective to search for conditions that constraint the number of possible theories. The constructive/principle theories opposition should be considered not only as abstract classification of theories, but also as Einstein's attempt to formulate a sort of ‘logic of discovery’. The paper argues that most of Einstein's scientific successes were obtained by following the principle strategy. Most of his failures happened when he was forced to fall back to the constructive strategy.</span></p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 118-157"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.02.005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44238714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spacetime as a quantum error-correcting code?","authors":"Jonathan Bain","doi":"10.1016/j.shpsb.2020.04.002","DOIUrl":"10.1016/j.shpsb.2020.04.002","url":null,"abstract":"<div><p>This essay considers an interpretation of the AdS/CFT correspondence under which the bulk and the boundary emerge from a more fundamental discrete system that realizes the structure of an erasure-protection quantum error-correcting code (QECC). I consider the extent to which this view underwrites the claim that spacetime is a QECC (as some authors have suggested), and how it fits into recent schemes of realist interpretations of dualities.</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 26-36"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.04.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45033988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"“— It would be possible to do a lengthy dialectical number on this;”","authors":"Wayne C. Myrvold","doi":"10.1016/j.shpsb.2019.12.001","DOIUrl":"10.1016/j.shpsb.2019.12.001","url":null,"abstract":"<div><p>Philosophers have, it seems, been beguiled by contingencies of the evolution of scientific language. These contingencies can obscure the nature of theoretical shifts. Retention of a term can obscure a radical theoretical shift, and abandonment of a term can obscure continuity of theory. In this paper, I consider the cases of caloric and the luminiferous ether, both of which are often taken to be unproblematic cases of theoretical entities abandoned by subsequent theories. I invite the reader to consider what we might now be saying were those terms retained, and argue that this sheds light on the nature of the theoretical shifts involved..</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 209-219"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2019.12.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43240250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Loop quantum ontology: Spacetime and spin-networks","authors":"Joshua Norton","doi":"10.1016/j.shpsb.2020.04.001","DOIUrl":"10.1016/j.shpsb.2020.04.001","url":null,"abstract":"<div><p>It is standardly claimed in loop quantum gravity<span> (LQG) that spacetime both disappears, fundamentally, and emerges from spin-networks in the low energy regime. In this paper, I critically explore these claims and develop a variety of substantival and relational interpretations of LQG for which these claims are false. According to most of the interpretations I consider, including the “received interpretation”, it is in fact false that spacetime emerges from spin-networks. In the process of supporting these claims, I also explain why spacetime is thought to be missing from the theory's fundamental ontology and demonstrate how this conclusion depends on our interpretation of the theory. In fact, I will argue that for a variety of interpretations spacetime survives quantization just as the electromagnetic field<span> survives quantization. The upshot of the following analysis is a much needed clarification of the ontology of LQG and how it relates, or fails to relate, to the spacetime of general relativity.</span></span></p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 14-25"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.04.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45105080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Some reflections on the structure of cosmological knowledge","authors":"Chris Smeenk","doi":"10.1016/j.shpsb.2020.05.004","DOIUrl":"10.1016/j.shpsb.2020.05.004","url":null,"abstract":"<div><p><span><span><span>Stein has characterized one of the central problems in accounting for our knowledge in physics as that of getting the laboratory, or observatory, inside the theory — that is, of understanding how the mathematical structures of fundamental physical theories have empirical content. He has argued that physicists respond to this problem by giving schematic representations of observers and experiments. In addition, Stein emphasizes the importance of regarding knowledge as an enterprise, with current theories providing guidance for future inquiry. I will explore some ramifications of this way of thinking about the structure of scientific theories for contemporary cosmology. One goal of </span>observational cosmology<span> is to measure the six basic parameters appearing in the standard model of cosmology. These parameters are well-defined if the universe is suitably approximated at some scale by a perturbed FLRW model. The enormous extrapolations involved in the standard model are often justified by the consistent determination of these parameters via a variety of methods. Here I will consider two recent debates regarding this approach to cosmology, inspired by Stein's work. The first debate regards the impact of different ways of characterizing the propagation of light through a cosmological spacetime on the determination of </span></span>cosmological parameters (such as </span><span><math><mrow><msub><mi>H</mi><mn>0</mn></msub></mrow></math></span>). The second regards how the highly symmetric FLRW models relate to describing the real universe, at small scales where it is very lumpy.</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 220-231"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.05.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46765141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective field theories as a novel probe of fine-tuning of cosmic inflation","authors":"Feraz Azhar","doi":"10.1016/j.shpsb.2020.05.001","DOIUrl":"10.1016/j.shpsb.2020.05.001","url":null,"abstract":"<div><p><span>The leading account of several salient observable features of our universe today is provided by the theory of cosmic inflation. But an important and thus far intractable question is whether inflation is generic, or whether it is finely tuned—requiring very precisely specified initial conditions. In this paper I argue that a recent, model-independent characterization of inflation—that treats inflation as an </span>effective field theory (EFT)—promises to address this question in a thoroughly modern and significantly more comprehensive way than in the existing literature.</p><p>To motivate and provide context for this claim, I distill three core problems with the theory of inflation, which I dub the <em>permissiveness problem</em>, the <em>initial conditions problem</em>, and the <em>multiverse problem</em><span><span>. I argue that the initial conditions problem lies within the scope of EFTs of inflation as they are currently conceived, whereas the other two problems remain largely intractable: their solution must await a more complete description of the very early universe. I highlight recent work that addresses the initial conditions problem within the context of a </span>dynamical systems analysis of a specific (state-of-the-art) EFT of inflation, and conclude with a roadmap for how such work might be extended to realize the promise claimed above.</span></p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 87-100"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.05.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75429580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MOND vs. dark matter in light of historical parallels","authors":"Mordehai Milgrom","doi":"10.1016/j.shpsb.2020.02.004","DOIUrl":"10.1016/j.shpsb.2020.02.004","url":null,"abstract":"<div><p><span>MOND is a paradigm that contends to account for the mass discrepancies in the Universe without invoking ‘dark’ components, such as ‘dark matter’ and ‘dark energy’. It does so by supplanting Newtonian dynamics and General Relativity, departing from them at very low accelerations. Having in mind readers who are historians and philosophers of science, as well as physicists and astronomers, I describe in this review the main aspects of MOND – its statement, its basic tenets, its main predictions, and the tests of these predictions – contrasting it with the dark-matter paradigm. I then discuss possible wider ramifications of MOND, for example the potential significance of the MOND constant, </span><span><math><mrow><msub><mi>a</mi><mn>0</mn></msub></mrow></math></span><span>, with possible implications for the roots of MOND in cosmology. Along the way I point to parallels with several historical instances of nascent paradigms. In particular, with the emergence of the Copernican world picture, that of quantum physics, and that of relativity, as regards their initial advent, their development, their schematic structure, and their ramifications. For example, the interplay between theories and their corollary laws, and the centrality of a new constant with converging values as deduced from seemingly unrelated manifestations of these laws. I demonstrate how MOND has already unearthed a number of unsuspected laws of galactic dynamics (to which, indeed, </span><span><math><mrow><msub><mi>a</mi><mn>0</mn></msub></mrow></math></span> is central) predicting them a priori, and leading to their subsequent verification. I parallel the struggle of the new with the old paradigms, and the appearance of hybrid paradigms at such times of struggle. I also try to identify in the history of those established paradigms a stage that can be likened to that of MOND today.</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"71 ","pages":"Pages 170-195"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.02.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80932357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An unpublished debate brought to light: Karl Popper's enterprise against the logic of quantum mechanics","authors":"Flavio Del Santo","doi":"10.1016/j.shpsb.2020.03.001","DOIUrl":"10.1016/j.shpsb.2020.03.001","url":null,"abstract":"<div><p>Karl Popper published, in 1968, a paper that allegedly found a flaw in a very influential article of Birkhoff and von Neumann, which pioneered the field of “quantum logic”. Nevertheless, nobody rebutted Popper's criticism in print for several years. This has been called in the historiographical literature an “unsolved historical issue”. Although Popper's proposal turned out to be merely based on misinterpretations and was eventually abandoned by the author himself, this paper aims at providing a resolution to such historical open issues. I show that (i) Popper's paper was just the tip of an iceberg of a much vaster campaign conducted by Popper against quantum logic (which encompassed several more unpublished papers that I retrieved); and (ii) that Popper's paper stimulated a heated debate that remained however confined within private correspondence.</p></div>","PeriodicalId":54442,"journal":{"name":"Studies in History and Philosophy of Modern Physics","volume":"70 ","pages":"Pages 65-78"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.shpsb.2020.03.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133139819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}