Philosophy of Physical Science

Jag tror att det är ett misstag att kräva av humanvetenskaperna (d.v.s. humaniora, samhälls- och beteendevetenskaperna) att de imiterar naturvetenskapernas forskningsmetodik. Humanvetenskaperna studerar meningsfulla fenomen vilkas natur är på ett grundläggande sätt annorlunda än de blott fysiska fenomen som naturvetenskapen studerar. Den största skillnaden är att meningsfulla fenomen inte uppenbarligen är lagbundna på samma sätt som fysiska fenomen och uppvisar därför inte samma regelbundenhet och förutsägbarhet som fysiska fenomen. För att studera meningsfulla fenomen krävs därför andra forskningsmetoder. Trots att humanvetenskaperna (...) studerar fenomen som inte är lagbundna och är på ett visst sätt subjektiva, så vill jag mena att de studerar objektivt verkliga fenomen och kan få giltig kunskap om dem. Att subjektiva fenomen också kan vara objektivt verkliga kan låta märkligt för vissa läsare, varför jag rundar av med en diskussion om vad det egentligen innebär för något att vara objektivt verkligt. Enligt den definition jag föreslår så framstår att meningsfulla fenomen, också de som kallas ”sociala konstruktioner”, kan förstås som objektivt verkliga företeelser trots att de på ett betydelsefullt sätt också är subjektiva. (shrink)

This paper investigates dynamical relaxation to quantum equilibrium in the stochastic de Broglie–Bohm–Bell formulation of quantum mechanics. The time-dependent probability distributions are computed as in a Markov process with slowly varying transition matrices. Numerical simulations, supported by exact results for the large-time behavior of sequences of (slowly varying) transition matrices, confirm previous findings that indicate that de Broglie–Bohm–Bell dynamics allows an arbitrary initial probability distribution to relax to quantum equilibrium; i.e., there is no need to make the ad-hoc assumption that (...) the initial distribution of particle locations has to be identical to the initial probability distribution prescribed by the system’s initial wave function. The results presented in this paper moreover suggest that the intrinsically stochastic nature of Bell’s formulation, which is arguable most naturally formulated on an underlying discrete space-time, is sufficient to ensure dynamical relaxation to quantum equilibrium for a large class of quantum systems without the need to introduce coarse-graining or any other modification in the formulation. (shrink)

This book is a record of my dialogues with Stephen Hawking, his graduate assistants and his nurses during a four city public lecture tour I organized for Hawking, including Portland, Eugene, Seattle, Vancouver, BC. We discussed 20th century science and philosophy of science. Since I was often the one being questioned, much of the contents reflect my PhD research at the University of London. My focus was on understanding the limits of science, as represented by quantum theory and relativity. My (...) mentors had been Paul Feyerabend and Imre Lakatos, and I was strongly influenced by Karl Popper and Thomas Kuhn. In one in depth presentation to Hawking I suggested that Newtonian space-time and Maxwellian space-time were complementary, were defined by complementary symmetry principles. I had opportunity to present the same arguments to Kip Thorne and Freeman Dyson. Hawking simply remarked that I 'may be right'. Thorne confirmed that practitioners of General Relativity use both depending on the problem at hand. Dyson was emphatic – "Yes. Definitely. Absolutely.". (shrink)

The relational interpretation of quantum mechanics (RQM) has received a growing interest since its first formulation in 1996. Usually presented as an interpretational layer over the usual quantum mechanics formalism, it appears as a philosophical perspective without proper mathematical counterparts. This state of affairs has direct consequences on the scientific debate on RQM which still suffers from misunderstandings and imprecise statements. In an attempt to clarify those debates, the present paper proposes a radical reformulation of the mathematical framework of quantum (...) mechanics which is relational from the start: fact-nets. The core idea is that all statements about the world, facts, are binary entities involving two systems that can be symmetrically thought of as observed and observer. We initiate a study of the fact-nets formalism and outline how it can shed new relational light on some familiar quantum features. (shrink)

The detection of the number of extra–compact dimensions contained in some gravitational models is analyzed resorting to the discontinuity of the specific heat at the critical temperature of a Bose–Einstein condensate. It is shown that the function relating the number of particles and this discontinuity defines a segment of a straight line whose slope depends upon the number of extra–compact dimensions. The experimental feasibility of the proposal is also considered.

While vitally critical, the relationship between conscious system and the central nervous system (CNS) is least interested to the scientific community, and often regarded as abstractly conceptual in philosophy or religion. We argue that the existence of consciousness system is parallel to, and independent of, CNS. First and foremost, all sciences are based on logic, not any existing theories, so does neuroscience. So, neuroscience shall start from some theory-independent logic, not some neural or molecular hypotheses, or count on modern physics (...) which is neither completed nor physically deep enough. It shall hypothesize the brain has a CNS (central nervous system) independent consciousness system. Then, we have explained why this hypothesis is theory-independent from the view of methodology, philosophy and physics; what a strong experimental logic this hypothesis can produce; how the logic can measure consciousness. In short, sciences are based on logic, and it is serious for neuroscience to hypothesize there is a CNS-independent consciousness system. -/- . (shrink)

David Bohm published his “Suggested Interpretation of Quantum Theory in Terms of Hidden Variables” some twenty five years after Louis de Broglie first presented his similar Pilot Wave theory of quantum mechanics. In the following 30 years what became known as the de Broglie–Bohm approach to quantum theory was to a large extent ignored within the physics community. Even David Bohm himself became somewhat disillusioned with the lack of impact of his interpretation of quantum theory and he directed his interest (...) elsewhere. But some 27 years after Bohm had published his interpretation of quantum theory, interest was rekindled in part by new, detailed calculations that demonstrated clearly and graphically, exactly how his interpretation explained quantum phenomena in terms of well defined individual particle trajectories. These computations encompassed two-slit interference, quantum tunnelling, neutron interferometry, Wheeler’s delayed choice experiment, orbital and intrinsic angular momentum, quantum measurement and Einstein–Podolsky–Rosen nonlocal correlations for orbital angular momentum, intrinsic angular momentum and correlated particle interferometry. Since then, the acceptance of the validity of de Broglie–Bohm theory has steadily grown, as has the interest in the consequences of the approach. For my contribution to the current celebratory volume I was asked to provide a personal review specifically of this novel work within its historical context of the last quarter of the twentieth century. (shrink)

The book is an in-depth study of naturalized epistemology in its two versions - physicalist and evolutionist. At the same time, it is the sole existing detailed discussion of evolutionary epistemology (as far as Polish and foreign literature is concerned). Malinowska asks about the ontological, methodological, and epistemological foundations of the positions she discusses. She argues (referring not only to philosophical discussions but also those in the field of neuroscience or genetics) that bio-cultural constructivism (a research program pursued by cultural (...) neuroscience, among other fields) is a contemporary, interdisciplinary continuation of the evolutionary epistemology program. The book’s accessible language, clear structure and multidisciplinary nature make it an exciting read for a wide audience. (shrink)

The ontological models framework distinguishes _ψ_-ontic from _ ψ_-epistemic wave-functions. It is, in general, quite straightforward to categorize the wave-function of a certain quantum theory. Nevertheless, there has been a debate about the ontological status of the wave-function in the statistical interpretation of quantum mechanics: is it _ψ_-epistemic and incomplete or _ ψ_-ontic and complete? I will argue that the wave-function in this interpretation is best regarded as _ψ_-ontic _and incomplete_.

The obscure and punctuated history of symmetry is compared with the history of the celebrated and exalting notion of infinitesimal; some considerations about them are derived. A long list of odd and hidden events concerning symmetry in theoretical physics is offered. The last event is the discovery of the nature of the same word “symmetry” which pertains to non-classical logic, and it is linked to the principle of sufficient reason. A comparison of the roles played by the two mathematical techniques (...) within a classical physical theory is performed. It leads to recognize the different roles played by the two mathematical tools as a manifestation of an incommensurability phenomenon caused by two foundational dichotomies. (shrink)

Expert judgment can be seen throughout climate science and even more prominently when discussing climate tipping points. To provide an accurate characterization of expert judgment we begin by evaluating the existing literature on expertise as it relates to climate science as a whole, before then focusing the literature review on the role of expert judgment in the unique context of climate tipping points. From this we turn our attention to the structured expert elicitation protocols specifically developed for producing expert judgments (...) about tipping points. We highlight that expert elicitation is not only used for the quantification of uncertainty in this context, but also for the very identification and characterization of tipping points and their interactions, making expert judgment in itself a genuine scientific output. The central role of expert judgment in this domain raises several epistemic issues that require careful attention. Among other topics, we discuss the relationship between expert judgment and modeling, as well as the nonepistemic values that are involved in the production of expert judgments, highlighting how the elicitation protocols can be used to manage these values. In the perspective of climate change, clarifying the epistemic foundations of expert judgment in this context can help to navigate the epistemic situation between self-defeating alarmism and blind dismissal, thus contributing to a better understanding of the challenges related to climate (and Earth system) tipping points. (shrink)

Structures without time and dynamics are considered. The principle is proposed how to build space-time in a structure without time and dynamics. It is found what can be objects in such a space-time, and what can be an interaction between such objects.Within the framework of the considered class of structures, answers were found to the following problems of philosophy and physics: the nature of consciousness and the connection between the body and consciousness (mind-body problem), nature of time, anthropic principle and (...) the problem of fine-tuning the universe, the effectiveness of mathematics in describing physical phenomena, limits of knowledge.The considered class of structures makes it possible to find answers to questions that cannot be answered for our Universe. This shows the fundamental possibility of finding answers to these questions for our Universe as well. (shrink)

Mach repudiated Newton’s argument for absolute time. He denied there is such a thing as time itself that exists independently of any external change. In doing so, Mach failed to appreciate Newton’s scientific practice. Absolute time is intrinsically related to Newton’s laws of motion and the method of fluxions. Commentators have noted similarities between Mach’s rejection of Newtonian time and his rejection of the independent existence of atoms. In this article, it shall be argued that the juxtaposition of absolute time (...) and the atomic theory is unsound. Mach had good reasons to question the existence of substantial time, and he went on to provide an alternative, ontologically relational account. Whereas his dismissal of atoms can be seen as a questionable form of “phenomenalism” or “positivism,” this is not the case regarding his position on time. (shrink)

We reconstruct Kuhn’s philosophy of measurement and data paying special attention to what he calls the “fifth law of thermodynamics”. According to this "law," there will always be discrepancies between experimental results and scientists’ prior expectations. The history of experiments to determine the values of the fundamental constants offers a striking illustration of Kuhn’s fifth law of thermodynamics, with no experiment giving quite the expected result. We highlight the synergy between Kuhn’s view and the systematic project of iteratively determining the (...) value of physical constants, initiated by spectroscopist Raymond Birge, that was ongoing when Kuhn joined Berkeley in 1956. Our analysis sheds light on various underappreciated aspects of Kuhn’s thought, especially his notion of progress as improvement in measurement accuracy. (shrink)

This book is inspired by a German theoretical physicist, Sabine Hossenfelder’s publication: “Lost in Mathematics”. Her book seems to question highly mathematical and a lot of abstraction in the development of physics and cosmology studies nowadays. There is clear tendency that in recent decades, the physics science has been predominated by such an advanced mathematics, which at times sounding more like acrobatics approach to a reality. Through books by senior mathematical-physicists like Unzicker and Peter Woit, we know that the answer (...) of TOE is not in superstring theories or other variations of such 26 dimensional bosonic string theory, of which none of those theories survived experimental test, but perhaps in low dimensional physics. As Alexander Unzicker suggests, perhaps it is more advisable to consider rotation in 3D space (known as SO3), or a kind of superfluid vortices version of gravitation theory. We can also reconsider proposition by the late Prof F. Winterberg (formerly professor at Univ. Nevada, Reno), that it is most likely that superfluid phonon roton theory in 3D can replace the entire superstring theories. While we don’t explore yet implications of his model to particle physics, we discuss here some published papers at several journals in the past few years. (shrink)

Heinrich Hertz dedicated the last four years of his life to a systematic reformulation of mechanics. One of the main issues that troubled Hertz in the customary formulation of mechanics was a "logical obscurity" in the notion of force. However, it is unclear what this logical obscurity was, hence it is unclear how Hertz took himself to have avoided it. -/- In this paper, I argue that a subtle ambiguity in Newton's original laws of motion lay at the basis of (...) Hertz's concerns; an ambiguity which led to the development of two slightly different notions of force. I then show how Hertz avoided this ambiguity by deriving a unitary notion of force, thus dispelling the obscurity that lurked in the customary representation of mechanics. (shrink)

It is shown that, in some non-QCD theories, there are effects shared by QCD: (i) in SU(2) Yang–Mills theory containing a nonlinear spinor field, there is a mass gap; (ii) in SU(3) Proca–Higgs theory, there are flux tube solutions with a longitudinal electric field required for producing a force binding quarks; (iii) in non-Abelian Proca–Higgs theories, there exist flux tube solutions with a momentum directed along the tube axis and particlelike solutions with a nonvanishing total angular momentum created by crossed (...) color electric and magnetic fields; in QCD, such configurations may contribute to the proton spin. We discuss the conjecture that such non-QCD theories might be a consequence of approximate solution of an infinite set of Dyson–Schwinger equations describing the procedure of nonperturbative quantization. The phenomenon of dimensional transmutation for nonperturbative quantization and the analogy between nonperturbative quantization and turbulence modeling are also discussed. (shrink)

We present the theory of Dirac spinors in the formulation given by Bohm on the idea of de Broglie: the quantum relativistic matter field is equivalently re-written as a special type of classical fluid and in this formulation it is shown how a relativistic environment can host the non-local aspects of the above-mentioned hidden-variables theory. Sketches for extensions are given at last.

Professor Chen Ning Yang, an eminent contemporary physicist, was Professor at the Institute for Advanced Study, Princeton, New Jersey, from 1955 to 1966, and Albert Einstein Professor of Physics at the State University of New York at Stony Brook until his retirement in 1999. He has been Distinguished Professor-at-Large at the Chinese University of Hong Kong since 1986 and Professor at Tsinghua University, Beijing, since 1998. Since receiving his PhD from the University of Chicago in 1948, Prof Yang has made (...) great impacts in both abstract theory and phenomenological analysis in modern physics. In 1983, he published "Selected Papers (1945-1980), With Commentary". It has been considered by Freeman Dyson as one of his favorite books. The present book is a sequel to that earlier volume. It is a collection of his personally selected papers (1971-2012) supplemented by his insightful commentaries. Its contents reflect Professor Yang's changing interests after he reached age sixty. It also includes commentaries written by him in 2011 when he is 89 years old. The papers and commentaries in this unique collection comprise a remarkable personal and professional chronicle, shedding light on both the intellectual development of a great physicist and on the nature of scientific inquiry. (shrink)

Presents a history of physics from the dawn of science to the present through coverage of one hundred scientific breakthroughs in the discipline, including force and inertia, hidden heat, the Doppler effect, cloud chambers, and string theory.

The recently celebrated discovery of the Higgs boson has captivated the public's imagination with the promise that it can explain the origins of everything in the universe. It's no wonder that the media refers to it grandly as the "God particle." Yet behind closed doors, physicists are admitting that there is much more to this story, and even years of gunning the Large Hadron Collider and herculean number crunching may still not lead to a deep understanding of the laws of (...) nature. In this fascinating and eye-opening account, theoretical physicist Alexander Unzicker and science writer Sheilla Jones offer a polemic. They question whether the large-scale, multinational enterprises actually lead us to the promised land of understanding the universe. The two scientists take us on a tour of contemporary physics and show how a series of highly publicized theories met a dead end. Unzicker and Jones systematically unpack the recent hot theories such as "parallel universes," "string theory," and "inflationary cosmology," and provide an accessible explanation of each. They argue that physics has abandoned its evidence-based roots and shifted to untestable mathematical theories, and they issue a clarion call for the science to return to its experimental foundation. (shrink)