Foundations of Physics

ISSN: 0015-9018

60 found

View year:

  1. The Decoherent Arrow of Time and the Entanglement Past Hypothesis.Jim Al-Khalili & Eddy Keming Chen - 2024 - Foundations of Physics 54 (49).
    If an asymmetry in time does not arise from the fundamental dynamical laws of physics, it may be found in special boundary conditions. The argument normally goes that since thermodynamic entropy in the past is lower than in the future according to the Second Law of Thermodynamics, then tracing this back to the time around the Big Bang means the universe must have started off in a state of very low thermodynamic entropy: the Thermodynamic Past Hypothesis. In this paper, we (...)
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  2.  5
    Revisiting the Charged Harmonic Oscillator in a Uniform Electric Field.K. Bakke - 2024 - Foundations of Physics 54 (5):1-9.
    We discuss the two-dimensional harmonic oscillator in the presence of a uniform radial electric field around a cylindrical cavity. By including the Aharonov-Bohm flux and by assuming the existence and the absence of an infinity wall located at the radius of the cylindrical cavity, we show that bound states can be achieved around the cylindrical cavity in this two-dimensional charged harmonic oscillator in a uniform radial electric field.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  3.  9
    Epistemic–Pragmatist Interpretations of Quantum Mechanics: A Comparative Assessment.Ali Barzegar & Daniele Oriti - 2024 - Foundations of Physics 54 (5):1-34.
    In this paper, we investigate similarities and differences between the main neo-Copenhagen (or “epistemic–pragmatist”) interpretations of quantum mechanics, here identified as those defined by the rejection of an ontological nature of the quantum states and the simultaneous avoidance of hidden variables, while maintaining the quantum formalism unchanged. We argue that there is a single general interpretive framework in which the core claims that the various interpretations in the class are committed to, and which they emphasize to varying degrees, can be (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  4.  10
    Self-Normalizing Path Integrals.Ivan M. Burbano & Francisco Calderón - 2024 - Foundations of Physics 54 (5):1-36.
    The normalization in the path integral approach to quantum field theory, in contrast with statistical field theory, can contain physical information. The main claim of this paper is that the inner product on the space of field configurations, one of the fundamental pieces of data required to be added to quantize a classical field theory, determines the normalization of the path integral. In fact, dimensional analysis shows that the introduction of this structure necessarily introduces a scale that is left unfixed (...)
    No categories
    Direct download (4 more)  
     
    Export citation  
     
    Bookmark  
  5.  6
    Reply to Hofer-Szabó: The PBR Theorem hasn’t been Saved.Marcoen J. T. F. Cabbolet - 2024 - Foundations of Physics 54 (5):1-3.
    Recently, in Found. Phys. 53: 64 (2023), it has been argued that there is no reality to the PBR theorem. In Found. Phys. 54: 36 (2024), Hofer-Szabó has commented that the argument is flawed and that PBR theorem remains in tact. Here we reply to Hofer-Szabó by showing that his counterargument does not hold up, concluding that the PBR theorem has been disproved.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  6.  1
    Prediction and Inference: From Models and Data to Artificial Intelligence.Luca Gammaitoni & Angelo Vulpiani - 2024 - Foundations of Physics 54 (5):1-11.
    In this paper we present a discussion of the basic aspects of the well-known problem of prediction and inference in physics, with specific attention to the role of models, the use of data and the application of recent developments in artificial intelligence. By focussing in the time evolution of dynamic system, it is shown that main difficulties in predictions arise due to the presence of few factors as: the occurrence of chaotic dynamics, the existence of many variables with very different (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  7.  2
    Complementary Detector and State Preparation Error and Classicality in the Spin-j Einstein–Podolsky–Rosen–Bohm Experiment.Anupam Garg - 2024 - Foundations of Physics 54 (5):1-36.
    The spin-j Einstein–Podolsky–Rosen–Bohm experiment is examined in the context of how the quantum theoretic probability distributions for the spin measurement outcomes are to be coarse-grained in order to yield classical behavior in the $$j \rightarrow \infty $$ limit. A coarse-graining protocol is found that can be viewed as imperfection either in the detection process or in state preparation process, and is in both viewpoints minimal in the sense that it is no more than what is needed to wash out the (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  8.  6
    Arrival Times Versus Detection Times.Sheldon Goldstein, Roderich Tumulka & Nino Zanghì - 2024 - Foundations of Physics 54 (5):1-25.
    How to compute the probability distribution of a detection time, i.e., of the time which a detector registers as the arrival time of a quantum particle, is a long-debated problem. In this regard, Bohmian mechanics provides in a straightforward way the distribution of the time at which the particle actually does arrive at a given surface in 3-space in the absence of detectors. However, as we discuss here, since the presence of detectors can change the evolution of the wave function (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  9.  3
    Conservation Laws in Quantum Database Search.Li-Yi Hsu & Ching-Hsu Chen - 2024 - Foundations of Physics 54 (5):1-13.
    Recently, the correspondence between the air track scenario and quantum database search algorithm was revealed. The conservation laws of linear momentum and nonlinear kinetic energy in the former case, which involve sequential elastic collisions, have their analogs in the latter case. Obviously, probability normalization combined with the Born rule serves as an analog for kinetic energy conservation. Here we explore the linear conservation laws in a generic quantum database search. Regarding the non-uniform distribution of the marked state, the uneven state (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  10.  7
    The Evolutionary Versus the All-at-Once Picture of Spacetime.M. Ebrahim Maghsoudi & Seyed Ali Taheri Khorramabadi - 2024 - Foundations of Physics 54 (5):1-24.
    There are two metaphysical pictures of spacetime: The evolutionary picture and the all-at-once picture. According to the evolutionary picture, spacetime is nothing but the evolution of space over time. In contrast, the all-at-once picture considers spacetime as ‘a global, four-dimensional boundary value problem’ that can be solved only in an all-at-once manner, i.e. as a whole which is fundamentally four-dimensional and non-decomposable into spatial and temporal parts. The two most-known formulations of general theory of relativity, i.e. the Hamiltonian (or the (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  11.  14
    Bayes Keeps Boltzmann Brains at Bay.Don N. Page - 2024 - Foundations of Physics 54 (5):1-5.
    Sean Carroll has recently argued that theories predicting that observations are dominated by Boltzmann Brains should be rejected because they are cognitively unstable: “they cannot simultaneously be true and justifiably believed.” While such Boltzmann Brain theories are indeed cognitively unstable, one does not need to appeal to this argumentation to reject them. Instead, they may be ruled out by conventional Bayesian reasoning, which is sufficient to keep Boltzmann Brains at bay.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  12.  2
    Freedom in the Many-Worlds Interpretation.Ovidiu Cristinel Stoica - 2024 - Foundations of Physics 54 (5):1-19.
    I analyze the possibility of free-will in the many-worlds interpretation (MWI), arguing for their compatibility. I use as a starting point Nicolas Gisin’s “The Multiverse Pandemic” (preprint arXiv:2210.05377, 2022, after Gisin, N., “L’épidémie du multivers”, in “Le Plus Grand des Hasards”, Belin, Paris, 2010), in which he makes an interesting case that MWI is contradicted by our hard to deny free-will. The counts he raised are: (1) MWI is deterministic, forcing choices on us, (2) in MWI all our possible choices (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  13.  77
    A Proposal for a Metaphysics of Self-Subsisting Structures. II. Quantum Physics.Antonio Vassallo, Pedro Naranjo & Tim Koslowski - 2024 - Foundations of Physics 54 (5):1-29.
    The paper presents an extension of the metaphysics of self-subsisting structures set out in a companion paper to the realm of non-relativistic quantum physics. The discussion is centered around a Pure Shape Dynamics model representing a relational implementation of a de Broglie-Bohm N-body system. An interpretation of this model in terms of self-subsisting structures is proposed and assessed against the background of the debate on the metaphysics of quantum physics, with a particular emphasis on the nature of the wave function. (...)
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  14.  8
    Aharonov–Bohm Effect as a Diffusion Phenomenon.Charalampos Antonakos & Andreas F. Terzis - 2024 - Foundations of Physics 54 (4):1-27.
    This paper presents a hydrodynamical view of the Aharonov–Bohm effect, using Nelson’s formulation of quantum mechanics. Our aim is to gain a better understanding of the mysteries behind this effect, such as why in the prototype Aharonov–Bohm system with a cylinder the motion of a particle is affected in a region where there is no magnetic field. Our main purpose is to use Nelson’s formulation to describe the effect and demonstrate that it can be explained by the direct action of (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  15.  11
    Position as an Independent Variable and the Emergence of the 1/2-Time Fractional Derivative in Quantum Mechanics.Marcus W. Beims & Arlans J. S. de Lara - 2024 - Foundations of Physics 54 (4):1-24.
    Using the position as an independent variable, and time as the dependent variable, we derive the function $${\mathcal{P}}^{(\pm )}=\pm \sqrt{2m({\mathcal{H}}-{\mathcal{V}}(q))}$$, which generates the space evolution under the potential $${\mathcal{V}}(q)$$ and Hamiltonian $${\mathcal{H}}$$. No parametrization is used. Canonically conjugated variables are the time and minus the Hamiltonian ( $$-{\mathcal{H}}$$ ). While the classical dynamics do not change, the corresponding Quantum operator $${{{\hat{\mathcal P}}}}^{(\pm )}$$ naturally leads to a 1/2-fractional time evolution, consistent with a recent proposed space–time symmetric formalism of the Quantum (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  16.  21
    Quantum Reconstructions as Stepping Stones Toward ψ-Doxastic Interpretations?Philipp Berghofer - 2024 - Foundations of Physics 54 (4):1-24.
    In quantum foundations, there is growing interest in the program of reconstructing the quantum formalism from clear physical principles. These reconstructions are formulated in an operational framework, deriving the formalism from information-theoretic principles. It has been recognized that this project is in tension with standard _ψ-ontic_ interpretations. This paper presupposes that the quantum reconstruction program (QRP) (i) is a worthwhile project and (ii) puts pressure on _ψ-ontic_ interpretations. Where does this leave us? Prima facie, it seems that _ψ-epistemic_ interpretations perfectly (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  17.  13
    Addendum to ‘On the Nonreality of the PBR Theorem’: Disproof by Generic Counterexample.Marcoen J. T. F. Cabbolet - 2024 - Foundations of Physics 54 (4):1-9.
    The PBR theorem is widely seen as one of the most important no-go theorems in the foundations of quantum mechanics. Recently, in Cabbolet (Found Phys 53(3):64, 2023), it has been argued that there is no reality to the PBR theorem using a pair of bolts as a counterexample. In this addendum we expand on the argument: we disprove the PBR theorem by a generic counterexample, and we put the finger on the precise spot where Pusey, Barrett, and Rudolph have made (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  18.  9
    The Radiation Field, at the Origin of the Quantum Canonical Operators.A. M. Cetto & L. De la Peña - 2024 - Foundations of Physics 54 (4):1-20.
    We show that the electromagnetic radiation field, conventionally introduced as a perturbation in quantum mechanics, is actually at the basis of the operator formalism. We first analyze the linear resonant response of the (continuous) variables x(t), p(t) of a harmonic oscillator to the full radiation field, i.e. the zero-point field plus an applied field playing the role of the driving force, and then extend the analysis to the response of a charged particle bound by a non-linear force, typically an atomic (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  19.  12
    Quantum Physics, Digital Computers, and Life from a Holistic Perspective.George F. R. Ellis - 2024 - Foundations of Physics 54 (4):1-29.
    Quantum physics is a linear theory, so it is somewhat puzzling that it can underlie very complex systems such as digital computers and life. This paper investigates how this is possible. Physically, such complex systems are necessarily modular hierarchical structures, with a number of key features. Firstly, they cannot be described by a single wave function: only local wave functions can exist, rather than a single wave function for a living cell, a cat, or a brain. Secondly, the quantum to (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  20.  19
    Does Locality Imply Reality of the Wave Function? Hardy’s Theorem Revisited.Shan Gao - 2024 - Foundations of Physics 54 (4):1-12.
    Hardy’s $$\psi$$ -ontology theorem proves the reality of the wave function under the assumption of restricted ontic indifference. It has been conjectured that restricted ontic indifference, which is a very strong assumption from the $$\psi$$ -epistemic view, can be derived from two weaker sub-assumptions: an ontic state assumption and a locality assumption. However, Leifer argued that this derivation cannot go through when considering the existence of the vacuum state in the second-quantized description of quantum states. In this paper, I present (...)
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  21.  11
    On the Reality of the Quantum State Once Again: A No-Go Theorem for $$\psi$$ -Ontic Models?Shan Gao - 2024 - Foundations of Physics 54 (4):1-6.
    In a recent paper (Found Phys 54:14, 2024), Carcassi, Oldofredi and Aidala concluded that the \(\psi\) -ontic models defined by Harrigan and Spekkens cannot be consistent with quantum mechanics, since the information entropy of a mixture of non-orthogonal states are different in these two theories according to their information theoretic analysis. In this paper, I argue that this no-go theorem for \(\psi\) -ontic models is false by explaining the physical origin of the von Neumann entropy in quantum mechanics.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  22.  8
    Symplectic Quantization III: Non-relativistic Limit.Giacomo Gradenigo, Roberto Livi & Luca Salasnich - 2024 - Foundations of Physics 54 (4):1-19.
    First of all we shortly illustrate how the symplectic quantization scheme (Gradenigo and Livi, Found Phys 51(3):66, 2021) can be applied to a relativistic field theory with self-interaction. Taking inspiration from the stochastic quantization method by Parisi and Wu, this procedure is based on considering explicitly the role of an intrinsic time variable, associated with quantum fluctuations. The major part of this paper is devoted to showing how the symplectic quantization scheme can be extended to the non-relativistic limit for a (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  23.  10
    Anti-foundationalist Coherentism as an Ontology for Relational Quantum Mechanics.Emma Jaura - 2024 - Foundations of Physics 54 (4):1-21.
    There have been a number of recent attempts to identify the best metaphysical framework for capturing Rovelli’s Relational Quantum Mechanics (RQM). All such accounts commit to some form of fundamentalia, whether they be traditional objects, physical relations, events or ‘flashes’, or the cosmos as a fundamental whole. However, Rovelli’s own recommendation is that ‘a natural philosophical home for RQM is an anti-foundationalist perspective' (Rovelli in Philos Trans R Soc 376:10, 2018). This gives us some prima facie reason to explore options (...)
    No categories
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  24.  15
    Comment on Aurélien Drezet’s Defense of Relational Quantum Mechanics.Jay Lawrence, Marcin Markiewicz & Marek Żukowski - 2024 - Foundations of Physics 54 (4):1-5.
    Aurélien Drezet has attempted in Found. Phys. 54(1), 5 (2023) to defend Relational Quantum Mechanics (RQM) against our recent critique, entitled Relational Quantum Mechanics is incompatible with quantum mechanics, published in Quantum 7, 1015 (2023). Drezet not only misrepresents our work, but he also misconstructs the very theory (RQM) that he claims to defend.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  25.  5
    sQFT: An Autonomous Explanation of the Interactions of Quantum Particles.K. -H. Rehren, L. T. Cardoso, C. Gass, J. M. Gracia-Bondía, B. Schroer & J. C. Várilly - 2024 - Foundations of Physics 54 (4):1-25.
    Successful applications of a conceptually novel setup of Quantum Field Theory, that accounts for all subtheories of the Standard Model (QED, Electroweak Interaction and Higgs, Yang–Mills and QCD) and beyond (Helicity 2), call for a perspective view in a broader conceptual context. The setting is “autonomous” in the sense of being intrinsically quantum. Its principles are: Hilbert space, Poincaré symmetry and causality. Its free quantum fields are obtained from Wigner’s unitary representations of the Poincaré group, with only physical and observable (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  26.  10
    Relational Quantum Mechanics and Contextuality.Calum Robson - 2024 - Foundations of Physics 54 (4):1-22.
    This paper discusses the question of stable facts in relational quantum mechanics (RQM). I examine how the approach to quantum logic in the consistent histories formalism can be used to clarify what infomation about a system can be shared between different observers. I suggest that the mathematical framework for Consistent Histories can and should be incorporated into RQM, whilst being clear on the interpretational differences between the two approaches. Finally I briefly discuss two related issues: the similarities and differences between (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  27.  10
    Exploring the Interplay Between Wave Function Realism and Gauge Symmetry Interpretations in Quantum Mechanics.Marco Sanchioni - 2024 - Foundations of Physics 54 (4):1-18.
    This paper examines the tension between wave function realism and interpretations of gauge symmetries within quantum mechanics. We explore how traditional views of gauge symmetries as descriptive redundancies challenge the principles of wave function realism, which regards the wave function as a real entity. By noting that, through the case study of a quantum particle in an electromagnetic field, gauge transformations impact the wave function’s phase, we present a dilemma for wave function realism. We discuss potential resolutions, including redefining ontological (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  28.  8
    Correction: Quantum Mechanics Based on an Extended Least Action Principle and Information Metrics of Vacuum Fluctuations.Jianhao M. Yang - 2024 - Foundations of Physics 54 (4):1-1.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  29.  16
    On Fermi’s Resolution of the “4/3 Problem” in the Classical Theory of the Electron.Donato Bini, Andrea Geralico, Robert T. Jantzen & Remo Ruffini - 2024 - Foundations of Physics 54 (3):1-44.
    We discuss the solution proposed by Fermi to the so called “4/3 problem” in the classical theory of the electron, a problem which puzzled the physics community for many decades before and after his contribution. Unfortunately his early resolution of the problem in 1922–1923 published in three versions in Italian and German journals (after three preliminary articles on the topic) went largely unnoticed. Even more recent texts devoted to classical electron theory still do not present his argument or acknowledge the (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  30.  16
    Simulating Nelsonian Quantum Field Theory.Andrea Carosso - 2024 - Foundations of Physics 54 (3):1-31.
    We describe the picture of physical processes suggested by Edward Nelson’s stochastic mechanics when generalized to quantum field theory regularized on a lattice, after an introductory review of his theory applied to the hydrogen atom. By performing numerical simulations of the relevant stochastic processes, we observe that Nelson’s theory provides a means of generating typical field configurations for any given quantum state. In particular, an intuitive picture is given of the field “beable”—to use a phrase of John Stewart Bell—corresponding to (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  31.  29
    Univalence and Ontic Structuralism.Lu Chen - 2024 - Foundations of Physics 54 (3):1-27.
    The persistent challenge of formulating ontic structuralism in a rigorous manner, which prioritizes structures over the entities they contain, calls for a transformation of traditional logical frameworks. I argue that Univalent Foundations (UF), which feature the axiom that all isomorphic structures are identical, offer such a foundation and are more attractive than other proposed structuralist frameworks. Furthermore, I delve into the significance in the case of the hole argument and, very briefly, the nature of symmetries.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  32.  21
    Beyond the Quantum Membrane Paradigm: A Philosophical Analysis of the Structure of Black Holes in Full QG.Enrico Cinti & Marco Sanchioni - 2024 - Foundations of Physics 54 (3):1-23.
    This paper presents a philosophical analysis of the structure of black holes, focusing on the event horizon and its fundamental status. While black holes have been at the centre of countless paradoxes arising from the attempt to merge quantum mechanics and general relativity, recent experimental discoveries have emphasised their importance as objects for the development of Quantum Gravity. In particular, the statistical mechanical underpinning of black hole thermodynamics has been a central research topic. The Quantum Membrane Paradigm, proposed by Wallace (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  33.  17
    Relational Quantum Mechanics and Intuitionistic Mathematics.Charles B. Crane - 2024 - Foundations of Physics 54 (3):1-12.
    We propose a model of physics that blends Rovelli’s relational quantum mechanics (RQM) interpretation with the language of finite information quantities (FIQs), defined by Gisin and Del Santo in the spirit of intuitionistic mathematics. We discuss deficiencies of using real numbers to model physical systems in general, and particularly under the RQM interpretation. With this motivation for an alternative mathematical language, we propose the use of FIQs to model the world under the RQM interpretation, wherein we view the propensities that (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  34.  12
    Has the Problem of the Motion of a Heavy Symmetric Top been Solved in Quadratures?Alexei A. Deriglazov - 2024 - Foundations of Physics 54 (3):1-10.
    We have revised the problem of the motion of a heavy symmetric top. When formulating equations of the Lagrange top with the diagonal inertia tensor, the potential energy has more complicated form as compared with that assumed in the literature on dynamics of a rotating body. This implies the corresponding improvements in equations of motion. Using the Liouville’s theorem, we solve the improved equations in quadratures and present the explicit expressions for the resulting elliptic integrals.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  35.  15
    A Case Study for Leibnizian Ideas in Wolfram Model.Furkan Semih Dündar - 2024 - Foundations of Physics 54 (3):1-16.
    We study implications of Leibnizian ideas such as the identity of indiscernibles, and variety (due to Barbour and Smolin) in the context of Wolfram Model, which has been put forward in 2020. We have provided (at the moment) speculative interpretations for Leibnizian and non-Leibnizian hypergraphs. We introduced an action based on variety, to select paths where it is maximized. The specific universe which is of concern here is the one with name ‘wm1268’ from the Registry of Notable Universe Models, which (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  36.  10
    A de Broglie–Bohm Model of Pure Shape Dynamics: N-Body system.Pooya Farokhi, Tim Koslowski, Pedro Naranjo & Antonio Vassallo - 2024 - Foundations of Physics 54 (3):1-26.
    We provide the construction of a de Broglie–Bohm model of the N-body system within the framework of Pure Shape Dynamics. The equation of state of the curve in shape space is worked out, with the instantaneous shape being guided by a wave function. In order to get a better understanding of the dynamical system, we also give some numerical analysis of the 3-body case. Remarkably enough, our simulations typically show the attractor-driven behaviour of complexity, well known in the classical case, (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  37.  40
    Phenomenology, Perspectivalism and (Quantum) Physics.Steven French - 2024 - Foundations of Physics 54 (3):1-18.
    It has been claimed that Massimi’s recent perspectival approach to science sits in tension with a realist stance. I shall argue that this tension can be defused in the quantum context by recasting Massimi’s perspectivalism within a phenomenological framework. I shall begin by indicating how the different but complementary forms of the former are manifested in the distinction between certain so-called ‘-epistemic’ and ‘-ontic’ understandings of quantum mechanics, namely QBism and Relational Quantum Mechanics, respectively. A brief consideration of Dieks’ perspectivism (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  38. Bohr on EPR, the Quantum Postulate, Determinism, and Contextuality.Zachary Hall - 2024 - Foundations of Physics 54 (3):1-35.
    The famous EPR article of 1935 challenged the completeness of quantum mechanics and spurred decades of theoretical and experimental research into the foundations of quantum theory. A crowning achievement of this research is the demonstration that nature cannot in general consist in noncontextual pre-measurement properties that uniquely determine possible measurement outcomes, through experimental violations of Bell inequalities and Kochen-Specker theorems. In this article, I reconstruct an argument from Niels Bohr’s writings that the reality of the Einstein-Planck-de Broglie relations alone implies (...)
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  39.  19
    PBR, Nonreality and Entangled Measurement.Gábor Hofer-Szabó - 2024 - Foundations of Physics 54 (3):1-7.
    In a recent paper, Cabbolet argues that the PBR theorem is nonreal since in the ensemble interpretation of quantum mechanics the entangled measurement used in the derivation of the PBR theorem is nonexisting. However, Cabbolet (1) does not provide any argument for the nonexistence of entangled measurements beyond the incompatibility of the existence of entangled measurements and the existence of $$\psi$$ -epistemic models which we already know from the PBR theorem; and (2) he does not show why it is more (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  40.  14
    Relational Quantum Mechanics: Ozawa’s Intersubjectivity Theorem as Justification of the Postulate on Internally Consistent Descriptions.Andrei Khrennikov - 2024 - Foundations of Physics 54 (3):1-12.
    The Ozawa’s intersubjectivity theorem (OIT) proved within quantum measurement theory supports the new postulate of relational quantum mechanics (RQM), the postulate on internally consistent descriptions. But from OIT viewpoint postulate’s formulation should be completed by the assumption of probability reproducibility. We remark that this postulate was proposed only recently to resolve the problem of intersubjectivity of information in RQM. In contrast to RQM for which OIT is a supporting theoretical statement, QBism is challenged by OIT.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  41.  16
    Foundational Issues in Group Field Theory.Álvaro Mozota Frauca - 2024 - Foundations of Physics 54 (3):1-24.
    In this paper I offer an introduction to group field theory (GFT) and to some of the issues affecting the foundations of this approach to quantum gravity. I first introduce covariant GFT as the theory that one obtains by interpreting the amplitudes of certain spin foam models as Feynman amplitudes in a perturbative expansion. However, I argue that it is unclear that this definition of GFTs amounts to something beyond a computational rule for finding these transition amplitudes and that GFT (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  42.  33
    Eliminating the ‘Impossible’: Recent Progress on Local Measurement Theory for Quantum Field Theory.Maria Papageorgiou & Doreen Fraser - 2024 - Foundations of Physics 54 (3):1-75.
    Arguments by Sorkin (Impossible measurements on quantum fields. In: Directions in general relativity: proceedings of the 1993 International Symposium, Maryland, vol 2, pp 293–305, 1993) and Borsten et al. (Phys Rev D 104(2), 2021. https://doi.org/10.1103/PhysRevD.104.025012 ) establish that a natural extension of quantum measurement theory from non-relativistic quantum mechanics to relativistic quantum theory leads to the unacceptable consequence that expectation values in one region depend on which unitary operation is performed in a spacelike separated region. Sorkin [ 1 ] labels (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  43.  15
    On the Growing Universe of Causal Set Theory—An Order-Type Approach.Tomasz Placek & Leszek Wroński - 2024 - Foundations of Physics 54 (3):1-30.
    We investigate a model of becoming—classical sequential growth (CSG)—that has been proposed within the framework of causal sets (causets), with the latter defined as order types of certain partial orderings. To investigate how causets grow, we introduce special sequences of causets, which we call “csg-paths”. We prove a number of results concerning relations between csg-paths and causets. These results paint a highly non-trivial picture of csg-paths. There are uncountably many csg-paths, all of them sharing the same beginning, after which they (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  44.  20
    The Thermodynamic Cost of Choosing.Carlo Rovelli - 2024 - Foundations of Physics 54 (3):1-9.
    Choice can be defined in thermodynamical terms, and shown to have a thermodynamic cost: choosing between a binary alternative at temperature T dissipates an energy $$E\ge kT\ln 2$$.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  45.  13
    Minkowski Space from Quantum Mechanics.László B. Szabados - 2024 - Foundations of Physics 54 (3):1-48.
    Penrose’s Spin Geometry Theorem is extended further, from SU(2) and E(3) (Euclidean) to E(1, 3) (Poincaré) invariant elementary quantum mechanical systems. The Lorentzian spatial distance between any two non-parallel timelike straight lines of Minkowski space, considered to be the centre-of-mass world lines of E(1, 3)-invariant elementary classical mechanical systems with positive rest mass, is expressed in terms of E(1, 3)-invariant basic observables, viz. the 4-momentum and the angular momentum of the systems. An analogous expression for E(1, 3)-invariant elementary quantum mechanical (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  46.  21
    Quantum Mechanics Based on an Extended Least Action Principle and Information Metrics of Vacuum Fluctuations.Jianhao M. Yang - 2024 - Foundations of Physics 54 (3):1-31.
    We show that the formulations of non-relativistic quantum mechanics can be derived from an extended least action principle. The principle can be considered as an extension of the least action principle from classical mechanics by factoring in two assumptions. First, the Planck constant defines the minimal amount of action a physical system needs to exhibit during its dynamics in order to be observable. Second, there is constant vacuum fluctuation along a classical trajectory. A novel method is introduced to define the (...)
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  47.  15
    Convivial Solipsism as a Maximally Perspectival Interpretation.Hervé Zwirn - 2024 - Foundations of Physics 54 (3):1-16.
    A classification of different interpretations of the quantum formalism is examined and the concept of perspectival interpretation is presented. A perspectival interpretation implies that the truth is relative to the observer. The degree to which Convivial Solipsism and QBism in its different versions are perspectival is examined.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  48.  29
    Why the Global Phase is Not Real.Shan Gao - 2024 - Foundations of Physics 54 (2):1-6.
    In this paper, I present a new analysis of the meaning of the phase in quantum mechanics. First, I give a simple but rigorous proof that the global phase is not real in $$\psi$$ -ontic quantum theories. Next, I argue that a similar strategy cannot be used to prove the reality of the global phase due to the existence of the tails of the wave function. Finally, I argue that the relative phase is not a nonlocal property of two regions (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  49.  19
    Eliminativism and the QCD $$\theta _{\text {YM}}$$-Term: What Gauge Transformations Cannot Do.Henrique Gomes & Aldo Riello - 2024 - Foundations of Physics 54 (2):1-30.
    The eliminative view of gauge degrees of freedom—the view that they arise solely from descriptive redundancy and are therefore eliminable from the theory—is a lively topic of debate in the philosophy of physics. Recent work attempts to leverage properties of the QCD $$\theta _{\text {YM}}$$ θ YM -term to provide a novel argument against the eliminative view. The argument is based on the claim that the QCD $$\theta _{\text {YM}}$$ θ YM -term changes under “large” gauge transformations. Here we review (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  50.  24
    A No-Go Result on Observing Quantum Superpositions.Guang Ping He - 2024 - Foundations of Physics 54 (2):1-11.
    We give a general proof showing that if the evolution from one state to another is not reversible, then the projective measurements on the superposition of these two states are impossible. Applying this no-go result to the Schrödinger’s cat paradox implies that if something is claimed to be a real Schrödinger’s cat, there will be no measurable difference between it and a trivial classical mixture of ordinary cats in any physically implementable process, unless raising the dead becomes reality. Other similar (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  51.  19
    Spatio-temporally Graded Causality: A Model.Bartosz Jura - 2024 - Foundations of Physics 54 (2):1-12.
    In this paper we consider a claim that in the natural world there is no fact of the matter about the spatio-temporal separation of events. In order to make sense of such a notion and construct useful models of the world, it is proposed to use elements of a non-classical logic. Specifically, we focus here on causality, as a concept tightly related with the assumption of there being distinct, separate events, proposing a model according to which it can be considered (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  52.  41
    Stern–Gerlach, EPRB and Bell Inequalities: An Analysis Using the Quantum Hamilton Equations of Stochastic Mechanics.Wolfgang Paul & Michael Beyer - 2024 - Foundations of Physics 54 (2):1-25.
    The discussion of the recently derived quantum Hamilton equations for a spinning particle is extended to spin measurement in a Stern–Gerlach experiment. We show that this theory predicts a continuously changing orientation of the particles magnetic moment over the course of its motion across the Stern–Gerlach apparatus. The final measurement results agree with experiment and with predictions of the Pauli equation. Furthermore, the Einstein–Podolsky–Rosen–Bohm thought experiment is investigated, and the violation of Bells’s inequalities is reproduced within this stochastic mechanics approach. (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  53.  63
    A Stochastic Model of Mathematics and Science.David H. Wolpert & David B. Kinney - 2024 - Foundations of Physics 54 (2):1-67.
    We introduce a framework that can be used to model both mathematics and human reasoning about mathematics. This framework involves stochastic mathematical systems (SMSs), which are stochastic processes that generate pairs of questions and associated answers (with no explicit referents). We use the SMS framework to define normative conditions for mathematical reasoning, by defining a “calibration” relation between a pair of SMSs. The first SMS is the human reasoner, and the second is an “oracle” SMS that can be interpreted as (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  54.  57
    What Does ‘(Non)-absoluteness of Observed Events’ Mean?Emily Adlam - 2024 - Foundations of Physics 54 (1):1-43.
    Recently there have emerged an assortment of theorems relating to the ‘absoluteness of emerged events,’ and these results have sometimes been used to argue that quantum mechanics may involve some kind of metaphysically radical non-absoluteness, such as relationalism or perspectivalism. However, in our view a close examination of these theorems fails to convincingly support such possibilities. In this paper we argue that the Wigner’s friend paradox, the theorem of Bong et al and the theorem of Lawrence et al are all (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   3 citations  
  55.  36
    On the Reality of the Quantum State Once Again: A No-Go Theorem for ψ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\psi$$\end{document}-Ontic Models. [REVIEW]Christine A. Aidala, Andrea Oldofredi & Gabriele Carcassi - 2024 - Foundations of Physics 54 (1):1-15.
    In this paper we show that ψ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\psi$$\end{document}-ontic models, as defined by Harrigan and Spekkens (HS), cannot reproduce quantum theory. Instead of focusing on probability, we use information theoretic considerations to show that all pure states of ψ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\psi$$\end{document}-ontic models must be orthogonal to each other, in clear violation of quantum mechanics. Given that (i) Pusey, Barrett and Rudolph (PBR) previously showed that ψ\documentclass[12pt]{minimal} \usepackage{amsmath} (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   2 citations  
  56.  21
    Learning from Paradoxes.Alessandro Bettini - 2024 - Foundations of Physics 54 (1):1-26.
    George Francis FitzGerald is well known to have proposed in 1889, three years before Lorentz, the (physical) contraction of bodies moving in the hypothetical ether, as an “explanation” the null result of the Michelson and Morley experiment. Less known is his proposal of an ether-drift experiment based on an electrostatic system. A simple charged condenser suspended by a wire would be subject to a torque due to the earth’s motion. The experiment was done by his pupil Trouton, with Noble, with (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  57.  17
    Reconstruction of f(R) Gravity from Cosmological Unified Dark Fluid Model.Esraa Ali Elkhateeb - 2024 - Foundations of Physics 54 (1):1-19.
    In this work, we reconstruct the cosmological unified dark fluid model proposed previously by Elkhateeb (Astrophys Space Sci 363(1):7, 2018) in the framework of _f_(_R_) gravity. Utilizing the equivalence between the scalar-tensor theory and the _f_(_R_) gravity theory, the scalar field for the dark fluid is obtained, whence the _f_(_R_) function is extracted and its viability is discussed. The _f_(_R_) functions and the scalar field potentials have then been extracted in the early and late times of asymptotically de Sitter spacetime. (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  58.  31
    Schrödinger Cats and Quantum Complementarity.Lorenzo Maccone - 2024 - Foundations of Physics 54 (1):1-10.
    Complementarity tells us we cannot know precisely the values of all the properties of a quantum object at the same time: the precise determination of one property implies that the value of some other (complementary) property is undefined. E.g. the precise knowledge of the position of a particle implies that its momentum is undefined. Here we show that a Schrödinger cat has a well defined value of a property that is complementary to its “being dead or alive” property. Then, thanks (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  59.  26
    Fundamental Units in Gravitational, Electromagnetic and Weak (Fermi) Interactions.M. Novello & V. Antunes - 2024 - Foundations of Physics 54 (1):1-5.
    In analogy with Planck’s construction of fundamental quantities in gravitation, we construct fundamental quantities associated with (1) theories of electrodynamics in which the electromagnetic field has a maximum value (e.g. Born-Infeld theory), and (2) the Fermi interaction. This gives us a maximum intensity of the electromagnetic field, and also reveals a close relationship between the fundamental lengths associated with the gravitational and weak interactions, supporting the connection between these two interactions.
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
  60.  27
    Non-Relativistic Regime and Topology: Topological Term in the Einstein Equation.Quentin Vigneron - 2024 - Foundations of Physics 54 (1):1-47.
    We study the non-relativistic (NR) limit of relativistic spacetimes in relation with the topology of the Universe. We first show that the NR limit of the Einstein equation is only possible in Euclidean topologies, i.e., for which the covering space is \(\mathbb {E}^3\). We interpret this result as an inconsistency of general relativity in non-Euclidean topologies and propose a modification of that theory which allows for the limit to be performed in any topology. For this, a second reference non-dynamical connection (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark  
 Previous issues
  
Next issues