Matrix Mechanics Mis-Prized: Max Born’s Belated Nobelization. (arXiv:2306.00842v1 [physics.hist-ph]) |

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physics.hist-ph updates on arXiv.org

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John L. Heilbron, Carlo Rovelli

Sat Jun 03 2023 09:28:42 (5 minutes)

# 1.

We examine evaluations of the contributions of Matrix Mechanics and Max Born to the formulation of quantum mechanics from Heisenberg’s Helgoland paper of 1925 to Born’s Nobel Prize of 1954. We point out that the process of evaluation is continuing in the light of recent interpretations of the theory that deemphasize the importance of the wave function.

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Aurélien Drezet

Sat Jun 03 2023 09:28:41 (5 minutes)

# 2.

The Relational Quantum Mechanics (RQM) is an alternative interpretation of quantum mechanics that was proposed originally by C.~Rovelli. RQM can be seen as a logical completion and generalization of the Copenhagen (orthodox) interpretation but where the arbitrariness of Heisenberg’s quantum `shifty-split’ or `cut’, which is separating observed and observing subsystems, is taken more seriously. Unlike, the Copenhagen interpretation the cut is not confined to the macroscopic domain and the roles of observed and observing systems are relative and can be inverted. RQM is therefore a more symmetric and general approach.\\ Moreover, recently RQM has been criticized and assessed by various authors. The aim of the present comment is to give a short reply to the recent J.~Lawrence et al. article [arxiv: 2210.09025] that concerns RQM and the role of quantum contextuality.

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Thu Jun 01 2023 23:58:20 (1 day)

# 3.

Dürr, Patrick and Read, James (2023) Reconsidering Conventionalism: An Invitation to a Sophisticated Philosophy for Modern (Space-)Times. [Preprint]

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Thu Jun 01 2023 23:57:23 (1 day)

# 4.

Farr, Matt (2023) The Three-Times Problem. [Preprint]

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Thu Jun 01 2023 00:29:21 (2 days)

# 5.

Stuart, Michael T. and Fehige, Yiftach (2021) Motivating the History of the Philosophy of Thought Experiments. HOPOS: The Journal of the International Society for the History of Philosophy of Science, 11. pp. 212-221.

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Thu Jun 01 2023 00:28:28 (2 days)

# 6.

Gao, Shan (2023) Can the ontology of Bohmian mechanics include only particles? [Preprint]

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Thu Jun 01 2023 00:28:00 (2 days)

# 7.

Erfanifar, T (2023) A new perspective on No Miracle Argument. [Preprint]

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Tue May 30 2023 05:18:56 (4 days)

# 8.

Earman, John (2023) Evaluating the Symmetry to Reality Inference: Not All Symmetry Signals Redundancy. [Preprint]

]]>Sequential measurements and the Kochen-Specker arguments |

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Sat May 27 2023 07:52:15 (1 hour)

# 1.

Gábor, Hofer-Szabó (2023) Sequential measurements and the Kochen-Specker arguments. [Preprint]

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Sat May 27 2023 07:49:13 (1 hour)

# 2.

Gomori, Marton and Hoefer, Carl (2023) Classicality and Bell’s Theorem. [Preprint]

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by

Inge S. Helland

Fri May 26 2023 09:19:34 (1 day)

# 3.

An alternative approach towards quantum theory is described, and tentative attempts to connect his approach to special and general relativity are discussed. Important concepts ar gauge groups and information/entropy connected to some physical systems. Some recent results on information in connection to black holes are touched upon. The discussions here must be considered to be preliminary.

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Nemanja Kaloper

Fri May 26 2023 09:19:32 (1 day)

# 4.

We point out that time’s arrow is generated by quantum mechanical evolution, whenever the systems have a very large number ${\cal N}$ of non-degenerate states and a Hamiltonian bounded from below. When ${\cal N}$ is finite, the arrow can be imperfect, since evolution can resurrect past states. In the limit ${\cal N} \rightarrow \infty$ the arrow is fixed by the “tooth of time”: the decay of excited states induced by {\it spontaneous emission} to the ground state, mediated by interactions and a large number of decay products which carry energy and information to infinity.

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Federico Laudisa

Fri May 26 2023 09:19:31 (1 day)

# 5.

John S. Bell introduced the notion of beable, as opposed to the standard notion of observable, in order to emphasize the need for an unambiguous formulation of quantum mechanics. In the paper I show that Bell formulated in fact two different theories of beables. The first is somehow reminiscent of the Bohr views on quantum mechanics but, at the same time, is curiously adopted by Bell as a critical tool against the Copenhagen interpretation, whereas the second, more mature formulation was among the sources of inspiration of the so-called Primitive Ontology (PO) approach to quantum mechanics, an approach inspired to scientific realism. In the first part of the paper it is argued that, contrary to the Bell wishes, the first formulation of the theory fails to be an effective recipe for addressing the ambiguity underlying the standard formulation of quantum mechanics, whereas it is only the second formulation that successfully paves the way to the PO approach. In the second part, I consider how the distinction between the two formulations of the Bell theory of beables fares vis-a-vis the complex relationship between the theory of beables and the details of the PO approach.

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Twesh Upadhyaya, William F. Braasch, Jr., Gabriel T. Landi, Nicole Yunger Halpern

Fri May 26 2023 09:19:29 (1 day)

# 6.

We extend entropy production to a deeply quantum regime involving noncommuting conserved quantities. Consider a unitary transporting conserved quantities (“charges”) between two systems initialized in thermal states. Three common formulae model the entropy produced. They respectively cast entropy as an extensive thermodynamic variable, as an information-theoretic uncertainty measure, and as a quantifier of irreversibility. Often, the charges are assumed to commute with each other (e.g., energy and particle number). Yet quantum charges can fail to commute. Noncommutation invites generalizations, which we posit and justify, of the three formulae. Charges’ noncommutation, we find, breaks the formulae’s equivalence. Furthermore, different formulae quantify different physical effects of charges’ noncommutation on entropy production. For instance, entropy production can signal contextuality – true nonclassicality – by becoming nonreal. This work opens up stochastic thermodynamics to noncommuting – and so particularly quantum – charges.

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Veronika Baumann, Caslav Brukner

Fri May 26 2023 09:19:27 (1 day)

# 7.

The Wigner’s friend experiment is a thought experiment in which a so-called superobserver (Wigner) observes another observer (the friend) who has performed a quantum measurement on a physical system. In this setup Wigner treats the friend the system and potentially other degrees of freedom involved in the friend’s measurement as one joint quantum system. In general, Wigner’s measurement changes the internal record of the friend’s measurement result such that after the measurement by the superobserver the result stored in the observer’s memory register is no longer the same as the result the friend obtained at her measurement, i.e. before she was measured by Wigner. Here, we show that any awareness by the friend of such a change, which can be modeled by an additional memory register storing the information about the change, conflicts with the no-signaling condition in extended Wigner-friend scenarios.

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Masashi Wakamatsu

Fri May 26 2023 09:19:20 (1 day)

# 8.

It is widely accepted that the Aharonov-Bohm (AB) effect is understood as local action of the vector potential generated by the solenoid on the complex phase of a charged particle’s wave functions. Nevertheless, because the vector potential is a gauge-dependent quantity, there still exist not a few researchers who claim that the AB-effect is caused by nonlocal action of the magnetic field confined inside the solenoid. A serious drawback of such non-locality explanation is that it is hard to offer definite mechanism of such nonlocal interaction between separated charge and magnetic field. This is not surprising, since the locality is the foundation of modern physics including electromagnetism and quantum mechanics. On the other hand, there recently appear some interesting attempts to explain the AB-effect through the interaction between the charged particle and the solenoid current mediated by the exchange of a virtual photon. A vital assumption of this approach is that AB-phase shift is proportional to the change of the interaction energy between the charged particle and solenoid along the path of the moving charge. Accordingly, they insist that the AB-phase change along a path does not depend on the gauge choice so that the AB-phase shift for a non-closed path is in principle measurable. In the present paper, we critically examine this astonishing conclusion with the utmost care and attention. At the same time, we try to give refreshed insight into the role of the vector potential in the interpretation of the AB-effect.

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Thu May 25 2023 07:41:48 (2 days)

# 9.

Emily, Adlam (2022) The Temporal Asymmetry of Influence is not Statistical. [Preprint]

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Thu May 25 2023 00:23:09 (2 days)

# 10.

Bennett, Marissa and Miller, Michael (2023) The conventionality of real valued quantities. In: UNSPECIFIED.

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Wed May 24 2023 00:28:45 (3 days)

# 11.

Adlam, Emily (2023) Disappearing Without a Trace: The Arrows of Time in Kent’s Solution to the Lorentzian Quantum Reality Problem. [Preprint]

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Tue May 23 2023 03:44:13 (4 days)

# 12.

Ruyant, Quentin (2021) Symmetries, Indexicality and the Perspectivist Stance. International Studies in the Philosophy of Science, 34 (1). pp. 21-39. ISSN 0269-8595

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Tue May 23 2023 03:43:31 (4 days)

# 13.

Weinberger, Naftali and Williams, Porter and Woodward, James (2023) The Worldly Infrastructure of Causation. [Preprint]

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PRL: General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

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Dominik Šafránek, Dario Rosa, and Felix C. Binder

Mon May 22 2023 18:00:00 (4 days)

# 14.

Author(s): Dominik Šafránek, Dario Rosa, and Felix C. Binder

Energy extraction is a central task in thermodynamics. In quantum physics, ergotropy measures the amount of work extractable under cyclic Hamiltonian control. As its full extraction requires perfect knowledge of the initial state, however, it does not characterize the work value of unknown or untrus…

[Phys. Rev. Lett. 130, 210401] Published Mon May 22, 2023

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Patrick Moylan

Mon May 22 2023 08:46:23 (5 days)

# 15.

Both Poincar\’e in his 1900 Festschrift paper \cite{Poincare} and Einstein in his 1905 \textsl{Annalen der Physik} article \cite{Einstein} were led to $E=mc^2$ by considering electromagnetic processes taking place in vacuo. Poincar\’e’s treatment is based on a generalization of the law of conservation of momentum to include radiation. Einstein’s analysis relies solely on energy conservation and the relativity principle together with certain assumptions, which have served as the source of criticism of the paper beginning with Max Planck in 1907. We show that these objections raised by Planck and others can be traced back to Einstein’s failure to make use of momentum considerations. Relevance of our findings to a proper understanding of Ives’ criticism of Einstein’s paper is pointed out.

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Mon May 22 2023 06:17:30 (5 days)

# 16.

Rovelli, Carlo and Heilbron, John (2023) Matrix Mechanics Mis-Prized: Max Born’s Belated Nobelization. [Preprint]

The Lorentz Transformation in a Fishbowl: A Comment on Cheng and Read’s “Why Not a Sound Postulate?”

*Foundations of Physics* volume 53, Article number: 55 (2023)

Gravitational Machines. (arXiv:2305.10470v1 [gr-qc]) |

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physics.hist-ph updates on arXiv.org

by

Freeman J. Dyson

Fri May 19 2023 09:37:27 (1 day)

# 1.

A gravitational machine is defined as an arrangement of gravitating masses from which useful energy can be extracted. It is shown that such machines may exist if the masses are of normal astronomical size. A simple example of a gravitational machine, consisting of a double star with smaller masses orbiting around it, is described. It is shown that an efficient gravitational machine will also be an emitter of gravitational radiation. The emitted radiation sets a limit on the possible performance of gravitational machines, and also provides us with a possible means for detecting such machines if they exist.

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Galina Weinstein

Fri May 19 2023 09:37:26 (1 day)

# 2.

There has been a great buzz surrounding Daniel Jafferis et al.’s latest Nature paper, “Traversable wormhole dynamics on a quantum processor”. The Nature paper discusses an experiment in which Google’s Sycamore quantum processor is used to simulate a sparse N = 7 SYK model with 5 terms (a learned Hamiltonian). The Nature paper shows that the learned Hamiltonian preserves the key gravitational characteristics of an N = 10 SYK model with 210 terms and is sufficient to produce a traversable wormhole behavior. I will examine the experiment and discuss some philosophical challenges concerning the experiment in memory of Ian Hacking. Recently, Norman Yao and two graduate students discovered multiple flaws in Jafferis et al.’s learned Hamiltonian and uploaded a comment on the Nature paper. As expected, Jafferis and his team found a simple way to clarify the misunderstanding. They found a physical justification that allowed them to avoid the problem. In this paper, I elucidate the main arguments Yao and his students raised and the way Jafferis et al. found to save their learned Hamiltonian. I will end this paper with a philosophical comment on this recent development in the context of the learned Hamiltonian.

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Miguel Murça, Duarte Magano, Yasser Omar

Fri May 19 2023 09:37:23 (1 day)

# 3.

Despite the promise that fault-tolerant quantum computers can efficiently solve classically intractable problems, it remains a major challenge to find quantum algorithms that may reach computational advantage in the present era of noisy, small-scale quantum hardware. Thus, there is substantial ongoing effort to create new quantum algorithms (or adapt existing ones) to accommodate depth and space restrictions. By adopting a hybrid query perspective, we identify and characterize two methods of “breaking down” quantum algorithms into rounds of lower (query) depth, designating these approaches as “parallelization” and “interpolation”. To the best of our knowledge, these had not been explicitly identified and compared side-by-side, although one can find instances of them in the literature. We apply them to two problems with known quantum speedup: calculating the $k$-threshold function and computing a NAND tree. We show that for the first problem parallelization offers the best performance, while for the second interpolation is the better choice. This illustrates that no approach is strictly better than the other, and so that there is more than one good way to break down a quantum algorithm into a hybrid quantum-classical algorithm.

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Edgar Shaghoulian

Fri May 19 2023 09:37:15 (1 day)

# 4.

The measurement problem in quantum mechanics is almost exclusively discussed in situations where gravity is ignored. We discuss some recent developments in our understanding of quantum gravity and argue that they significantly alter the problem. Quantum gravity may even resolve one of the thorniest questions in discussions of the measurement problem: who collapses the wavefunction of the entire universe?

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Fri May 19 2023 03:10:14 (1 day)

# 5.

Iranzo-Ribera, Noelia (2017) The Status of Bohr’s Complementarity Today: A study of the nature of knowing and being. UNSPECIFIED.

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Thu May 18 2023 01:51:22 (2 days)

# 6.

Earman, John S (2023) As Revealing in the Breach as in the Observance: von Neumann’s Uniqueness Theorem. [Preprint]

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Enrique M. Padilla, Birgit L. Emberger, Manuel Diez-Minguito

Wed May 17 2023 09:19:00 (3 days)

# 7.

In 1926 Albert Einstein gave a clear explanation of the physical processes involved in the meander formation and evolution in open channels (Einstein, 1926). Although this work is far from being recognized as one of his greatest achievements, such as his annus mirabilis papers in 1905, he shows a truly remarkable didactic skills that make it easy to understand even to the non-specialist. In particular, a brilliant explanation of the tea leaf paradox can be found in this paper of 1926, presented as a simple experiment for clarifying the role of Earth rotation and flow curvature in the differential river banks erosion. This work deserves to be considered as a pioneering work that has laid a basic knowledge in currently very active research fields in fluvial geomorphology, estuarine physics, and hydraulic engineering. In response to the curiosity aroused and transmitted to the authors over the years by undergraduates and MSc. students, and also due to its historical and scientific significance, we present here the Spanish translation of Einstein’s original work published in German in 1926 in Die Naturwissenschaften (Einstein, 1926). Einstein’s drawings have not been interpreted, but just updated preserving their original spirit.

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Wed May 17 2023 00:57:27 (3 days)

# 8.

Fletcher, Samuel C. and Weatherall, James Owen (2022) The Local Validity of Special Relativity, Part 2: Matter Dynamics. [Preprint]

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Wed May 17 2023 00:56:44 (3 days)

# 9.

Fletcher, Samuel C. and Weatherall, James Owen (2022) The Local Validity of Special Relativity, Part 1: Geometry. [Preprint]

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Wed May 17 2023 00:55:09 (3 days)

# 10.

Jaksland, Rasmus (2023) Decoherence, appearance, and reality in agential realism. European Journal for Philosophy of Science. ISSN 1879-4912

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Wed May 17 2023 00:54:10 (3 days)

# 11.

Asenjo, Felipe and Hojman, Sergio and Linnemann, Niels and Read, James (2023) Abnormal light signals and the underdetermination of theory by evidence in astrophysics. [Preprint]

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Wed May 17 2023 00:53:04 (3 days)

# 12.

Tasdan, Ufuk I and Thebault, Karim P Y (2023) Spacetime Conventionalism Revisited. [Preprint]

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Tue May 16 2023 01:00:40 (4 days)

# 13.

Linnemann, Niels and Read, James and Teh, Nicholas (2023) The local validity of special relativity from an EFT-inspired perspective. [Preprint]

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Tue May 16 2023 00:58:10 (4 days)

# 14.

Bacciagaluppi, Guido (2023) A Proof of Specker’s Principle. [Preprint]

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PRL: General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

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Thorsten Emig and Giuseppe Bimonte

Mon May 15 2023 18:00:00 (4 days)

# 15.

Author(s): Thorsten Emig and Giuseppe Bimonte

Recent measurements of Casimir forces have provided evidence of an intricate modification of quantum fluctuations of the electromagnetic field in complex geometries. Here we introduce a multiple scattering description for Casimir interactions between bodies of arbitrary shape and material compositio…

[Phys. Rev. Lett. 130, 200401] Published Mon May 15, 2023

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Joseph Broz, Bingran You, Sumanta Khan, Hartmut Häffner, David E. Kaplan, and Surjeet Rajendran

Mon May 15 2023 18:00:00 (4 days)

# 16.

Author(s): Joseph Broz, Bingran You, Sumanta Khan, Hartmut Häffner, David E. Kaplan, and Surjeet Rajendran

Quantum mechanics requires the time evolution of the wave function to be linear. While this feature has been associated with the preservation of causality, a consistent causal nonlinear theory was recently developed. Interestingly, this theory is unavoidably sensitive to the full physical spread of …

[Phys. Rev. Lett. 130, 200201] Published Mon May 15, 2023

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Erik Aurell, Ryoichi Kawai

Mon May 15 2023 13:35:41 (4 days)

# 17.

G\”oran Lindblad in 1983 published a monograph on non-equilibrium thermodynamics. We here summarize the contents of this book, and provide a perspective on its relation to later developments in statistical physics and quantum physics. We high-light two aspects. The first is the idea that while all unitaries can be allowed in principle, different theories result from limiting which unitary evolutions are realized in the real world. The second is that Lindblad’s proposal for thermodynamic entropy (as opposed to information-theoretic entropy) foreshadows much more recent investigations into optimal quantum transport which is a current research focus in several fields.

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Claus Kiefer

Mon May 15 2023 13:35:40 (4 days)

# 18.

I investigate the question whether G\”odel’s undecidability theorems play a crucial role in the search for a unified theory of physics. I conclude that unless the structure of space-time is fundamentally discrete we can never decide whether a given theory is the final one or not. This is relevant for both canonical quantum gravity and string theory.

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Stefanie Reichert

Mon May 15 2023 08:00:00 (5 days)

# 19.

Nature Physics, Published online: 15 May 2023; doi:10.1038/s41567-023-02047-x

Measured expectations

]]>Why Bohr was wrong in his response to EPR. (arXiv:2305.06859v1 [quant-ph]) |

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physics.hist-ph updates on arXiv.org

by

Aurélien Drezet

Fri May 12 2023 08:56:19 (4 days)

# 1.

We assess the analysis made by Bohr in 1935 of the Einstein Podolsky Rosen paradox/theorem. We explicitly describe Bohr’s gedanken experiment involving a double-slit moving diaphragm interacting with two independent particles and show that the analysis provided by Bohr was flawed. We propose a different protocol correcting Bohr’s version that confirms EPR dilemma: Quantum mechanics is either incomplete or non-local.

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Pranay Patil, Ayushi Singhania, Jad C. Halimeh

Fri May 12 2023 08:56:18 (4 days)

# 2.

Hilbert space fragmentation is an intriguing paradigm of ergodicity breaking in interacting quantum many-body systems with applications to quantum information technology, but it is usually adversely compromised in the presence of perturbations. In this work, we demonstrate the protection of constrained dynamics arising due to a combination of mirror symmetry and Hilbert space fragmentation by employing the concept of quantum Zeno dynamics. We focus on an Ising spin ladder with carefully chosen quantum fluctuations, which in the ideal case guarantee a perfect disentanglement under Hamiltonian dynamics for a large class of initial conditions. This is known to be a consequence of the interplay of Hilbert space fragmentation with a mirror symmetry, and we show numerically the effect of breaking the latter. To evince the power of this perfect disentanglement, we study the effect of generic perturbations around the fine-tuned model, and show that we can protect against the undesirable growth of entanglement entropy by using a local Ising interaction on the rungs of the ladder. This allows us to suppress the entanglement entropy to an \textit{arbitrarily} small value for an \textit{arbitrarily} long time by controlling the strength of the rung interaction. Our work demonstrates the experimentally feasible viability of quantum Zeno dynamics in the protection of quantum information against thermalization.

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Neil Lu, Susan M. Scott, Karl Wette

Fri May 12 2023 08:56:15 (4 days)

# 3.

Neutron stars are one of the most mysterious wonders in the Universe. Their extreme densities hint at new and exotic physics at work within. Gravitational waves could be the key to unlocking their secrets. In particular, a first detection of gravitational waves from rapidly-spinning, deformed neutron stars could yield new insights into the physics of matter at extreme densities and under strong gravity. Once a first detection is made, a critical challenge will be to robustly extract physically interesting information from the detected signals. In this essay, we describe initial research towards answering this challenge, and thereby unleashing the full power of gravitational waves as an engine for the discovery of new physics.

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Savannah Garmon

Fri May 12 2023 08:00:00 (4 days)

# 4.

Nature Physics, Published online: 12 May 2023; doi:10.1038/s41567-023-02055-x

Imposing PT-symmetry and pseudo-Hermitian symmetry on an electric circuit with non-reciprocal couplings results in a complex morphology of degenerate eigenvalues that might yield new possibilities in sensing and dynamical engineering.

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Fri May 12 2023 01:04:07 (4 days)

# 5.

Weinstein, Galina (2021) Do gravitational waves confirm Hawking’s area law? [Preprint]

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Fri May 12 2023 01:03:26 (4 days)

# 6.

Lewis, Peter J. and Fallis, Don and Fitelson, Branden (2022) Accuracy-first epistemology and scientific progress. In: UNSPECIFIED.

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Fri May 12 2023 01:02:26 (4 days)

# 7.

Weinstein, Galina (2022) Maxwell’s demon and impossibility statements: Einstein on perpetuum mobile of the second kind. [Preprint]

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Fri May 12 2023 01:01:30 (4 days)

# 8.

Weinstein, Galina (2021) Demons in Black Hole Thermodynamics: Bekenstein and Hawking. [Preprint]

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Thu May 11 2023 00:36:46 (5 days)

# 9.

Freeborn, David Peter Wallis and Gilton, Marian and Mitsch, Chris (2023) Haag as a How-To Theorem. [Preprint]

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Wed May 10 2023 00:47:26 (6 days)

# 10.

Christian, Joy (2023) Bell’s Theorem Begs the Question. [Preprint]

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Wed May 10 2023 00:46:53 (6 days)

# 11.

Gao, Shan (2023) Does Bohmian mechanics solve the measurement problem? Maybe not yet. [Preprint]

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Tue May 09 2023 00:53:56 (1 week)

# 12.

Yasmineh, Salim (2022) Foundations of Quantum Mechanics. Foundations of Quantum Mechanics.

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Tue May 09 2023 00:53:12 (1 week)

# 13.

Babic, Joshua and Cocco, Lorenzo (2023) Mandersian Relationism: Space, Modality and Equivalence. Philosophy of Science. ISSN 1539-767X

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Aurélien Drezet

Mon May 08 2023 17:25:43 (1 week)

# 14.

In this chapter we discuss the Einstein Podolsky Rosen theorem and its strong relation with Bell’s theorem. We clarify some ambiguities concerning `local-realism’ and emphasize that neither realism nor determinism nor counterfactual definiteness are prerequisite of these theorems.

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Charles T. Sebens

Mon May 08 2023 17:25:42 (1 week)

# 15.

Problems of self-interaction arise in both classical and quantum field theories. To understand how such problems are to be addressed in a quantum theory of the Dirac and electromagnetic fields (quantum electrodynamics), we can start by analyzing a classical theory of these fields. In such a classical field theory, the electron has a spread-out distribution of charge that avoids some of the problems of self-interaction facing point charge models. However, there remains the problem that the electron will experience self-repulsion. This self-repulsion cannot be eliminated within classical field theory without also losing Coulomb interactions between distinct particles. But, electron self-repulsion can be eliminated from quantum electrodynamics in the Coulomb gauge by fully normal-ordering the Coulomb term in the Hamiltonian. After normal-ordering, the Coulomb term contains pieces describing attraction and repulsion between distinct particles and also pieces describing particle creation and annihilation, but no pieces describing self-repulsion.

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Mon May 08 2023 06:54:44 (1 week)

# 16.

Jalloh, Mahmoud (2023) The Π-Theorem as a Guide to Quantity Symmetries and the Argument Against Absolutism. [Preprint]

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Sun May 07 2023 00:22:44 (1 week)

# 17.

Shkliarevsky, Gennady (2023) THE EMPEROR WITH NO CLOTHES: Chomsky Against ChatGPT. [Preprint]

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Sun May 07 2023 00:20:45 (1 week)

# 18.

Wu, Jingyi and Weatherall, James Owen (2023) Between a Stone and a Hausdorff Space. [Preprint]

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Galina Weinstein

Wed May 03 2023 14:52:41 (1 week)

# 19.

In 2003, Simon Baron-Cohen, a world expert on autism, diagnosed Einstein posthumously with Asperger’s syndrome. I think we cannot diagnose a dead person. Historians of science have fiercely objected to this trend of diagnosing deceased scientists by reconstructing from scant evidence, calling these diagnoses myths. Despite the historians’ efforts at demolishing myths, Einstein has been constantly diagnosed with Asperger’s syndrome. I will stick my neck out and suggest in this paper that although historians’ critique of Baron-Cohen and others includes debunking myths, it piggybacks on another myth that uses the following metaphors: a dull and socially adept Einstein who worked at Zurich, Prague, Berlin, and Princeton, an industrious scientist who earned his living through his work as a professor at the university; he had a special gift of friendship and collegiality, and he was deeply embedded in the academic community. These explanations do not make sense from the perspective of Einstein sitting in his office at Princeton, let alone Einstein sitting in the patent office. This perhaps explains the tendency of people to find counterclaims and myths more persuasive than historians’ explanations which seem deeply problematic.

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Jobst Landgrebe, Barry Smith

Wed May 03 2023 14:52:39 (1 week)

# 20.

The view of nature we adopt in the natural attitude is determined by common sense, without which we could not survive. Classical physics is modelled on this common-sense view of nature, and uses mathematics to formalise our natural understanding of the causes and effects we observe in time and space when we select subsystems of nature for modelling. But in modern physics, we do not go beyond the realm of common sense by augmenting our knowledge of what is going on in nature. Rather, we have measurements that we do not understand, so we know nothing about the ontology of what we measure. We help ourselves by using entities from mathematics, which we fully understand ontologically. But we have no ontology of the reality of modern physics; we have only what we can assert mathematically. In this paper, we describe the ontology of classical and modern physics against this background and show how it relates to the ontology of common sense and of mathematics.

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Jose Manuel Rodriguez Caballero

Wed May 03 2023 14:52:38 (1 week)

# 21.

In this essay, we explore the geometric structures involved in the Wolfram model of fundamental physics. Furthermore, we propose some directions of research aiming to get the bosons and fermions out of this framework.

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Michael E. Cuffaro, Stephan Hartmann

Tue May 02 2023 18:47:02 (1 week)

# 22.

It is argued that those who defend the Everett, or `Many Worlds’, interpretation of quantum mechanics should embrace what we call the general quantum theory of open systems (GT) as the proper framework in which to conduct foundational and philosophical investigation in quantum physics. GT is a wider dynamical framework than its alternative, standard quantum theory (ST). This is true even though GT makes no modifications to the quantum formalism. GT rather takes a different view, what we call the open systems view, of the formalism; i.e., in GT the dynamics of systems, whose physical states are fundamentally represented by density operators, are represented as fundamentally open as specified by an in general non-unitary dynamical map. This includes, in principle, the dynamics of the universe as a whole. We argue that the more general dynamics describable in GT can be physically motivated, that there is as much prima facie empirical support for GT as there is for ST, and that GT could be fully in the spirit of the Everett interpretation — that there might, in short, be little reason for an Everettian not to embrace the more general theoretical landscape that GT allows one to explore.

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Sat Apr 29 2023 00:55:58 (2 weeks)

# 23.

Gomes, Henrique and ROVELLI, Carlo (2023) On the analogies between gravitational and electromagnetic radiative energy. [Preprint]

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Sat Apr 29 2023 00:54:04 (2 weeks)

# 24.

Muller, F.A. (2023) Six Measurement Problems of Quantum Mechanics. [Preprint]

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Thu Apr 27 2023 00:57:53 (2 weeks)

# 25.

Gao, Shan (2023) Can the universe be in a mixed state? or did God have a choice in creating the universe? [Preprint]

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Thu Apr 27 2023 00:57:13 (2 weeks)

# 26.

Penchev, Vasil (2023) Hilbert mathematics versus Gödel mathematics III. Hilbert mathematics by itself, and Gödel mathematics versus the physical world within it: both as its particular cases. [Preprint]

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Paolo Molaro

Wed Apr 26 2023 08:57:29 (2 weeks)

# 27.

An intriguing reference to the existence of a self-portrait by Galileo Galilei is contained in the biography of the scientist by Thomas Salusbury dated ca. 1665, of which only one incomplete and inaccessible copy exists. Galileo grew up in a Renaissance atmosphere, acquiring an artistic touch. He was a musician, a writer and also a painter, as reported by Viviani and documented by his watercolours of the Moon and drawings of solar spots. Recently a new portrait with a remarkable similarity to the portraits of Galileo Galilei by Santi di Tito (1601), Domenico Tintoretto (ca. 1604), and Furini (ca. 1612) has been found and examined using sophisticated face recognition techniques. If the identity could be confirmed, other elements, such as the young age of Galileo or the seam in the canvas revealed by infrared and X-ray analysis, may suggest a possible link with the self-portrait mentioned by Salusbury.

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Soumya Chakrabarti

Wed Apr 26 2023 08:57:16 (2 weeks)

# 28.

We show that it is possible to steer clear of a spacetime singularity during gravitational collapse by considering the time-variation of a fundamental coupling, in this case, the fine structure constant {\alpha}. We study a spherical distribution of cold dark matter coexisting with other fluid elements, collapsing under its own gravity. Dark matter is written as a scalar field interacting with electrically charged matter. This leads to a time variation of {\alpha} and as a consequence, a breakdown of local charge conservation within the sphere. The exterior has no such field and therefore, Einstein’s GR and standard equivalence principles remain valid. We derive the lowest possible bound on the collapse of this sphere beyond which there is a bounce and dispersal of most of the accumulated matter. We discuss the critical behavior of the system around this point and show that the bound is connected to a length scale of the order of Planck, introduced in theory for dimensional requirements.

]]>The cosmological frame principle and cosmic acceleration. (arXiv:2304.12733v1 [gr-qc]) |

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by

Spiros Cotsakis, Jose P. Mimoso, John Miritzis

Wed Apr 26 2023 08:57:12 (2 days)

# 7.

We discuss cosmological implications of the frame principle which states that physics is independent of frames. We show that there are frame-independent solutions that are globally stable, suggesting that they represent physically relevant solutions. This result highlights the importance of further investigation into the implications of the cosmological frame principle for cosmological properties that depend on a use of conformal frames.

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Wed Apr 26 2023 00:27:28 (3 days)

# 8.

Smeenk, Chris and Weatherall, James Owen (2023) Dark Energy or Modified Gravity? [Preprint]

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Jonte R. Hance, John Rarity, James Ladyman

Tue Apr 25 2023 13:30:06 (3 days)

# 9.

We investigate four key issues with using a nonzero weak value of the spatial projection operator to infer the past path of an individual quantum particle. First, we note that weak measurements disturb a system, so any approach relying on such a perturbation to determine the location of a quantum particle describes the state of a disturbed system, not that of a hypothetical undisturbed system. Secondly, even assuming no disturbance, there is no reason to associate the non-zero weak value of an operator containing the spatial projection operator with the classical idea of `particle presence’. Thirdly, weak values are only measurable over ensembles, and so to infer properties of individual particles from values of them is problematic. Finally, weak value approaches to the path of a particle do not provide information beyond standard quantum mechanics (and the classical modes supporting the experiment). We know of no experiment with testable consequences that demonstrates a connection between particle presence and weak values.

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Xabier Oianguren-Asua, Carlos F. Destefani, Matteo Villani, David K. Ferry, Xavier Oriols

Tue Apr 25 2023 13:30:05 (3 days)

# 10.

In this chapter, we will take a trip around several hot-spots where Bohmian mechanics and its capacity to describe the microscopic reality, even in the absence of measurements, can be harnessed as computational tools, in order to help in the prediction of phenomenologically accessible information (also useful for the followers of the Copenhagen theory). As a first example, we will see how a Stochastic Schr\”odinger Equation, when used to compute the reduced density matrix of a non-Markovian open quantum system, necessarily seems to employ the Bohmian concept of a conditional wavefunction. We will see that by dressing these conditional wavefunctions with an interpretation, the Bohmian theory can prove to be a useful tool to build general quantum frameworks, like a high-frequency electron transport model. As a second example, we will introduce how a Copenhagen “observable operator” can be derived from numerical properties of the Bohmian trajectories, which within Bohmian mechanics, are well-defined even for an “unmeasured” system. Most importantly in practice, even if these numbers are given no ontological meaning, not only we will be able to simulate (thus, predict and talk about) them, but we will see that they can be operationally determined in a weak value experiment. Therefore, they will be practical numbers to characterize a quantum system irrespective of the followed quantum theory.

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Tue Apr 25 2023 00:37:55 (4 days)

# 11.

Alemañ-Berenguer, Rafael-Andrés (2023) The ontological burden of mathematics and scientific realism. [Preprint]

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Penha Maria Cardozo Dias

Mon Apr 24 2023 10:33:38 (4 days)

# 12.

The association of information with entropy has been argued on plausibility arguments involving the operation of imaginary engines and beings, and it is not a universal theorem. In this paper, a theorem by Charles Bennett on reversible computation is recognized as the much needed theorem. It is proposed a real, non thermal engine, operated by humans. Its operation has stages analogous to the stages in Bennett’s reversible three-tape computer. The engine makes possible to prove two results: (1) the engine operates on two laws, similar to the laws of thermodynamics, which are conditions on the possibility of resetting the engine; (2) entropy is the measure of erased information, and is measured in physical units, which complies with Landauer’s principle. A prototype at work is shown in video.

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R. E. Kastner

Mon Apr 24 2023 10:33:37 (4 days)

# 13.

The traditional, standard approach to quantum theory is to assume that the theory “really” contains only unitary physical dynamics–i.e., that the only physically quantifiable evolution is that given by the time-dependent Schrodinger equation. This leads to two distinct classes of interpretations for the standard theory in its orthodox form: (i) an Everettian-type approach assuming that all mutually exclusive outcomes occur in different “branches” of the universe; or (ii) single-outcome approaches that assume a “projection postulate” (PP) with no accompanying physical account within quantum theory. A contrasting, unorthodox approach is to suggest forms of quantum theory that involve physical non-unitarity; these are called “objective collapse models.” Among these are Penrose’s theory of gravitation-induced collapse and the Transactional Interpretation. The primary focus of this paper is an example demonstrating that standard quantum theory (with or without the projection postulate) can in-principle yield empirically consequential inconsistencies. Thus, it appears that for quantum theory to be viable in a realist sense (as opposed to being an instrumentalist protocol in which inconsistencies are evaded by changing the protocol), it must possess genuine, physical non-unitarity yielding well-defined single outcomes. This leads to the conclusion that objective collapse models should be more seriously considered.

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Iulian D. Toader

Mon Apr 24 2023 10:33:36 (4 days)

# 14.

The paper offers an argument against an intuitive reading of the Stone-von Neumann theorem as a categoricity result, thereby pointing out that, against what is usually taken to be the case, this theorem does not entail any model-theoretical difference between the theories that validate it and those that don’t.

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Volodymyr Ihnatovych

Mon Apr 24 2023 10:33:35 (4 days)

# 15.

The article reveals the error, that in classical thermodynamics leads to the Gibbs paradox. The essence of the error lies in the fact that the entropy of an ideal gas is attributed to additive quantities, but it is not correct. The value of an additive quantity for a whole object is equal to the sum of its values for the parts of the object in any division of the object into parts. The entropy of an ideal gas in classical thermodynamics is expressed by the equation that contains the term Rnln(V/n), where n is the number of moles of gas, V is the volume of gas, R is the universal gas constant, or by equations equivalent to it. As a result, the entropy of an ideal gas is equal to the sum of the entropies of its parts only if the parts of the gas are in different places (separated by an impermeable partition). If the parts of the gas form a mixture, then the sum of the entropies of the parts is not equal to the entropy of the gas. Despite this, the entropy of an ideal gas is considered to be an additive quantity. This gives rise to a series of inexplicable conclusions known as different formulations of the Gibbs paradox.

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Andrea Cavagna; Luca Di Carlo; Irene Giardina; Tomás S. Grigera; Stefania Melillo; Leonardo Parisi; Giulia Pisegna; Mattia Scandolo

Mon Apr 24 2023 08:00:00 (5 days)

# 16.

Nature Physics, Published online: 24 April 2023; doi:10.1038/s41567-023-02028-0

Tests of the predictions of the renormalization group in biological experiments have not yet been decisive. Now, a study on the collective dynamics of insect swarms provides a long-sought match between experiment and theory.

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Mohammadamin Tajik; Ivan Kukuljan; Spyros Sotiriadis; Bernhard Rauer; Thomas Schweigler; Federica Cataldini; João Sabino; Frederik Møller; Philipp Schüttelkopf; Si-Cong Ji; Dries Sels; Eugene Demler; Jörg Schmiedmayer

Mon Apr 24 2023 08:00:00 (5 days)

# 17.

Nature Physics, Published online: 24 April 2023; doi:10.1038/s41567-023-02027-1

The scaling of entanglement entropy and mutual information is key for the understanding of correlated states of matter. An experiment now reports the measurement of von Neumann entropy and mutual information in a quantum field simulator.

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Mon Apr 24 2023 04:39:54 (5 days)

# 18.

Held, Carsten (2023) A Presupposition of Bell’s Theorem. [Preprint]

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Sun Apr 23 2023 00:31:06 (6 days)

# 19.

Meskhidze, Helen and Weatherall, James Owen (2023) Torsion in the Classical Spacetime Context. [Preprint]

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Sun Apr 23 2023 00:28:18 (6 days)

# 20.

Elber-Dorozko, Lotem and Loewenstein, Yonatan (2023) Do retinal neurons also represent somatosensory inputs? On why neuronal responses are not sufficient to determine what neurons do. Cognitive Science.

]]>Confirmation, or Pursuit-worthiness? Lessons from J. J. Sakurai’s 1960 Theory of the Strong Force for the Debate on Non-Empirical Physics. |

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PhilSci-Archive: No conditions. Results ordered -Date Deposited.

Sat Apr 22 2023 01:00:15 (8 hours)

# 1.

Ruiz de Olano, Pablo (2023) Confirmation, or Pursuit-worthiness? Lessons from J. J. Sakurai’s 1960 Theory of the Strong Force for the Debate on Non-Empirical Physics. Studies in History and Philosophy of Modern Physics, 99. pp. 77-88. ISSN 1355-2198

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Cameron C. Yetman

Fri Apr 21 2023 12:04:42 (21 hours)

# 2.

The following annotated bibliography contains a reasonably complete survey of contemporary work in the philosophy of astrophysics. Spanning approximately forty years from the early 1980s to the present day, the bibliography should help researchers entering the field to acquaint themselves with its major texts, while providing an opportunity for philosophers already working on astrophysics to expand their knowledge base and engage with unfamiliar material.

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O. Cristi Stoica, Iulian D. Toader

Fri Apr 21 2023 12:04:41 (21 hours)

# 3.

This paper explains why spacetime singularities do not constitute a breakdown of physical laws, and points out that the difference between the metrics at singularities and those outside of singularities is factual, rather than nomological.

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Aleksander M. Kubicki, Alex May, David Pérez-Garcia,

Fri Apr 21 2023 12:04:40 (21 hours)

# 4.

Within the setting of the AdS/CFT correspondence, we ask about the power of computers in the presence of gravity. We show that there are computations on $n$ qubits which cannot be implemented inside of black holes with entropy less than $O(2^n)$. To establish our claim, we argue computations happening inside the black hole must be implementable in a programmable quantum processor, so long as the inputs and description of the unitary to be run are not too large. We then prove a bound on quantum processors which shows many unitaries cannot be implemented inside the black hole, and further show some of these have short descriptions and act on small systems. These unitaries with short descriptions must be computationally forbidden from happening inside the black hole.

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Dimitrios Psaltis (Georgia Tech)

Fri Apr 21 2023 12:04:39 (21 hours)

# 5.

The Kerr-Newman metric is the unique vacuum solution of the General Relativistic field equations, in which any singularities or spacetime pathologies are hidden behind horizons. They are believed to describe the spacetimes of massive astrophysical objects with no surfaces, which we call black holes. This spacetime, which is defined entirely by the mass, spin, and charge of the black hole, gives rise to a variety of phenomena in the motion of particles and photons outside the horizons that have no Newtonian counterparts. Moreover, the Kerr-Newman spacetime remains remarkably resilient to many attempts in modifying the underlying theory of gravity. The monitoring of stellar orbits around supermassive black holes, the detection of gravitational waves from the coalescence of stellar-mass black holes, and the observation of black-hole shadows in images with horizon-scale resolution, all of which have become possible during the last decade, are offering valuable tools in testing quantitatively the predictions of this remarkable solution to Einstein’s equations.

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Chris Fields, James F. Glazebrook

Fri Apr 21 2023 12:04:38 (21 hours)

# 6.

We study the relationship between assumptions of state separability and both preparation and measurement contextuality, and the relationship of both of these to the frame problem, the problem of predicting what does not change in consequence of an action. We state a quantum analog of the latter and prove its undecidability. We show how contextuality is generically induced in state preparation and measurement by basis choice, thermodynamic exchange, and the imposition of a priori causal models, and how fine-tuning assumptions appear ubiquitously in settings characterized as non-contextual.

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Anna Ijjas

Fri Apr 21 2023 12:04:36 (21 hours)

# 7.

Using the power of numerical relativity, we show that, beginning from generic initial conditions that are far from flat, homogeneous and isotropic and have a large Weyl curvature, a period of slow contraction rapidly drives spacetime towards vanishingly small Weyl curvature as the total energy density grows, thus providing a dynamical mechanism that satisfies the Weyl Curvature Hypothesis. We also demonstrate a tight correlation between the Weyl Curvature Hypothesis and ultralocal behavior for canonical scalar fields with a sufficiently steep negative potential energy density.

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Philipp Strasberg, Teresa E. Reinhard, Joseph Schindler

Fri Apr 21 2023 12:04:29 (21 hours)

# 8.

Within the histories formalism the decoherence functional is a formal tool to investigate the emergence of classicality in isolated quantum systems, yet an explicit evaluation of it from first principles has not been reported. We provide such an evaluation for up to five-time histories based on exact numerical diagonalization. We find emergent classicality for slow and coarse observables of a non-integrable many-body system and extract a finite size scaling law by varying the Hilbert space dimension over four orders of magnitude. Specifically, we conjecture and observe an exponential suppression of quantum effects as a function of the particle number of the system. This suggests a solution to the preferred basis problem of the many worlds interpretation within a minimal theoretical framework, without relying on environmentally induced decoherence, quantum Darwinism, Markov approxmations or ensemble averages. We discuss the implications of our results for the wave function of the Universe, interpretations of quantum mechanics and the arrow(s) of time.

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Daniel Harlow

Fri Apr 21 2023 12:04:24 (21 hours)

# 9.

This chapter gives an overview of the quantum aspects of black holes, focusing on the black hole information problem, the counting of black hole entropy in string theory, and the emergence of spacetime in holography. It is aimed at a broad physics audience, and does not presuppose knowledge of string theory or holography.

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Thu Apr 20 2023 01:33:21 (2 days)

# 10.

Penchev, Vasil (2023) The 2022 Nobel Prize in physics for entanglement and quantum information: the new revolution in quantum mechanics and science. [Preprint]

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Joshua G. Fenwick, Rainer Dick

Wed Apr 19 2023 13:11:45 (2 days)

# 11.

Imposing the Born rule as a fundamental principle of quantum mechanics would require the existence of normalizable wave functions also for relativistic particles. Indeed, the Fourier transforms of normalized k-space amplitudes yield normalized x-space wave packets which reproduce the standard k-space expectation values for energy and momentum from local momentum pseudo-densities. However, in the case of bosonic fields, the wave packets are nonlocally related to the corresponding relativistic quantum fields, and therefore the canonical local energy-momentum densities differ from the pseudo-densities and appear nonlocal in terms of the wave packets. We examine the relation between the canonical energy density, the canonical charge density, the energy pseudo-density, and the Born density for the massless free Klein-Gordon field. We find that those four proxies for particle location are tantalizingly close even in this extremely relativistic case: In spite of their nonlocal mathematical relations, they are mutually local in the sense that their maxima do not deviate beyond a common position uncertainty $\Delta x$. Indeed, they are practically indistinguishable in cases where we would expect a normalized quantum state to produce particle-like position signals, viz. if we are observing quanta with momenta $p\gg\Delta p\ge\hbar/2\Delta x$. We also translate our results to massless Dirac fields. Our results confirm and illustrate that the normalized energy density provides a suitable measure for positions of bosons, whereas normalized charge density provides a suitable measure for fermions.

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Iulian D. Toader

Wed Apr 19 2023 13:11:44 (2 days)

# 12.

This paper provides an algebraic reconstruction of Einstein’s own argument for the incompleteness of quantum mechanics — the one that he thought did not make it into the EPR paper — in order to clarify the assumptions that underlie an understanding of Einstein completeness as categoricity, the sense in which it is a type of descriptive completeness, and some of the various ways in which it has been more often misconstrued.

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Wed Apr 19 2023 05:38:39 (3 days)

# 13.

Horvat, Sebastian and Toader, Iulian Danut (2023) Carnap on Quantum Mechanics. [Preprint]

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Wed Apr 19 2023 05:38:17 (3 days)

# 14.

Horvat, Sebastian and Toader, Iulian Danut (2023) An Alleged Tension between Quantum Logic and Applied Classical Mathematics. [Preprint]

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Wed Apr 19 2023 05:37:51 (3 days)

# 15.

Horvat, Sebastian and Toader, Iulian Danut (2023) Quantum logic and meaning. [Preprint]

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Mathias Van Den Bossche, Philippe Grangier

Tue Apr 18 2023 09:49:17 (3 days)

# 16.

Within the framework of quantum contextuality, we discuss the ideas of extracontextuality and extravalence, that allow one to relate Kochen-Specker’s and Gleason’s theorems. We emphasize that whereas Kochen-Specker’s is essentially a no-go theorem, Gleason’s provides a mathematical justification of Born’s rule. Our extracontextual approach requires however a way to describe the “Heisenberg cut”. Following an article by John von Neumann on infinite tensor products, this can be done by noticing that the usual formalism of quantum mechanics, associated with unitary equivalence of representations, stops working when countable infinities of particles (or degrees of freedom) are encountered. This is because the dimension of the corresponding Hilbert space becomes uncountably infinite, leading to the loss of unitary equivalence, and to sectorisation. Such an intrinsically contextual approach provides a unified mathematical model including both quantum and classical physics, that appear as required incommensurable facets in the description of nature.

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Sebastian Horvat, Iulian Danut Toader

Tue Apr 18 2023 09:49:16 (3 days)

# 17.

This paper gives a formulation of quantum logic in the abstract algebraic setting laid out by Dunn and Hardegree (2001). On this basis, it provides a comparative analysis of viable quantum logical bivalent semantics and their classical counterparts, thereby showing that the truth-functional status of classical and quantum connectives is not as different as usually thought. Then, after pointing out the seemingly forgotten fact that bivalence in quantum logic can be maintained, albeit at the price of truth-functionality, it argues that Hellman (1980) fails to show that this lack of truth-functionality entails a change of meaning between classical and quantum logical connectives. Finally, the paper proposes a meaning-variance argument that fares better on our analysis.

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Tue Apr 18 2023 00:50:34 (4 days)

# 18.

Goyal, Philip (2022) The Role of Reconstruction in the Elucidation of Quantum Theory. [Preprint]

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Leonardo Levinas

Mon Apr 17 2023 12:03:40 (4 days)

# 19.

In the famous thought experiment studied in this article, Galileo attempted to refute the Aristotelian hypothesis that heavier bodies should fall more quickly than lighter ones. After pointing out some inconsistencies in Galileo’s approach, we show, through the design of two alternative but equivalent experiments, that from his imaginary experiment, it is not possible to reach the conclusion that all bodies fall simultaneously. We show why, to explain the result of this type of experience, it is necessary to establish the equivalence between inertial and gravitational masses derived exclusively from experience.

]]>Black Hole Coalescence: Observation and Model Validation |

from PhilSci-Archive: No conditions. Results ordered -Date Deposited.Sat Apr 15 2023 00:44:04 (8 hours)# 1.

Elder, Jamee (2023) Black Hole Coalescence: Observation and Model Validation. [Preprint]

from gr-qc updates on arXiv.org by H. Moradpour, S. Jalalzadeh, Umesh Kumar SharmaFri Apr 14 2023 11:15:25 (22 hours)# 2.

Is thermodynamics consistent with the quantum gravity reconciliation hypothesis [A. G. Cohen et al. Phys. Rev. Lett. 82, 4971 (1999)], which establishes holographic dark energy models? Here, we have attempted to address this issue in the affirmative by concentrating on the first law of thermodynamics.

from Nature Physics by Deanna C. HooperFri Apr 14 2023 08:00:00 (1 day)# 3.

Nature Physics, Published online: 14 April 2023; doi:10.1038/s41567-023-02000-yOn the purpose of physics

from Nature Physics by Silvia ButeraFri Apr 14 2023 08:00:00 (1 day)# 4.

Nature Physics, Published online: 14 April 2023; doi:10.1038/s41567-023-02010-wSingle-photon detection is fundamental in many fields, including quantum technologies. Silvia Butera captures the developments of this detector technology.

from PhilSci-Archive: No conditions. Results ordered -Date Deposited.Thu Apr 13 2023 01:15:51 (2 days)# 5.

Penchev, Vasil (2023) What the Tortoise Said to Achilles: Lewis Carroll’s paradox in terms of Hilbert arithmetic. [Preprint]

from PhilSci-Archive: No conditions. Results ordered -Date Deposited.Tue Apr 11 2023 01:43:14 (4 days)# 6.

Pipa, Francisco (2023) Beyond relationalism in quantum theory. [Preprint]

from PhilSci-Archive: No conditions. Results ordered -Date Deposited.Sun Apr 09 2023 02:00:44 (6 days)# 7.

]]>Childers, Konner (2023) Duality and Categorical Equivalence: A Look at Gauge/Gravity. [Preprint]

On separable states in relativistic quantum field theory. (arXiv:2304.03120v1 [gr-qc]) |

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Ko Sanders

Fri Apr 07 2023 09:03:53 (23 hours)

# 1.

We initiate an investigation into separable, but physically reasonable, states in relativistic quantum field theory. In particular we will consider the minimum amount of energy density needed to ensure the existence of separable states between given spacelike separated regions. This is a first step towards improving our understanding of the balance between entanglement entropy and energy (density), which is of great physical interest in its own right and also in the context of black hole thermodynamics. We will focus concretely on a linear scalar quantum field in a topologically trivial, four-dimensional globally hyperbolic spacetime. For rather general spacelike separated regions $A$ and $B$ we prove the existence of a separable quasi-free Hadamard state. In Minkowski spacetime we provide a tighter construction for massive free scalar fields: given any $R>0$ we construct a quasi-free Hadamard state which is stationary, homogeneous, spatially isotropic and separable between any two regions in an inertial time slice $t=\mathrm{const.}$ all of whose points have a distance $>R$. We also show that the normal ordered energy density of these states can be made $\le 10^{21}\frac{m^4}{(mR)^8}e^{-\frac14mR}$ (in Planck units). To achieve these results we use a rather explicit construction of test-functions $f$ of positive type for which we can get sufficient control on lower bounds on $\hat{f}$.

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Peter Galison, Juliusz Doboszewski, Jamee Elder, Niels C. M. Martens, Abhay Ashtekar, Jonas Enander, Marie Gueguen, Elizabeth A. Kessler, Roberto Lalli, Martin Lesourd, Alexandru Marcoci, Sebastián Murgueitio Ramírez, Priyamvada Natarajan, James Nguyen, Luis Reyes-Galindo, Sophie Ritson, Mike D. Schneider, Emilie Skulberg, Helene Sorgner, Matthew Stanley, Ann C. Thresher, Jeroen Van Dongen, James Owen Weatherall, Jingyi Wu, Adrian Wüthrich

Thu Apr 06 2023 09:15:36 (1 day)

# 2.

This white paper outlines the plans of the History Philosophy Culture Working Group of the Next Generation Event Horizon Telescope Collaboration.

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Kyle Singh, Jenna Van Dyke

Thu Apr 06 2023 09:15:35 (1 day)

# 3.

We investigate structure that describes physical data in gravitational systems that is, to one degree or another, independent of the metric and affine structure. We dub such structure surplus structure and seek to incorporate it into our ontological commitments. An emphasis is placed on those structures which are required to constrain our models motivated by physical data. We look at the fall-offs of the gauge fields in asymptotically flat spacetimes, the computation of entanglement entropies in the AdS/CFT correspondence, and the addition of arbitrary parameters which modify the causal structure of spacetime in Kruskal coordinates. We also present a historical overview of the understanding of singularities in classical gravitation. Primary sources are turned to here. A toy cosmological model is also explored in which global topology is determined by an additional function which we prescribe as a dynamical $\Lambda$. Such surplus structure is classified using the language of intermediaries and positioned within the system of a shifting-scale ontology as introduced in prior work.

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Werner A Hofer

Wed Apr 05 2023 08:54:21 (3 days)

# 4.

I revisit the reply of Bohr to Einstein. Bohr’s assertion that there are no causes in atomic scale systems is, as a closer analysis reveals, not in line with the Copenhagen interpretation since it would contain a statement about reality. What Bohr should have written is that there are no causes in mathematics, which is universally acknowledged. The law of causality requires physical effects to be due to physical causes. For this reason any theoretical model which replaces physical causes by mathematical objects is creationism, that is, it creates physical objects out of mathematical elements. I show that this is the case for most of quantum mechanics.

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Roshan Krishna Kumar

Wed Apr 05 2023 08:00:00 (3 days)

# 5.

Nature Physics, Published online: 05 April 2023; doi:10.1038/s41567-023-02019-1

The production of particle–antiparticle pairs in a vacuum — the Schwinger effect — requires extreme conditions that are out of reach of tabletop experiments. A mesoscopic simulation of this phenomenon has now been carried out in graphene devices.

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Wed Apr 05 2023 06:35:43 (3 days)

# 6.

Wolf, William J. and Thebault, Karim P Y (2023) Explanatory Depth in Primordial Cosmology: A Comparative Study of Inflationary and Bouncing Paradigms.

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Wed Apr 05 2023 06:27:48 (3 days)

# 7.

Broka, Chris A. (2023) Brains as Quantum Mechanical Systems – A New Model. [Preprint]

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Mario Hubert, Charles T. Sebens

Tue Apr 04 2023 12:31:51 (3 days)

# 8.

We argue that the asymmetry between diverging and converging electromagnetic waves is just one of many asymmetries in observed phenomena that can be explained by a past hypothesis and statistical postulate (together assigning probabilities to different states of matter and field in the early universe). The arrow of electromagnetic radiation is thus absorbed into a broader account of temporal asymmetries in nature. We give an accessible introduction to the problem of explaining the arrow of radiation and compare our preferred strategy for explaining the arrow to three alternatives: (i) modifying the laws of electromagnetism by adding a radiation condition requiring that electromagnetic fields always be attributable to past sources, (ii) removing electromagnetic fields and having particles interact directly with one another through retarded action-at-a-distance, (iii) adopting the Wheeler-Feynman approach and having particles interact directly through half-retarded half-advanced action-at-a-distance. In addition to the asymmetry between diverging and converging waves, we also consider the related asymmetry of radiation reaction.

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Ruth E. Kastner

Tue Apr 04 2023 12:31:50 (3 days)

# 9.

There is an extensive philosophical literature on the interrelated issues of identity, individuality, and distinguishability in quantum systems. A key consideration is whether quantum systems are subject to a strong form of individuality termed “haecceity” (from the Latin for “this-ness”). I argue that the traditional, strong form of haecceity does not apply at the quantum level, but that in order to properly account for the need for symmetrization in quantum systems, a weaker kind of haecceity must be involved, which I call “quantum haecceity.” In the process, I also question some generally accepted tenets of the current debate, such as the idea that symmetrization of states for identical quanta must be postulated and reflects permutation invariance. Instead, I note that a perturbative Hamiltonian is required for exchange effects, which suggests that the need for symmetrization arises from specific physical conditions.

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Tue Apr 04 2023 02:06:38 (4 days)

# 10.

Pipa, Francisco (2023) Beyond relationalism in quantum theory. [Preprint]

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Romain Tirole; Stefano Vezzoli; Emanuele Galiffi; Iain Robertson; Dries Maurice; Benjamin Tilmann; Stefan A. Maier; John B. Pendry; Riccardo Sapienza

Mon Apr 03 2023 08:00:00 (5 days)

# 11.

Nature Physics, Published online: 03 April 2023; doi:10.1038/s41567-023-01993-w

A temporal version of Young’s double-slit experiment shows characteristic interference in the frequency domain when light interacts with time slits produced by ultrafast changes in the refractive index of an epsilon-near-zero material.

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Sun Apr 02 2023 10:04:39 (5 days)

# 12.

Struyve, Ward (2023) Scope of the action principle. [Preprint]

]]>Continuous versions of Haack’s puzzles: equilibria, eigen-states and ontologies |

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Sat Apr 01 2023 00:29:17 (9 hours)

# 1.

Stern, Julio Michael (2017) Continuous versions of Haack’s puzzles: equilibria, eigen-states and ontologies. [Preprint]

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Sat Apr 01 2023 00:28:09 (9 hours)

# 2.

Shanahan, Daniel (2023) Protogravity: a quantum-theoretic precursor to gravity. Spacetime Conference 2022. pp. 153-181.

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Takamasa Kanai, Kimihiro Nomura, Daisuke Yoshida

Fri Mar 31 2023 18:53:05 (14 hours)

# 3.

Bousso’s entropy bound is a conjecture that the entropy through a null hypersurface emanating from a two-dimensional surface with a nonpositive expansion is bounded by the area of that two-dimensional surface. We investigate the validity of Bousso’s entropy bound in the spatially flat, homogeneous, and isotropic universe with an adiabatic entropy current. We find that the bound is satisfied in the entire spacetime in which a cutoff time is introduced based on the entropy density and the energy density. Compared to the previously used prescription which puts a cutoff near the curvature singularity, our criterion for introducing the cutoff is applicable even to a nonsingular universe. Our analysis provides an interpretation of the incompleteness implied by the recently proposed singularity theorem based on the entropy bounds.

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Emil J. Martinec

Fri Mar 31 2023 18:53:03 (14 hours)

# 4.

Radiation of conserved charges carried by a black hole is a rare process, whose probability is suppressed by the change in the entropy between the initial and final states. This universal result provides insight into the black hole’s internal structure and dynamics.

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Shinichi Saito

Fri Mar 31 2023 18:53:01 (14 hours)

# 5.

Stokes parameters (${\bf S}$) in Poincar\’e sphere are very useful values to describe the polarisation state of photons. However, the fundamental principle of the nature of polarisation is not completely understood, yet, because we have no concrete consensus how to describe spin of photons, quantum-mechanically. Here, we have considered a monochromatic coherent ray of photons, described by a many-body coherent state, and tried to establish a fundamental basis to describe the spin state of photons, in connection with a classical description based on Stokes parameters. We show that a spinor description of the coherent state is equivalent to Jones vector for polarisation states, and obtain the spin operators (${\bf \hat{S}}$) of all components based on rotators in a $SU(2)$ group theory. Polarisation controllers such as phase-shifters and rotators are also obtained as quantum-mechanical operators to change the phase of the wavefunction for polarisation states. We show that the Stokes parameters are quantum-mechanical average of the obtained spin operators, ${\bf S} = \langle {\bf \hat{S}} \rangle $.

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Thu Mar 30 2023 06:19:07 (2 days)

# 6.

Jacobs, Caspar (2023) Comparativist Theories or Conspiracy Theories: the No Miracles Argument Against Comparativism. [Preprint]

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Wed Mar 29 2023 05:11:38 (3 days)

# 7.

Elder, Jamee (2023) On the “Direct Detection” of Gravitational Waves. [Preprint]

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Wed Mar 29 2023 05:10:28 (3 days)

# 8.

Christian, Joy (2023) Bell’s Theorem Begs the Question. [Preprint]

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Jorge E. Horvath, Rodrigo Rosas Fernandes

Tue Mar 28 2023 09:16:30 (4 days)

# 9.

Quantum Mechanics (QM) stands alone as a (very) successful physical theory, but the meaning of its variables and the status of many quantities in the mathematical formalism is obscure. This unique situation prompted the need for attribution of a physical meaning to the latter, a procedure known as interpretation. On the other hand, the study of QM is usually presented, even to future scientists, within the only framework developed by Bohr and the Copenhagen researchers, known as the Copenhagen interpretation. As a contribution to the understanding and teaching of Quantum Mechanics, aimed to a broader and deeper appreciation of its fundamentals, including contemplating alternatives and updated interpretations for physicists and philosophers interested in the study of exact sciences (through Ontology, Epistemology, Logic or the Theory of Knowledge), we present a set of Conceptual Diagrams elaborated and designed to expose and facilitate the visualization of elements intervening in any interpretation of Quantum Mechanics and apply them to several well-developed cases of the latter.

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Eugene Y. S. Chua

Tue Mar 28 2023 09:16:29 (4 days)

# 10.

Taking the formal analogies between black holes and classical thermodynamics seriously seems to first require that classical thermodynamics applies to relativistic regimes. Yet, by scrutinizing how classical temperature is extended into special relativity, I argue that it falls apart. I examine four consilient procedures for establishing classical temperature – the Carnot process, the thermometer, kinetic theory, and black-body radiation. I show how their relativistic counterparts demonstrate no such consilience in defining relativistic temperature. Hence, classical temperature does not appear to survive a relativistic extension. I suggest two interpretations for this situation – eliminativism akin to simultaneity, or pluralism akin to rotation.

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Eugene Y. S. Chua

Tue Mar 28 2023 09:16:28 (4 days)

# 11.

Conventional wisdom holds that the von Neumann entropy corresponds to thermodynamic entropy, but Hemmo and Shenker (2006) have recently argued against this view by attacking von Neumann (1955) and his argument. I argue that Hemmo and Shenker’s arguments fail due to several misunderstandings: about statistical-mechanical and thermodynamic domains of applicability, about the nature of mixed states, and about the role of approximations in physics. As a result, their arguments fail in all cases: in the single-particle case, the finite particles case, and the infinite particles case.

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Eugene Y. S. Chua, Craig Callender

Tue Mar 28 2023 09:16:27 (4 days)

# 12.

Programs in quantum gravity often claim that time emerges from fundamentally timeless physics. In the semiclassical time program time arises only after approximations are taken. Here we ask what justifies taking these approximations and show that time seems to sneak in when answering this question. This raises the worry that the approach is either unjustified or circular in deriving time from no-time.

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Mike D. Schneider

Tue Mar 28 2023 09:16:26 (4 days)

# 13.

I discuss empty space, as it appears in the physical foundations of relativistic field theories and in the semiclassical study of isolated systems. Of particular interest is the relationship between empirical measurements of the cosmological constant and the question of appropriate representation of empty space by spacetimes, or models of general relativity. Also considered is a speculative move that shows up in one corner of quantum gravity research. In pursuit of holographic quantum cosmology given a positive cosmological constant, there is evidently some freedom available for theoretical physicists to pick between two physically inequivalent spacetime representations of empty space, moving forward: de Sitter spacetime or its ‘elliptic’ cousin.

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Mathias Van Den Bossche, Philippe Grangier

Tue Mar 28 2023 09:16:25 (4 days)

# 14.

Following an article by John von Neumann on infinite tensor products, we develop the idea that the usual formalism of quantum mechanics, associated with unitary equivalence of representations, stops working when countable infinities of particles (or degrees of freedom) are encountered. This is because the dimension of the corresponding Hilbert space becomes uncountably infinite, leading to the loss of unitary equivalence, and to sectorization. By interpreting physically this mathematical fact, we show that it provides a natural way to describe the “Heisenberg cut”, as well as a unified mathematical model including both quantum and classical physics, appearing as required incommensurable facets in the description of nature.

]]>Classical Thought in Newton’s General Scholium. (arXiv:2303.12945v1 [physics.hist-ph]) |

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Karin Verelst

Fri Mar 24 2023 09:25:11 (1 day)

# 1.

Isaac Newton, in popular imagination the Ur-scientist, was an outstanding humanist scholar. His researches on, among others, ancient philosophy, are thorough and appear to be connected to and fit within his larger philosophical and theological agenda. It is therefore relevant to take a closer look at Newton’s intellectual choices, at how and why precisely he would occupy himself with specific text-sources, and how this interest fits into the larger picture of his scientific and intellectual endeavours. In what follows, we shall follow Newton into his study and look over his shoulder while reading compendia and original source-texts in his personal library at Cambridge, meticulously investigating and comparing fragments and commentaries, and carefully keeping track in private notes of how they support his own developing ideas. Indeed, Newton was convinced that precursors to his own insights and discoveries were present already in Antiquity, even before the Greeks, in ancient Egypt, and he puts a lot of time and effort into making the point, especially, and not incidentially, in the period between the first and the second edition of the Principia. A clear understanding of his reading of the classic sources therefore matters to our understanding of its content and gestation process. In what follows we will confine ourselves to the classical legacy, and investigate Newton’s intellectual intercourse with it.

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Joseph P Johnson, Susmita Jana, S. Shankaranarayanan (IIT Bombay)

Fri Mar 24 2023 09:24:58 (1 day)

# 2.

We show that Event Horizon Telescope (EHT) observations allow us to test the fundamental principles of General Relativity (GR). GR is based on the universality of gravity and Einstein’s equivalence principle (EEP). However, EEP is not a basic principle of physics but an empirical fact. Non-Minimal Coupling (NMC) of electromagnetic fields violates EEP, and their effects manifest in the strong-gravity regime. Hence, EHT provides an opportunity to test NMC in the strong-gravity regime. We show that, to the leading order in the spin parameter, NMC of the electromagnetic field modifies the black hole image in two ways: First, for one polarization mode, the horizon casts a shadow of radius \emph{greater than} $\sqrt{27} GM/c^2$ on the image of the source. For the other polarization mode, it is \emph{smaller than} $\sqrt{27} GM/c^2$. Second, the brightness and the position of the lensing ring are affected by the non-minimal coupling. The lensing ring is more prominent for one polarization mode than the other. Finally, we discuss the constraints on the NMC constant from future ngEHT observations.

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Thu Mar 23 2023 01:02:56 (2 days)

# 3.

Broka, Chris A. (2023) Brains as Quantum Mechanical Systems – A New Model. [Preprint]

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Stephen Boughn

Wed Mar 22 2023 09:35:31 (3 days)

# 4.

According to physicist David Mermin, the science wars was a series of exchanges between scientists and “sociologists, historians, and literary critics” whom the scientists thought to be “ludicrously ignorant of science, making all kinds of nonsensical pronouncements.” The science wars peaked in 1996 with the publication of a hoax article by physicist Alan Sokal in a cultural studies journal and then seemed mercifully to die away by the end of the 1990’s. I recently noticed, however, that the kerfuffle has persisted. This motivated me to pen this essay and point out the silliness of the entire affair.

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Wed Mar 22 2023 05:14:32 (3 days)

# 5.

Wolf, William J. and Thebault, Karim P Y (2023) Explanatory Depth in Primordial Cosmology: A Comparative Study of Inflationary and Bouncing Paradigms. The British Journal for the Philosophy of Science.

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Tue Mar 21 2023 01:21:27 (4 days)

# 6.

Adlam, Emily (2023) Are Entropy Bounds Epistemic? [Preprint]

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Mon Mar 20 2023 01:56:31 (5 days)

# 7.

Deng, Natalja (2023) Commentary: “Physical Time within Human Time” and “Bridging the Neuroscience and Physics of Time”. [Preprint]

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Sun Mar 19 2023 01:12:41 (6 days)

# 8.

Halvorson, Hans (2023) Invariance and ontology in relativistic physics. [Preprint]

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Sun Mar 19 2023 01:08:25 (6 days)

# 9.

Lyons, Tony (2023) Relational space-time and de Broglie waves. [Preprint]

**arXiv:2303.04787** (quant-ph)[Submitted on 8 Mar 2023]

**Single-pair measurement of the Bell parameter**

Salvatore Virzì, Enrico Rebufello, Francesco Atzori, Alessio Avella, Fabrizio Piacentini, Rudi Lussana, Iris Cusini, Francesca Madonini, Federica Villa, Marco Gramegna, Eliahu Cohen, Ivo Pietro Degiovanni, Marco Genovese

Bell inequalities are one of the cornerstones of quantum foundations, and fundamental tools for quantum technologies. Recently, the scientific community worldwide has put a lot of effort towards them, which culminated with loophole-free experiments. Nonetheless, none of the experimental tests so far was able to extract information on the full inequality from each entangled pair, since the wave function collapse forbids performing, on the same quantum state, all the measurements needed for evaluating the entire Bell parameter. We present here the first single-pair Bell inequality test, able to obtain a Bell parameter value for every entangled pair detected. This is made possible by exploiting sequential weak measurements, allowing to measure non-commuting observables in sequence on the same state, on each entangled particle. Such an approach not only grants unprecedented measurement capability, but also removes the need to choose between different measurement bases, intrinsically eliminating the freedom-of-choice loophole and stretching the concept of counterfactual-definiteness (since it allows measuring in the otherwise not-chosen bases). We also demonstrate how, after the Bell parameter measurement, the pair under test still presents a noteworthy amount of entanglement, providing evidence of the absence of (complete) wave function collapse and allowing to exploit this quantum resource for further protocols.

]]>A preliminary hidden variables matrix mechanics treatment of the harmonic oscillator has been previously presented based on classical endogenous periodic motion. This work extends to incorporating the model into the mathematics of matrix mechanics. Although initially motivated by EPR-Bell analysis, the proposed model is based on re-examining the physical assumptions of Heisenberg and Born. All assumptions are maintained except for Bohr’s state-to-state instantaneous transition which has been experimentally invalidated, and Heisenberg’s non-path postulate which is replaced by classical endogenous periodic paths. Matrix elements of standard matrix mechanics are modified to replace transition amplitudes by transition paths. The redefined elements generate eigenvalues-eigenstates which then characterise eigenpaths. Since the endogenous motion averages out over a cycle it is unseen by the wave function. Nevertheless, mathematical equivalence with position and momentum non-commutation in Schrodinger operators is preserved. The modified matrix mechanics is shown to be mathematically equivalent to that of Born-Jordan reproducing all standard results. Generic quantum equations of motion are obtained following the quantization procedures of Born-Jordan and Dirac’s Poisson Bracket equation. These new relations meet the benchmark criteria of reproducing conservation of energy and the quantum frequency condition. Since the endogenous paths are ontologically classical no radical metaphysical interpretations are needed for spatial-temporal movement. Quantum randomness is not explained by the proposed model but is attributed to endogenous structures of quantum matter.

]]>