Weekly Papers on Quantum Foundations (50)

Directed Temporal Asymmetry from Scale Invariant Dynamics: Is the Problem of Time’s Arrow Solved? 

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

Sat Dec 10 2022 03:10:52 (7 hours)

# 1.

Ryder, Dominic J. (2022) Directed Temporal Asymmetry from Scale Invariant Dynamics: Is the Problem of Time’s Arrow Solved? [Preprint]

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What is Nonclassical about Uncertainty Relations? 

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

 by 

Lorenzo Catani, Matthew Leifer, Giovanni Scala, David Schmid, and Robert W. Spekkens

Fri Dec 09 2022 18:00:00 (17 hours)

# 2.

Author(s): Lorenzo Catani, Matthew Leifer, Giovanni Scala, David Schmid, and Robert W. Spekkens

Uncertainty relations express limits on the extent to which the outcomes of distinct measurements on a single state can be made jointly predictable. The existence of nontrivial uncertainty relations in quantum theory is generally considered to be a way in which it entails a departure from the classi…

[Phys. Rev. Lett. 129, 240401] Published Fri Dec 09, 2022

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Contemporary Philosophical Perspectives on the Cosmological Constant. (arXiv:2212.04335v1 [physics.hist-ph]) 

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physics.hist-ph updates on arXiv.org

 by 

Adam Koberinski, Bridget Falck, Chris Smeenk

Fri Dec 09 2022 09:58:46 (1 day)

# 3.

The (re)introduction of $\Lambda$ into cosmology has spurred debates that touch on central questions in philosophy of science, as well as the foundations of general relativity and particle physics. We provide a systematic assessment of the often implicit philosophical assumptions guiding the methodology of precision cosmology in relation to dark energy. We start by briefly introducing a recent account of scientific progress in terms of risky and constrained lines of inquiry. This allows us to contrast aspects of $\Lambda$ that make it relevantly different from other theoretical entities in science, such as its remoteness from direct observation or manipulability. We lay out a classification for possible ways to explain apparent accelerated expansion but conclude that these conceptually clear distinctions may blur heavily in practice. Finally, we consider the important role played in cosmology by critical tests of background assumptions, approximation techniques, and core principles, arguing that the weak anthropic principle fits into this category. We argue that some core typicality assumptions — like the Copernican principle and the cosmological principle — are necessary though not provable, while others — like the strong anthropic principle and appeals to naturalness or probability in the multiverse — are not similarly justifiable.

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Nikola Tesla’s Inventions — Myth or Reality?. (arXiv:2212.04440v1 [physics.pop-ph]) 

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physics.hist-ph updates on arXiv.org

 by 

Valery G. Rousseau

Fri Dec 09 2022 09:58:45 (1 day)

# 4.

Nikola Tesla is often presented by his adepts as the “unjustly forgotten genius”, without who our current technology wouldn’t exist. In this paper, we analyze some popular statements made by Tesla’s adepts, mostly about inventions that they attribute to him, and determine whether they are myth or reality.

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Quantum version of the Euler’s problem: a geometric perspective. (arXiv:2212.03903v1 [quant-ph]) 

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quant-ph updates on arXiv.org

 by 

Karol Zyczkowski

Fri Dec 09 2022 09:58:39 (1 day)

# 5.

The classical combinatorial problem of $36$ officers has no solution, as there are no Graeco-Latin squares of order six. The situation changes if one works in a quantum setup and allows for superpositions of classical objects and admits entangled states. We analyze the recently found solution to the quantum version of the Euler’s problem from a geometric point of view. The notion of a non-displaceable manifold embedded in a larger space is recalled. This property implies that any two copies of such a manifold, like two great circles on a sphere, do intersect. Existence of a quantum Graeco-Latin square of size six, equivalent to a maximally entangled state of four subsystems with d=6 levels each, implies that three copies of the manifold U(36)/U(1) of maximally entangled states of the $36\times 36$ system, embedded in the complex projective space ${C}P^{36\times 36 -1}$, do intersect simultaneously at a certain point.

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Reversing the Arrow of Time. (arXiv:2212.03489v1 [physics.hist-ph]) 

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physics.hist-ph updates on arXiv.org

 by 

Bryan W Roberts

Thu Dec 08 2022 10:28:36 (2 days)

# 6.

The arrow of time refers to the curious asymmetry that distinguishes the future from the past. Reversing the Arrow of Time argues that there is an intimate link between the symmetries of ‘time itself’ and time reversal symmetry in physical theories, which has wide-ranging implications for both physics and its philosophy. This link helps to clarify how we can learn about the symmetries of our world; how to understand the relationship between symmetries and what is real, and how to overcome pervasive illusions about the direction of time. Roberts explains the significance of time reversal in a way that intertwines physics and philosophy, to establish what the arrow of time means and how we can come to know it. This book is both mathematically and philosophically rigorous yet remains accessible to advanced undergraduates in physics and philosophy of physics.

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A comment on: Adam R. Brown and Leonard Susskind’s paper “A holographic wormhole traversed in a quantum computer”. (arXiv:2212.03568v1 [physics.hist-ph]) 

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physics.hist-ph updates on arXiv.org

 by 

Galina Weinstein

Thu Dec 08 2022 10:28:35 (2 days)

# 7.

Adam Brown and Leonard Susskind write in their new paper, “A holographic wormhole traversed in a quantum computer”: “The idea of a wormhole dates back to 1935, when Albert Einstein and his collaborator, Nathan Rosen, studied black holes in the context of Einstein’s general theory of relativity. […] In the same year, Einstein and Rosen wrote another paper, this time in collaboration with Boris Podolsky. […] At the time, these two ideas – wormholes and entanglement – were considered to be entirely separate”. I will show in this comment that for Einstein, these two ideas were not “entirely separate”.

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First-Class Constraints, Gauge Transformations, de-Ockhamization, and Triviality: Replies to Critics, Or, How (Not) to Get a Gauge Transformation from a Second-Class Primary Constraint. (arXiv:2212.02944v1 [physics.hist-ph]) 

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physics.hist-ph updates on arXiv.org

 by 

J. Brian Pitts

Wed Dec 07 2022 09:58:54 (3 days)

# 8.

Recently two pairs of authors have aimed to vindicate the longstanding conventional claim that a first-class constraint generates a gauge transformation in typical gauge theories such as electromagnetism, Yang-Mills and General Relativity, in response to the Lagrangian-equivalent reforming tradition, in particular Pitts, _Annals of Physics_ 2014. Both pairs emphasize the coherence of the extended Hamiltonian formalism against what they take to be core ideas in Pitts 2014, but both overlook Pitts 2014’s sensitivity to ways that one might rescue the claim in question, including an additive redefinition of the electrostatic potential. Hence the bulk of the paper is best interpreted as arguing that the longstanding claim about separate first-class constraints is _either false or trivial_ — de-Ockhamization (using more when less suffices by splitting one quantity into the sum of two) being trivial. Unfortunately section 9 of Pitts 2014, a primarily verbal argument that plays no role in other works, is refuted.

Pooley and Wallace’s inverse Legendre transformation to de-Ockhamized electromagnetism with an additively redefined electrostatic potential, however, opens the door to a precisely analogous calculation introducing a photon mass, which shows that a _second-class primary_ constraint generates a gauge transformation in the exactly same sense — a reductio ad absurdum of the claim that a first-class constraint generates a gauge transformation and a second-class constraint does not. Gauge freedom by de-Ockhamization does not require any constraints at all, first-class or second-class, because any dynamical variable in any Lagrangian can be de-Ockhamized into exhibiting trivial additive artificial gauge freedom by splitting one quantity into the sum of two. Physically interesting gauge freedom, however, is typically generated by a tuned sum of first-class constraints.

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Quantum spatial superpositions and the possibility of superluminal signaling 

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

Wed Dec 07 2022 02:50:54 (3 days)

# 9.

Ávila, Partricio and Okon, Elias and Sudarsky, Daniel and Wiedemann, Martín (2022) Quantum spatial superpositions and the possibility of superluminal signaling. [Preprint]

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The split of the century 

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Nature Physics

Tue Dec 06 2022 08:00:00 (4 days)

# 10.

Nature Physics, Published online: 06 December 2022; doi:10.1038/s41567-022-01886-4

This month, we celebrate the hundredth anniversary of the iconic experiment by Otto Stern and Walther Gerlach — a milestone in the development of quantum mechanics.

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Can the ontology of Bohmian mechanics consists only in particles? The PBR theorem says no 

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

Tue Dec 06 2022 03:31:06 (4 days)

# 11.

Gao, Shan (2022) Can the ontology of Bohmian mechanics consists only in particles? The PBR theorem says no. [Preprint]

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