# Weekly Papers on Quantum Foundations (43)

This is a list of this week’s papers on quantum foundations published in various journals or uploaded to preprint servers such as arxiv.org and PhilSci Archive.

Holographic Theory of Gravity and Cosmology. (arXiv:1610.06236v1 [gr-qc])

hep-th updates on arXiv.org

on 2016-10-22 4:15am GMT

Authors: Y. Jack Ng

According to the holographic principle, the maximum amount of information stored in a region of space scales as the area of its two-dimensional surface, like a hologram. We show that the holographic principle can be understood heuristically as originated from quantum fluctuations of spacetime. Applied to cosmology, this consideration leads to a dynamical cosmological constant $\Lambda$ of the observed magnitude, in agreement with the result obtained for the present and recent cosmic eras, by using unimodular gravity and causal-set theory. By generalizing the concept of entropic gravity, we find a critical acceleration parameter related to $\Lambda$ in galactic dynamics, and we construct a phenomenological model of dark matter which we call “modified dark matter” (MDM). We provide successful observational tests of MDM at both the galactic and cluster scales. We also discuss the possibility that the quanta of both dark energy and dark matter obey the quantum Boltzmann statistics or infinite statistics as described by a curious average of the bosonic and fermionic algebras.

Reconciling axiomatic quantum field theory with cutoff-dependent particle physics

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

on 2016-10-21 7:24pm GMT

Koberinski, Adam (2016) Reconciling axiomatic quantum field theory with cutoff-dependent particle physics. In: UNSPECIFIED.

Fundamental and emergent geometry in Newtonian physics

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

on 2016-10-21 7:23pm GMT

Wallace, David (2016) Fundamental and emergent geometry in Newtonian physics. [Preprint]

Eight Myths about Scientific Realism

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

on 2016-10-21 7:21pm GMT

Cordero, Alberto (2016) Eight Myths about Scientific Realism. In: UNSPECIFIED.

Quantum discord as a tool for comparing collapse models and decoherence

ScienceDirect Publication: Physics Letters A

on 2016-10-21 3:12pm GMT

Publication date: 25 November 2016
Source:Physics Letters A, Volume 380, Issue 45
Author(s): Shreya Banerjee, Sayantani Bera, Tejinder P. Singh
The quantum to classical transition maybe caused by decoherence or by dynamical collapse of the wave-function. We propose quantum discord as a tool, (1) for comparing and contrasting the role of a collapse model (Continuous Spontaneous Localisation) and various sources of decoherence (environmental and fundamental), (2) for detecting collapse model and fundamental decoherence for an experimentally demonstrated macroscopic entanglement. We discuss the experimental times which will lead to the detection of either Continuous Spontaneous Localisation or fundamental decoherence. We further put bounds on the collapse parameters from this experiment for quantum discord.

Origin of chaos in 3-d Bohmian trajectories

ScienceDirect Publication: Physics Letters A

on 2016-10-21 3:12pm GMT

Publication date: 25 November 2016
Source:Physics Letters A, Volume 380, Issue 45
Author(s): Athanasios C. Tzemos, George Contopoulos, Christos Efthymiopoulos
We study the 3-d Bohmian trajectories of a quantum system of three harmonic oscillators. We focus on the mechanism responsible for the generation of chaotic trajectories. We demonstrate the existence of a 3-d analogue of the mechanism found in earlier studies of 2-d systems [1,2], based on moving 2-d ‘nodal point–X-point complexes’. In the 3-d case, we observe a foliation of nodal point–X-point complexes, forming a ‘3-d structure of nodal and X-points’. Chaos is generated when the Bohmian trajectories are scattered at one or more close encounters with such a structure.

A conjecture concerning determinism, reduction, and measurement in quantum mechanics. (arXiv:1204.0614v5 [quant-ph] CROSS LISTED)

physics.hist-ph updates on arXiv.org

on 2016-10-21 12:37am GMT

Authors: Arthur Jabs

It is shown that it is possible to introduce determinism into quantum mechanics by tracing the probabilities in the Born rules back to pseudorandomness in the absolute phase constants of the wave functions. Each wave function is conceived to contain an individual phase factor exp(i{\alpha}). In an ensemble of systems the phase constants {\alpha} are taken to be pseudorandom numbers. A reduction process (collapse), independent of any measurement, is conceived to be a spatial contraction of two wavepackets when they meet and satisfy a certain criterion. The criterion depends on the phase constants of both wavepackets. The measurement apparatus fans out the incoming wavepacket into spatially separated eigenpackets of the observable and a reduction associates the point of contraction with an eigenvalue of the observable. The theory is nonlocal and contextual.

Which-way double slit experiments and Born rule violation. (arXiv:1610.06401v1 [quant-ph])

quant-ph updates on arXiv.org

on 2016-10-21 12:37am GMT

Authors: James Q. Quach

The double-slit experiment is used as the archetypal interference experiment to dramatically demonstrate the quantum weirdness of wave-particle duality. It is a long-held assumption that whether which-way detectors are placed at one slit or both will yield the same results, rendering the second detector redundant. Here we show that the presence of the second detector can have measurable effects on the interference pattern, violating this assumption. We show that this effect forms the basis for a new measure of Born rule violation which is correct to all orders. It opens new experimental opportunities for the accurate testing of the Born rule.

Detecting macroscopic quantum coherence with a cavity optomechanical system. (arXiv:1610.06260v1 [quant-ph])

quant-ph updates on arXiv.org

on 2016-10-21 12:37am GMT

Authors: Qiang ZhengJianwei XuYao YaoYong Li

The rigorous resource framework of quantum coherence has been set up recently and excited a wide variety of interests. Here we show that a quantum cavity optomechanical system, as an emerging platform, can behave with a certain value of quantum coherence at a macroscopic scale. We also find that the difference between the total optomechanical coherence and the sum of the optical and the mechanical coherence just equals their mutual information. Motivated by the detection of the optomechanical entanglement, an experimentally feasible scheme to probe the optomechanical coherence is proposed.

Measuring Incompatible Observables by Exploiting Sequential Weak Values

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

on 2016-10-20 2:00pm GMT

Author(s): F. Piacentini, A. Avella, M. P. Levi, M. Gramegna, G. Brida, I. P. Degiovanni, E. Cohen, R. Lussana, F. Villa, A. Tosi, F. Zappa, and M. Genovese

One of the most intriguing aspects of quantum mechanics is the impossibility of measuring at the same time observables corresponding to noncommuting operators, because of quantum uncertainty. This impossibility can be partially relaxed when considering joint or sequential weak value evaluation. Inde…

[Phys. Rev. Lett. 117, 170402] Published Thu Oct 20, 2016

Special relativity in a discrete quantum universe

PRA: Fundamental concepts

on 2016-10-20 2:00pm GMT

Author(s): Alessandro Bisio, Giacomo Mauro D’Ariano, and Paolo Perinotti

The hypothesis of a discrete fabric of the universe, the “Planck scale,” is always on stage since it solves mathematical and conceptual problems in the infinitely small. However, it clashes with special relativity, which is designed for the continuum. Here, we show how the clash can be overcome with…

[Phys. Rev. A 94, 042120] Published Thu Oct 20, 2016

Experimental Test of Compatibility-Loophole-Free Contextuality with Spatially Separated Entangled Qutrits

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

on 2016-10-20 2:00pm GMT

Author(s): Xiao-Min Hu, Jiang-Shan Chen, Bi-Heng Liu, Yu Guo, Yun-Feng Huang, Zong-Quan Zhou, Yong-Jian Han, Chuan-Feng Li, and Guang-Can Guo

The physical impact and the testability of the Kochen-Specker (KS) theorem is debated because of the fact that perfect compatibility in a single quantum system cannot be achieved in practical experiments with finite precision. Here, we follow the proposal of A. Cabello and M. T. Cunha [Phys. Rev. Le…

[Phys. Rev. Lett. 117, 170403] Published Thu Oct 20, 2016

It’s a Matter of Principle. Scientific Explanation in Information-Theoretic Reconstructions of Quantum Theory

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

on 2016-10-20 2:53am GMT

Felline, Laura (2016) It’s a Matter of Principle. Scientific Explanation in Information-Theoretic Reconstructions of Quantum Theory. [Preprint]

About a “Nonlocal” Local Model Considered by L. Vervoort, and the Necessity to Distinguish Locality from Einstein Locality

Latest Results for Foundations of Physics

on 2016-10-20 12:00am GMT

Abstract

L. Vervoort claims to have found a model which “can violate the Bell inequality and reproduce the quantum statistics, even if it is based on local dynamics only”. This claim is false. The proposed model contains global elements. The physics behind the model is local, but would not allow the explanation of violations of Bell inequalities for space-like separated events, if superluminal causal influences are forbidden. To use it for this purpose, one has to introduce a preferred frame where information can be send faster than light. As a cause of the misunderstanding we identify the unfortunate convention to use “local” as a synonym for Einstein-local, so that theories which are local in every physically relevant sense have to be named “non-local”, and argue that this convention should be abandoned.

Lindblad decoherence in atomic clocks

PRA: Fundamental concepts

on 2016-10-19 2:00pm GMT

Author(s): Steven Weinberg

It is shown how possible corrections to ordinary quantum mechanics described by the Lindblad equation might be detected by exploiting the great precision of atomic clocks.

[Phys. Rev. A 94, 042117] Published Wed Oct 19, 2016

Averaged Null Energy Condition from Causality. (arXiv:1610.05308v1 [hep-th])

hep-th updates on arXiv.org

on 2016-10-19 1:58am GMT

Unitary, Lorentz-invariant quantum field theories in flat spacetime obey microcausality: commutators vanish at spacelike separation. For interacting theories in more than two dimensions, we show that this implies that the averaged null energy, $\int du T_{uu}$, must be positive. This non-local operator appears in the operator product expansion of local operators in the lightcone limit, and therefore contributes to $n$-point functions. We derive a sum rule that isolates this contribution and is manifestly positive. The argument also applies to certain higher spin operators other than the stress tensor, generating an infinite family of new constraints of the form $\int du X_{uuu\cdots u} \geq 0$. These lead to new inequalities for the coupling constants of spinning operators in conformal field theory, which include as special cases (but are generally stronger than) the existing constraints from the lightcone bootstrap, deep inelastic scattering, conformal collider methods, and relative entropy. We also comment on the relation to the recent derivation of the averaged null energy condition from relative entropy, and suggest a more general connection between causality and information-theoretic inequalities in QFT.

What Can We Learn From Analogue Experiments?

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

on 2016-10-17 7:31pm GMT

Thebault, Karim P Y (2016) What Can We Learn From Analogue Experiments? [Preprint]

Why protective measurement implies the reality of the wave function: Further consolidation

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

on 2016-10-16 6:36pm GMT

Gao, Shan (2016) Why protective measurement implies the reality of the wave function: Further consolidation. In: UNSPECIFIED.

Psi-Epistemic Quantum Cosmology?

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

on 2016-10-16 6:29pm GMT

Evans, Peter W. and Gryb, Sean and Thebault, Karim P Y (2016) Psi-Epistemic Quantum Cosmology? [Preprint]