# Weekly Papers on Quantum Foundations (9)

Witnessing the survival of time-energy entanglement through biological tissue and scattering media. (arXiv:2102.12907v1 [quant-ph])

We demonstrate the preservation of time-energy entanglement of near-IR photons through thick biological media ($\leq$1.55 mm) and tissue ($\leq$ 235 $\mu$m) at room temperature. Using a Franson-type interferometer, we demonstrate interferometric contrast of over 0.9 in skim milk, 2% milk, and chicken tissue. This work supports the many proposed opportunities for nonclassical light in biological imaging and analyses from sub-shot noise measurements to entanglement-enhanced fluorescence imaging, clearly indicating that the entanglement characteristics of photons can be maintained even after propagation through thick, turbid biological samples.

Quantum Contextuality. (arXiv:2102.13036v1 [quant-ph])

A central result in the foundations of quantum mechanics is the Kochen-Specker theorem. In short, it states that quantum mechanics is in conflict with classical models in which the result of a measurement does not depend on which other compatible measurements are jointly performed. Here, compatible measurements are those that can be performed simultaneously or in any order without disturbance. This conflict is generically called quantum contextuality. In this article, we present an introduction to this subject and its current status. We review several proofs of the Kochen-Specker theorem and different notions of contextuality. We explain how to experimentally test some of these notions and discuss connections between contextuality and nonlocality or graph theory. Finally, we review some applications of contextuality in quantum information processing.

All states are universal catalysts in quantum thermodynamics. (arXiv:2006.16290v2 [quant-ph] UPDATED)

Quantum catalysis is a fascinating concept which demonstrates that certain transformations can only become possible when given access to a specific resource that has to be returned unaffected. It was first discovered in the context of entanglement theory and since then applied in a number of resource-theoretic frameworks, including quantum thermodynamics. Although in that case the necessary (and sometimes also sufficient) conditions on the existence of a catalyst are known, almost nothing is known about the precise form of the catalyst state required by the transformation. In particular, it is not clear whether it has to have some special properties or be finely tuned to the desired transformation. In this work we describe a surprising property of multi-copy states: we show that in resource theories governed by majorization all resourceful states are catalysts for all allowed transformations. In quantum thermodynamics this means that the so-called “second laws of thermodynamics” do not require a fine-tuned catalyst but rather any state, given sufficiently many copies, can serve as a useful catalyst. These analytic results are accompanied by several numerical investigations that indicate that neither a multi-copy form nor a very large dimension catalyst are required to activate most allowed transformations catalytically.

Direct measurements of neutrino mass

Publication date: Available online 25 February 2021

Source: Physics Reports

Author(s): Joseph A. Formaggio, André Luiz C. de Gouvêa, R.G. Hamish Robertson

A large-scale heuristic modification of Newtonian gravity as alternative approach to the dark energy and dark matter. (arXiv:2102.12573v1 [gr-qc])

Authors: Nelson Falcon

The peculiarities of the inverse square law of Newtonian gravity in standard Big Bang Cosmology are discussed. It is shown that the incorporation of an additive term to Newtonian gravitation, as the inverse Yukawa-like field, allows remove the incompatibility between the flatness of the Universe and the density of matter in the Friedmann equation, provides a new approach for dark energy, and enable theoretical deduce the Hubble-Lemaitre’s law. The source of this inverse Yukawa-like field is the ordinary baryonic matter and represents the large-scale contribution of gravity in accordance with the Mach’s principle. It’s heuristically build from a specular reflection of the Yukawa potential, in agreement with astronomical and laboratory observables, result null in the inner solar system, weakly attractive in ranges of interstellar distances, very attractive in distance ranges comparable to the clusters of galaxies and repulsive in cosmic scales. Its implications in the missing mass of Zwicky, Virial Theorem, Kepler’s Third Law in Globular Clusters, rotations curves of galaxies, gravitational redshift and the Jean’s mass are discussed. The inclusion of the inverse Yukawa-like field in Newtonian gravitation predicts a graviton mass of at least 10-64 kg and could be an alternative to the paradigm of non-baryonic dark matter concomitant with the observables of the Big Bang.

Comment on “Constraints on Low-Energy Effective Theories from Weak Cosmic Censorship”. (arXiv:2101.10172v2 [gr-qc] UPDATED)

Authors: Jie JiangAofei SangMing Zhang

Recently, it was argued in [Phys. Rev. Lett. {\bf126}, 031102 (2021)] that the WCCC can serve as a constraint to high-order effective field theories. However, we find there exists a key error in their approximate black hole solution. After correcting it, their calculation cannot show the ability of WCCC to constrain the gravitational theories.

Trans-Planckian Censorship Conjecture and Early Universe Cosmology. (arXiv:2102.09641v2 [hep-th] UPDATED)

Authors: Robert Brandenberger (McGill University)

I review the “Trans-Planckian Censorship Conjecture” (TCC) and its implications for cosmology, in particular for the inflationary universe scenario. Whereas the inflationary scenario is tightly constrained by the TCC, alternative early universe scenarios are not restricted.

Thermodynamics of Gambling Demons

Author(s): Gonzalo Manzano, Diego Subero, Olivier Maillet, Rosario Fazio, Jukka P. Pekola, and Édgar Roldán

In a new version of Maxwell’s demon, the tiny being plays the role of a gambler who knows when to quit.

[Phys. Rev. Lett. 126, 080603] Published Fri Feb 26, 2021

Essay Review of Tanya and Jeffrey Bub’s Totally Random: Why Nobody Understands Quantum Mechanics: A Serious Comic on Entanglement

Cuffaro, Michael E. and Doyle, Emerson P. (2020) Essay Review of Tanya and Jeffrey Bub’s Totally Random: Why Nobody Understands Quantum Mechanics: A Serious Comic on Entanglement. [Preprint]

A pragmatic approach to the ontology of models

Abstract

What are scientific models? Philosophers of science have been trying to answer this question during the last three decades by putting forward a number of different proposals. Some say that models are best understood as abstract Platonic objects or fictional entities akin to Sherlock Holmes, while others focus on their mathematical nature and see them as set theoretical structures. Although each account has its own strengths in offering various insights on the nature of models, several objections have been raised against these views which still remain unanswered, making the debate on the ontology of models seem unresolvable. The primary aim of this paper is to show that a large part of these difficulties stems from an inappropriate reading of the main question on the ontology of models as a purely metaphysical question. Building on Carnap, it is argued that the question of the ontology of scientific models is either (i) an internal theoretical question within an already accepted linguistic framework or (ii) an external practical question regarding the choice of the most appropriate form of language in order to describe and explain the practice of scientific modelling. The main implication of this view is that the question of the ontology of models becomes a means of probing other related questions regarding the overall practice of scientific modelling, such as questions on the capacity of models to provide knowledge and the relation of models with background theories.

Non-equilibrium quantum dynamics and formation of the Bose polaron

Nature Physics, Published online: 25 February 2021; doi:10.1038/s41567-021-01184-5

Quantum impurities immersed in a bosonic environment can evolve into polaronic quasiparticles, so-called polarons. Interferometric measurement reveals this transition, which involves three different regimes dominated by few-body and many-body dynamics.

I could do that in my sleep: skilled performance in dreams

Abstract

The experience of skilled action occurs in dreams if we take dream reports at face value. However, what these reports indicate requires nuanced analysis. It is uncertain what it means to perform any action in a dream whatsoever. If skilled actions do occur in dreams, this has important implications for both theory of action and theory of dreaming. Here, it is argued that since some dreams generate a convincing, hallucinated world where we have virtual bodies that interact with virtual objects, there is a sense in which we can perform virtual actions. Further, we can also perform skilfully, although not all apparent skilful performance is as it seems. Since the dream world is generated by the dreamer’s own mind, it can be difficult to determine whether the dream world simply allows goals to be achieved without the abilities that would be required in a similar waking scenario. Because of this, individual dream reports alone are insufficient to determine what skills are demonstrated in a particular dream. However, taken with evidence from REM sleep behaviour disorder, incompetent dreams, lucid dreams and motor-skill practise, it is likely that skilled virtual dream performance at times involves both opportunity for virtual behaviour and the display of competence. Evidence from cognitive science suggests that dreamers can also lose competence through forgetting and other cognitive incapacities but, more surprisingly, it is possible to gain abilities in a robust sense, consistent with the idea that some dreams, at least, are virtual realities rather than imagination.

Grounding, Conceivability, and the Mind-Body Problem

Khudairi, Hasen (2016) Grounding, Conceivability, and the Mind-Body Problem. Synthese. pp. 1-8. ISSN 0039-7857

Beyond Causal Explanation: Einstein’s Principle Not Reichenbach’s

Silberstein, Michael and Stuckey, W. M. (2021) Beyond Causal Explanation: Einstein’s Principle Not Reichenbach’s. In: UNSPECIFIED.

Models of the Nucleus: Incompatible Things, Compatible Processes

Penn, William (2021) Models of the Nucleus: Incompatible Things, Compatible Processes. [Preprint]

Probing Theoretical Statements with Thought Experiments

El Skaf, Rawad (2021) Probing Theoretical Statements with Thought Experiments. Synthese. ISSN 1573-0964