Big Bang Singularity Resolution In Quantum Cosmology |

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Fri Jan 27 2023 03:20:26 (1 day)

# 1.

Thebault, Karim P Y (2023) Big Bang Singularity Resolution In Quantum Cosmology. [Preprint]

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Thomas D. Galley, Flaminia Giacomini, John H. Selby

Thu Jan 26 2023 11:06:32 (1 day)

# 2.

When gravity is sourced by a quantum system, there is tension between its role as the mediator of a fundamental interaction, which is expected to acquire nonclassical features, and its role in determining the properties of spacetime, which is inherently classical. Fundamentally, this tension should result in breaking one of the fundamental principles of quantum theory or general relativity, but it is usually hard to assess which one without resorting to a specific model. Here, we answer this question in a theory-independent way using General Probabilistic Theories (GPTs). We consider the interactions of the gravitational field with a single matter system, and derive a no-go theorem showing that when gravity is classical at least one of the following assumptions needs to be violated: (i) Matter degrees of freedom are described by fully non-classical degrees of freedom; (ii) Interactions between matter degrees of freedom and the gravitational field are reversible; (iii) Matter degrees of freedom back-react on the gravitational field. We argue that this implies that theories of classical gravity and quantum matter must be fundamentally irreversible, as is the case in the recent model of Oppenheim et al. Conversely if we require that the interaction between quantum matter and the gravitational field are reversible, then the gravitational field must be non-classical.

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Pooya Farokhi, Tim Koslowski, Pedro Naranjo, Antonio Vassallo

Thu Jan 26 2023 11:06:24 (1 day)

# 3.

We provide the construction of a de Broglie-Bohm model of the $N$-body system within the framework of Pure Shape Dynamics. The equation of state of the curve in shape space is worked out, with the instantaneous shape being guided by a wave function. In order to get a better understanding of the dynamical system, we also give some numerical analysis for the 3-body case. Remarkably enough, our simulations typically show the attractor-driven behaviour of complexity, well known in the classical case, thereby providing further evidence for the claim that the arrow of complexity is the ultimate cause of the experienced arrow of time.

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Dominik Šafránek, Dario Rosa

Thu Jan 26 2023 11:06:17 (1 day)

# 4.

We present a method to estimate the mean value of any observable and its higher moments by measuring any other observable. This method is general and can be applied to any quantum system. In the case of estimating the mean energy of an isolated system, the estimate can be further improved by measuring the other observable at different times. Intuitively, this method uses interplay and correlations between the measured and the estimated observable, and the state of the system. We provide two bounds: one that is looser but analytically computable, and one that is tighter but requires solving a non-convex optimization problem. The method can be used to estimate expectation values and related quantities such as temperature and work in setups in which performing measurements in a highly entangled basis is difficult, finding use in state-of-the-art quantum simulators. As a demonstration, we show that in Heisenberg and Ising models of ten sites in the localized phase, performing two-qubit measurements excludes 97.5\% and 96.7\% of the possible range of energies, respectively, when estimating the ground state energy.

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Chao Xiao; Fei He; Quanqi Shi; Wenlong Liu; Anmin Tian; Ruilong Guo; Chao Yue; Xuzhi Zhou; Yong Wei; I. Jonathan Rae; Alexander W. Degeling; Vassilis Angelopoulos; Emmanuel V. Masongsong; Ji Liu; Qiugang Zong; Suiyan Fu; Zuyin Pu; Xiaoxin Zhang; Tieyan Wang; Huizi Wang; Zhao Zhang

Thu Jan 26 2023 08:00:00 (2 days)

# 5.

Nature Physics, Published online: 26 January 2023; doi:10.1038/s41567-022-01882-8

Lunar tides affect Earth’s oceans and its geomagnetic field. Multisatellite observations demonstrate that they also impact the plasmasphere.

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Tue Jan 24 2023 03:26:11 (4 days)

# 6.

Broka, Chris A. (2023) Quantum Measurements and their Place in Nature. [Preprint]

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Ludovico Lami; Bartosz Regula

Mon Jan 23 2023 08:00:00 (5 days)

# 7.

Nature Physics, Published online: 23 January 2023; doi:10.1038/s41567-022-01873-9

A formal analysis of the physical limits of entanglement manipulation shows that it cannot be done reversibly, highlighting an important difference from thermodynamics.

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M. O. Brown; S. R. Muleady; W. J. Dworschack; R. J. Lewis-Swan; A. M. Rey; O. Romero-Isart; C. A. Regal

Mon Jan 23 2023 08:00:00 (5 days)

# 8.

Nature Physics, Published online: 23 January 2023; doi:10.1038/s41567-022-01890-8

A tomography protocol that exploits the control offered by optical tweezers allows the reconstruction of motional states of a single trapped atom. This has implications for the study of non-classical states of massive trapped and levitated particles.

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Sun Jan 22 2023 13:35:37 (5 days)

# 9.

North, Jill and Baker, David John and Myrvold, Wayne C. and Ruetsche, Laura (2022) Author Meets Critics: Jill North, Physics, Structure and Reality. UNSPECIFIED.

]]>On gravitational effects of light. (arXiv:2301.08132v1 [physics.hist-ph]) |

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Alessio Rocci

Fri Jan 20 2023 10:09:23 (23 hours)

# 1.

Translation and Commentary of L\’eon Rosenfeld’s \”Uber die Gravitationwirkungen des Lichtes, Zeitschrift f\”ur Physik 65: 589-599 (1930). Originally published in German. Submitted for publication on September 26, 1930. (See [1] in the Comments with References section before reading this English translation). The gravitational field generated by an electromagnetic field is calculated using of laws of quantum mechanics and it is shown that the gravitational energy created turns out to be infinitely large, highlighting a new difficulty for the Heisenberg-Pauli quantum theory of wave fields. In addition, the transition processes, in which light and gravitational quanta are involved, that can take place in first approximation are briefly discussed.

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Alvaro Mozota Frauca

Fri Jan 20 2023 10:09:21 (23 hours)

# 2.

In this paper I raise a worry about the most extended resolutions of the problem of time of canonical quantizations of general relativity. The reason for this is that these resolutions are based on analogies with deparametrizable models for which the problem can be solved, while I argue in this paper that there are good reasons for doubting about these resolutions when the theory is not deparametrizable, which is the case of general relativity. I introduce an example of a non-deparametrizable model, a double harmonic oscillator system expressed by its Jacobi action, and argue that the problem of time for this model is not solvable, in the sense that its canonical quantization doesn’t lead to the quantum theory of two harmonic oscillators and the standard resolutions of the problem of time don’t work for this case. I argue that as general relativity is strongly analogous to this model, one should take seriously the view that the canonical quantization of general relativity doesn’t lead to a meaningful quantum theory. Finally, I comment that this has an impact on the foundations of different approaches to quantum gravity.

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J. M. Carmona, J. L. Cortés, J. J. Relancio, M. A. Reyes

Fri Jan 20 2023 10:09:16 (23 hours)

# 3.

Doubly special relativity considers a deformation of the special relativistic kinematics parametrized by a high-energy scale, in such a way that it preserves a relativity principle. When this deformation is assumed to be applied to any interaction between particles one faces some inconsistencies. In order to avoid them, we propose a new perspective where the deformation affects only the interactions between elementary particles. A consequence of this proposal is that the deformation cannot modify the special relativistic energy-momentum relation of a particle.

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Ryszard Horodecki

Fri Jan 20 2023 10:09:14 (23 hours)

# 4.

Dragan and Ekert in the paper New. J. Phys. \textbf{22} 033038 (2021) presented “quantum principle of relativity” (QPR) based on Galileo’s principle of relativity, which involves both superluminal $G_S$ and subluminal $G_s$ families of observers and argue that then they are considered on the same footing it “implies the emergence of non-deterministic dynamics, together with complex probability amplitudes and multiple trajectories.”. Here I discuss QPR in the context of Heisenberg’s classification of the fundamental physical theoretical models under the role universal constants of nature: Planck’s constant $\hslash$ and speed of light $c$. In particular I point out that the above conclusion is overestimated as both the superluminal and subluminal branches are separable in the sense that there is no mathematical coherent formalism that connect both branches of $G_S$ and $G_s$ together.

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Fri Jan 20 2023 07:21:04 (1 day)

# 5.

Sartori, Lorenzo (2022) Putting the ‘Experiment’ back into the ‘Thought Experiment’. Synthese, 201 (34). ISSN 1573-0964

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Satya Gontcho A Gontcho, Jean-Baptiste Kikwaya Eluo, Paul Gabor

Thu Jan 19 2023 09:48:43 (2 days)

# 6.

On December 31 2022, the Vlaamse Radio- en Televisieomroeporganisatie (VRT), the national public-service broadcaster for the Flemish Community of Belgium, recovered a video recording of a 1964 interview of Georges Lema\^itre. Up until now, that footage was thought to have been lost. This footage represents a unique insight into the views of the physicist often coined as the “father of the Big Bang”. The interview was conducted in French and is available online with Flemish subtitles. In an effort to make this treasure broadly available, we provide in this paper some brief context, an English translation of the interview as well as the French transcript for reference.

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J.E. Horvath, R. Rosas Fernandes, T.E. Idiart (Departamento de Astronomia, IAG-USP, São Paulo SP, Brazil)

Thu Jan 19 2023 09:48:42 (2 days)

# 7.

We discuss in this work the contradictory position in modern Physics between the existence of a microphysical quantum Reality and macrophysical classical one. After discussing some basic concepts in Philosophy, we revisit the situation of Quantum Mechanics results, particularly after the confirmation of violations of Bell’s Theorem, and its significance to create a tension between the micro and the macro world, which is very fundamental and unsolved.

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Hervé Zwirn

Thu Jan 19 2023 09:48:41 (2 days)

# 8.

I show how the quantum paradoxes occurring when we adopt a standard realist framework (or a framework in which the collapse implies a physical change of the state of the system) vanish if we abandon the idea that a measurement is related (directly or indirectly) to a physical change of state. In Convivial Solipsism, similarly to Everett interpretation, there is no collapse of the wave function. But contrary to Everett interpretation, there is only one world. This allows also to get rid of any non-locality and to provide a solution to the Wigner friend problem and its more recent versions.

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Julian Barbour

Thu Jan 19 2023 09:48:40 (2 days)

# 9.

I argue that the essence of gravity can be understood only in the context of the universe and that unrecognised implicit retention of Newtonian absolute scale and the impact of thermodynamics have obscured it. Typical attempts to resolve the conflict between maximal matter entropy in the early universe and the second law of thermodynamics illustrate my case. Rovelli, for example, argues that the scale factor, and with it the overall state, was out of equilibrium. He illustrates subsequent entropy-increasing interaction with other degrees of freedom in two models: particles in a box interacting with a piston initially out of equilibrium and Newtonian gravitating particles. However, the piston’s position and momentum, like the particles”, are defined relative to the box, while unobservable absolute space defines those of the gravitating particles. Their representation using observable scale-invariant variables shows that the box and gravitational statistics differ greatly: in the latter a single degree of freedom, gravity’s creative core, drives the system in every solution from entropic-like disorder to ever increasing ordered structure. Since in many ways such particles are a good approximation to general relativity, this may also be true for our universe.

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Layton A. Hall; Ayman F. Abouraddy

Thu Jan 19 2023 08:00:00 (2 days)

# 10.

Nature Physics, Published online: 19 January 2023; doi:10.1038/s41567-022-01876-6

de Broglie–Mackinnon wave packets are an extension of matter waves, but have so far remained a theoretical construct. Combining spatio-temporal light fields with anomalous dispersion has now allowed their experimental observation.

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Mbaye Diouf; Joshua A. Burrow; Kimani C. Toussaint Jr.

Thu Jan 19 2023 08:00:00 (2 days)

# 11.

Nature Physics, Published online: 19 January 2023; doi:10.1038/s41567-022-01861-z

Long-theorized, non-dispersive de Broglie wave packets have been optically synthesized using classically entangled ring-shaped space-time wave packets in a medium exhibiting anomalous dispersion.

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Thu Jan 19 2023 07:00:23 (2 days)

# 12.

Mulder, Ruward A. and Muller, F.A. (2022) Modal-Logical Reconstructions of Thought Experiments. [Preprint]

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Thu Jan 19 2023 06:58:49 (2 days)

# 13.

Luk, Robert (2023) Principle Theory or Constructive Theory? UNSPECIFIED.

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Wed Jan 18 2023 11:42:28 (2 days)

# 14.

Petkov, Vesselin (2023) Relativistic Mass is an Experimental Fact. [Preprint]

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Tue Jan 17 2023 17:53:28 (3 days)

# 15.

Koberinski, Adam and Fraser, Doreen (2023) Renormalization group methods and the epistemology of effective field theories. [Preprint]

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Daniel Kaplan; Michael Kaplan

Tue Jan 17 2023 08:00:00 (4 days)

# 16.

Nature Physics, Published online: 17 January 2023; doi:10.1038/s41567-022-01901-8

An endless pursuit

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Tue Jan 17 2023 08:00:00 (4 days)

# 17.

Nature Physics, Published online: 17 January 2023; doi:10.1038/s41567-022-01936-x

As 2023 begins, we look forward to some of the new things the journal will do this year and introduce the team of editors who will do them.

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Tue Jan 17 2023 03:11:26 (4 days)

# 18.

Adlam, Emily (2022) Do We Have Any Viable Solution to the Measurement Problem? [Preprint]

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Urjit A. Yajnik

Mon Jan 16 2023 17:49:07 (4 days)

# 19.

The laws of quantum mechanics are couched in subtle mathematical language. The laws are not usually stated in a compact pedagogical form. Here I present a possible way to correct this. Essential facts can be distilled into seven statements that are easy to remember and easily referred back. Also, the current teaching of quantum mechanics is laden with words of negative connotations, originating as they did during the early decades of the subject when the subject was intellectually still puzzling. A wide variety of experiments in the intervening decades, not least those that were awarded the Nobel Prize of 2022 amply affirm the validity and substantial “reality” of Quantum Mechanics as a theory. I take a few of the inadequacies of classical framework to illustrate that some of the complaints against Quantum Mechanics are patently misplaced. Finally I discuss the bogeys such as “wave article duality”, “uncertainty”, “indistinguishability” “statistics” and “entanglement” and advocate adopting better terminology to save new learners from the old biases.

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Bartosz Jura

Mon Jan 16 2023 17:49:05 (4 days)

# 20.

In this work a model is proposed, according to which causality can be considered to be spatio-temporally graded. It is outlined how this can be described using the formalism of fuzzy sets theory, with the degree of causality varying between 1, that is no separation between causes and effects, and 0, that is perfect separation between causes and their effects as in classical ‘billiard balls’ models of physical systems. The model posits that subjective moments of time are like fuzzy sets, with their extension determined by local degrees of causality, resulting from information integration processes extended gradually in space and time. This, we argue, is a way in which a notion of causality could be, to a certain degree, spared and reconciled with a variant of Bergsonian duration theory as formulated in the theory of continuous change as the dimension of consciousness.

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Giovanni Lapenta

Mon Jan 16 2023 08:00:00 (5 days)

# 21.

Nature Physics, Published online: 16 January 2023; doi:10.1038/s41567-022-01864-w

Particles in space can be accelerated to high energy, the distribution of which follows a power law. This has now been reproduced in laboratory experiments mimicking astrophysical scenarios, which helps to understand the underlying mechanisms.

]]>Born rule: quantum probability as classical probability |

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Sat Jan 14 2023 03:03:27 (6 hours)

# 1.

Stoica, Ovidiu Cristinel (2022) Born rule: quantum probability as classical probability. [Preprint]

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Sat Jan 14 2023 03:02:06 (6 hours)

# 2.

Stoica, Ovidiu Cristinel (2022) Background freedom leads to many-worlds with local beables and probabilities. [Preprint]

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Sat Jan 14 2023 03:00:01 (6 hours)

# 3.

Price, Huw and Wharton, Ken (2022) Why entanglement? [Preprint]

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Michèle Levi

Wed Jan 11 2023 10:24:32 (2 days)

# 4.

We take a tour through the past, present and future of Effective Field Theory, with applications ranging from LHC physics to cosmology.

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Maxime Federico, Philippe Grangier

Tue Jan 10 2023 10:12:38 (3 days)

# 5.

We present a discussion of the extended Wigner’s friend thought experiment proposed by Frauchiger and Renner in [1]. We show by using various arguments, including textbook quantum mechanics and the ontological approach of Contexts, Systems, Modalities (CSM), that no contradiction arises if one admits that agents must agree on what is considered as a system and what is not. In such a contextually objective approach of quantum mechanics, the apparent contradiction is automatically removed. We also discuss why this mutual agreement between agents is already implicit in the standard formulations of quantum mechanics, and why removing it leads to inconsistencies.

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Michael E. Cuffaro

Tue Jan 10 2023 10:12:35 (3 days)

# 6.

I argue that Immanuel Kant’s critical philosophy — in particular the doctrine of transcendental idealism which grounds it — is best understood as an `epistemic’ or `metaphilosophical’ doctrine. As such it aims to show how one may engage in the natural sciences and in metaphysics under the restriction that certain conditions are imposed on our cognition of objects. Underlying Kant’s doctrine, however, is an ontological posit, of a sort, regarding the fundamental nature of our cognition. This posit, sometimes called the `discursivity thesis’, while considered to be completely obvious and uncontroversial by some, has nevertheless been denied by thinkers both before and after Kant. One such thinker is Jakob Friedrich Fries, an early neo-Kantian who, despite his rejection of discursivity, also advocated for a metaphilosophical understanding of critical philosophy. As I will explain, a consequence for Fries of the denial of discursivity is a radical reconceptualisation of the method of critical philosophy; whereas this method is a priori for Kant, for Fries it is in general empirical. I discuss these issues in the context of quantum theory, and I focus in particular on the views of the physicist Niels Bohr and the Neo-Friesian philosopher Grete Hermann. I argue that Bohr’s understanding of quantum mechanics can be seen as a natural extension of an orthodox Kantian viewpoint in the face of the challenges posed by quantum theory, and I compare this with the extension of Friesian philosophy that is represented by Hermann’s view.

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Costantino Budroni, Adán Cabello, Otfried Gühne, Matthias Kleinmann, Jan-Åke Larsson

Tue Jan 10 2023 10:12:34 (3 days)

# 7.

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 implemented simultaneously or, more generally, those that are jointly measurable. This conflict is generically called quantum contextuality. In this review, an introduction to this subject and its current status is presented. Several proofs of the Kochen-Specker theorem and different notions of contextuality are reviewed. How to experimentally test some of these notions is explained and connections between contextuality and nonlocality or graph theory are discussed. Finally, some applications of contextuality in quantum information processing are reviewed.

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Adam R. Brown

Mon Jan 09 2023 08:00:00 (5 days)

# 8.

Nature Physics, Published online: 09 January 2023; doi:10.1038/s41567-022-01884-6

Quantum operations can be considered as points in a high-dimensional space in which distance reflects the similarity of two operations. Applying differential-geometric methods in this picture gives insights into the complexity of quantum systems.

]]>The comprehensive analysis of Niels Bohr shows that the classical world is a necessary additional independent conceptual structure not derivable from quantum mechanics. The results of measurement must always be expressed classically. Furthermore, neither linear “decoherence”, nor any other unitary linear models/interpretations can ever result in the observed *nonlinear *classical physics. As we will see, the invariant objective classical events constituting the dynamically nonlinear spacetime of general relativity *is *this classical structure. Hence, *classical *gravitation is required to make the abstract and purely formal, perfectly linear, quantum mechanical eternal coexistence of many mutually incompatible possibilities into the concrete reality of the observed nonlinear world. It also means that “Quantum Gravity” is a pseudo-problem, a mirage, “Quantum Spacetime” an oxymoron.

A Simple Derivation of the Gertsenshtein Effect. (arXiv:2301.02072v1 [gr-qc]) |

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Andrea Palessandro, Tony Rothman

Fri Jan 06 2023 09:57:34 (1 day)

# 1.

As shown by Gertsenshtein in 1961, an external magnetic field can catalyze the mixing of graviton and photon states in a manner analogous to neutrino-flavor oscillations. We first present a straightforward derivation of the mechanism by a method based on unpublished notes of Freeman Dyson. We next extend his method to include boundary conditions and retrieve the results of Boccaletti et al. from 1970. We point out that, although the coupling between the graviton and photons states is extremely weak, the large magnetic fields around neutron stars $\sim 10^{14}$ G make the Gertsenshtein effect a plausible source of gravitons. Indeed, an “in principle” observable consequence would be the change of optical brightness of a neutron star between directions parallel and perpendicular to the field. We also point out that axion-photon mixing, a subject of active current research, is essentially the same process as the Gertsenshtein effect, and so the general mechanism may be of broad astrophysical and cosmological interest.

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Alexey A. Kryukov

Fri Jan 06 2023 09:57:32 (1 day)

# 2.

The motion of a ball through an appropriate lattice of round obstacles models the behavior of a Brownian particle and can be used to describe measurement on a macro system. On another hand, such motion is chaotic and a known conjecture asserts that the Hamiltonian of the corresponding quantum system must follow the random matrix statistics of an appropriate ensemble. We use the Hamiltonian represented by a random matrix in the Gaussian unitary ensemble to study the Schrodinger evolution of non-stationary states. For Gaussian states representing a classical system, the Brownian motion that describes the behavior of the system under measurement is obtained. For general quantum states, the Born rule for the probability of transition between states is derived. It is then shown that the Schrodinger evolution with such a Hamiltonian models measurement on macroscopic and microscopic systems, provides an explanation for the classical behavior of macroscopic bodies and for irreversibility of a measurement, and identifies the boundary between micro and macro worlds.

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Sinya Aoki

Fri Jan 06 2023 09:57:29 (1 day)

# 3.

Noether’s 2nd theorem applied to a total system states that a global symmetry which is a part of local symmetries does not provide a physically meaningful conserved charge but it instead leads to off-shell constraints as a form of conserved currents. In this paper, we propose a general method to derive a matter conserved current associated with a special global symmetry in the presence of local symmetries. While currents derived from local symmetries of a matter sector with a covariant background gauge field are not conserved in general, we show that the current associated with a special type of a global symmetry, called a hidden matter symmetry, is on-shell conserved. We apply this derivation to a $U(1)$ gauge theory, general relativity and a non-abelian gauge theory. In general relativity, the associated conserved charge agrees with the one recently proposed from a different point of view.

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Simone Gasparinetti

Thu Jan 05 2023 08:00:00 (2 days)

# 4.

Nature Physics, Published online: 05 January 2023; doi:10.1038/s41567-022-01896-2

The emission of light from qubits in a superconducting circuit can be controlled in order to choose the direction of the photons’ propagation, which could be used to route information in quantum networks.

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John Klasios

Wed Jan 04 2023 10:08:30 (2 days)

# 5.

The cognitive scientist Donald Hoffman argues that we don’t perceive reality: spacetime, objects, colors, sounds, tastes, and so forth, are all merely an interface that we evolved to track evolutionary fitness rather than to perceive truths about external reality. In this paper, I expound on his argument, then I extend it, primarily, by looking at key ideas in physics that are quite germane to it. Among the topics in physics that I discuss are black holes, the holographic principle, string theory, duality, quantum gravity, and special relativity. I discuss these ideas from physics with an eye to their relevance for Hoffman’s view.

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Wed Jan 04 2023 03:30:21 (3 days)

# 6.

Kastner, Ruth (2022) Quantum Systems and Identity: Against “Permutation Invariance”. [Preprint]

]]>By subjecting the de Broglie wave to an inverse Lorentz transformation, an attempt is made to return this mysterious wave to a form that is physically viable in the rest frame of the associated particle. The attempt is unsuccessful: it is found that in that frame, the wave becomes an oscillation that varies in time, but not in space, and cannot be identified with the spatially-extended sinusoidal wave that accompanies the moving particle. It is shown that this difficulty is a consequence of the restricted manner in which de Broglie reconciled the phases of particle and wave in his doctoral thesis of 1924. Although he assumed that the particle is surrounded in its rest frame by a spatially extended “periodic phenomenon”, he applied his “theorem of the harmony of phases”, not to that extended waveform, but to a single oscillating point within the waveform. As such a point moves, it does describe a sinusoidally varying phase, but this is the varying phase, not of a wave, but of a moving and oscillating point. Had de Broglie applied his harmonizing of phase to the full underlying waveform, a wave with the characteristics of the de Broglie wave would have emerged, in a physically reasonable manner, as the relativistically induced modulation (a dephasing) of the underlying wave structure. After showing that there is considerable support for this interpretation in de Broglie’s thesis, consideration is given to the implications of such an interpretation for relativity, quantum mechanics and particle structure.

]]>The process approach to NRQM offers a fourth framework for the quantization of physical systems. Unlike the standard approaches (Schrodinger-Heisenberg, Feynman, Wigner-Gronewald-Moyal), the process approach is *not* equivalent to NRQM and is *not* merely a re-interpretation. The process approach provides a dynamical *completion* of NRQM. Standard NRQM arises as a asymptotic quotient by means of a set-valued process covering map, which links the process algebra to the usual space of wave functions and operators on Hilbert space. The process approach offers an emergentist, discrete, finite, quasi-non-local and quasi-non-contextual realist interpretation which appears to resolve many of the paradoxes and is free of divergences. Nevertheless, it retains the computational power of NRQM and possesses an emergent probability structure which agrees with NRQM in the asymptotic quotient. The paper describes the process algebra, the process covering map for single systems and the configuration process covering map for multiple systems. It demonstrates the link to NRQM through a toy model. Applications of the process algebra to various quantum mechanical situations – superpositions, two-slit experiments, entanglement, Schrodinger’s cat – are presented along with an approach to the paradoxes and the issue of classicality.

Sleeping Beauty Remains Undecided |

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Fri Dec 30 2022 21:22:11 (12 hours)

# 1.

Burock, Marc (2022) Sleeping Beauty Remains Undecided. [Preprint]

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Fri Dec 30 2022 21:20:37 (12 hours)

# 2.

Koberinski, Adam (2022) What good is Haag’s no-go theorem? What axiomatic methods can teach us about particle physics. In: UNSPECIFIED.

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Fri Dec 30 2022 21:16:29 (12 hours)

# 3.

Oriti, Daniele (2022) Tightrope-walking rationality in action: Feyerabendian insights for the foundations of quantum mechanics. [Preprint]

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T. Rick Perche, Eduardo Martín-Martínez

Thu Dec 29 2022 12:16:05 (1 day)

# 4.

We analyze the differences between relativistic fields with or without quantum degrees of freedom in relativistic quantum information protocols. We classify the regimes where the existence of quantum degrees of freedom is necessary to explain the phenomenology of interacting quantum systems. We also identify the precise regimes where quantum fields can be well approximated by quantum-controlled classical fields in relativistic quantum information protocols. Our results can be useful to discern which features are fundamentally different in classical and quantum field theory.

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Samuel Leutheusser, Hong Liu

Thu Dec 29 2022 12:16:04 (1 day)

# 5.

In holographic duality, a higher dimensional quantum gravity system emerges from a lower dimensional conformal field theory (CFT) with a large number of degrees of freedom. We propose a formulation of duality for a general causally complete bulk spacetime region, called subalgebra-subregion duality, which provides a framework to describe how geometric notions in the gravity system, such as spacetime subregions, different notions of times, and causal structure, emerge from the dual CFT. Subalgebra-subregion duality generalizes and brings new insights into subregion-subregion duality (or equivalently entanglement wedge reconstruction). It provides a mathematically precise definition of subregion-subregion duality and gives an independent definition of entanglement wedges without using entropy. Geometric properties of entanglement wedges, including those that play a crucial role in interpreting the bulk as a quantum error correcting code, can be understood from the duality as the geometrization of the additivity anomaly of certain algebras. Using general boundary subalgebras rather than those associated with geometric subregions makes it possible to find duals for general bulk spacetime regions, including those not touching the boundary. Applying subalgebra-subregion duality to a boundary state describing a single-sided black hole also provides a precise way to define mirror operators.

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Jakub M. Ratajczak

Thu Dec 29 2022 12:16:02 (1 day)

# 6.

Quantum mechanics has lacked a widely recognized interpretation since its birth. Many of these are still under consideration because interpretations are tough or impossible to disprove experimentally. We show how to distinguish experimentally ones assuming tiny, localized particles from those postulating realistic, non-local wave functions. It is possible thanks to a recently developed model of optical transmittance of ultra-diluted gas. This model considers the influence of each gas particle wave function on transmitted light. Its quantitative predictions are not indifferent to the interpretation of quantum mechanics. We also refer to the results of a recent experiment founded on this theory. They are in line with the predictions, which suggests the correctness of the model. Such results, if confirmed, rule out interpretations of the type of pilot-wave. In the paper, we briefly explain both the experiment and the model it is founded on. We also discuss the meaning of the Born rule.

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Ngo Phuc Duc Loc

Thu Dec 29 2022 12:16:00 (1 day)

# 7.

We know that space and time are treated almost equally in classical physics, but we also know that this is not the case for quantum mechanics. A quantum description of both space and time is important to really understand the quantum nature of reality. The Page-Wootters mechanism of quantum time is a promising starting point, according to which the evolution of the quantum system is described by the entanglement between it and quantum temporal degrees of freedom. In this paper, we use a qubit clock model to study how the time-system entanglement measures depend on the rapidity when the quantum system is Lorentz boosted. We consider the case of a spin-1/2 particle with Gaussian momentum distribution as a concrete example.

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Shurui Wu, Bing-Qian Wang, Z. W. Long, Hao Chen

Thu Dec 29 2022 12:15:53 (1 day)

# 8.

Recently, Elias C. Vagenas et al and Yongwan Gim et al studied the validity of the no-cloning theorem in the context of generalized uncertainty principle (GUP), but they came to conflicting conclusions. Motivated by a recent work presented by Xin-Dong Du, we investigate the corrections to the temperature for Schwarzschild black hole in the context of different forms of GUP, and obtain the required energy to duplicate information for the Schwarzschild black hole, it shows that the no-cloning theorem in the present of GUP is safe.

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J. Fernando Barbero G., Daniele Pranzetti

Thu Dec 29 2022 12:15:52 (1 day)

# 9.

We give an account of the state of the art about black hole entropy in Loop Quantum Gravity. This chapter contains a historical summary and explains how black hole entropy is described by relying on the concept of isolated horizon, with an emphasis on different representations of its associated symmetry group. It continues with a review of the combinatorial methods necessary to understand the behavior of the entropy as a function of the area and concludes with a discussion of the nature of the quantum horizon degrees of freedom that account for the black hole entropy and the related issue of the fixing of the Immirzi parameter.

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Wed Dec 28 2022 07:30:45 (3 days)

# 10.

Price, Huw and Wharton, Ken (2022) Why entanglement? [Preprint]

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Wed Dec 28 2022 07:29:35 (3 days)

# 11.

Sagrafena, Cristina (2022) The Old Evidence Problem and the Inference to the Best Explanation. [Preprint]

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The Prediction of Anyons: Its History and Wider Implications. (arXiv:2212.12632v1 [physics.hist-ph]) |

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Gerald A. Goldin

Tue Dec 27 2022 10:26:50 (3 days)

# 12.

Prediction of “anyons”, often attributed exclusively to Wilczek, came first from Leinaas & Myrheim in 1977, and independently from Goldin, Menikoff, & Sharp in 1980-81. In 2020, experimentalists successfully created anyonic excitations. This paper discusses why the possibility of quantum particles in two-dimensional space with intermediate exchange statistics eluded physicists for so long after bosons and fermions were understood. The history suggests ideas for the preparation of future researchers. I conclude by addressing failures to attribute scientific achievements accurately. Such practices disproportionately hurt women and minorities in physics, and are harmful to science.

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Dora Musielak

Tue Dec 27 2022 10:26:49 (3 days)

# 13.

Euler stressed the importance of hypotheses, which he thought were the only means of arriving at a certain knowledge of the physical causes, essential to establish the laws of physics. This thought was communicated to \’Emilie du Ch\^atelet in response to hers when she debated the nature of forces, defending vis viva. In this paper, I examine the topics Euler discussed and place them in a context with the scientific and philosophical research of the seventeenth and eighteenth centuries that sought to establish the principles of nature. The source of this analysis centers on a fragment of an undated letter addressed to Ch\^atelet discovered in the archives of the Leningrad Archive of the Soviet Academy of Sciences, a piece which has received little attention. Albeit incomplete, the Euler-Ch\^atelet correspondence is historically and culturally important because the ideas addressed are part of the knowledge base of the development of physics, mathematics, and natural philosophy.

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Aurélien Drezet

Tue Dec 27 2022 10:26:47 (3 days)

# 14.

In order to celebrate this double birthday the journal Foundations of Physics publishes a topical collection `Pilot-wave and beyond’ on the developments that have followed the pioneering works of Louis de Broglie and David Bohm on quantum foundations. This topical collection includes contributions from physicists and philosophers debating around the world about the scientific legacy of Bohm and de Broglie concerning the interpretation and understanding of quantum mechanics. In these forewords we give a general review of the historical context explaining how de Broglie and Bohm developed their interpretations of quantum mechanics. We further analyze the relationship between these two great thinkers and emphasize the role of several collaborators and continuators of their ontological approach to physics.

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Feraz Azhar, Alan H. Guth, Mohammad Hossein Namjoo

Tue Dec 27 2022 10:26:46 (3 days)

# 15.

In “Defeating Dr. Evil with Self-Locating Belief”, Adam Elga proposes and defends a principle of indifference for self-locating beliefs: if an individual is confident that his world contains more than one individual who is in a state subjectively indistinguishable from his own, then he should assign equal credences to the hypotheses that he is any one of these individuals. Through a sequence of thought experiments, Elga in effect claims that he can derive the credence function that should apply in such situations, thus justifying his principle of indifference. Here we argue, using a Bayesian approach, that Elga’s reasoning is circular: in analyzing the third of his thought experiments, he uses an assertion that is justifiable only if one assumes, from the start, the principle of indifference that he is attempting to justify. We agree with Elga that the assumption of equal credences is a very reasonable principle, in the absence of any reason to assign unequal credences, but we do not agree that the equality of credences can be so derived.

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Antony Valentini

Mon Dec 26 2022 10:10:48 (4 days)

# 16.

We have recently developed a new understanding of probability in quantum gravity. In this paper we provide an overview of this new approach and its implications. Adopting the de Broglie-Bohm pilot-wave formulation of quantum physics, we argue that there is no Born rule at the fundamental level of quantum gravity with a non-normalisable Wheeler-DeWitt wave functional $\Psi$. Instead the universe is in a perpetual state of quantum nonequilibrium with a probability density $P\neq\left\vert \Psi\right\vert ^{2}$. Dynamical relaxation to the Born rule can occur only after the early universe has emerged into a semiclassical or Schr\”{o}dinger approximation, with a time-dependent and normalisable wave functional $\psi$, for non-gravitational systems on a classical spacetime background. In that regime the probability density $\rho$ can relax towards $\left\vert \psi\right\vert ^{2}$ (on a coarse-grained level). Thus the pilot-wave theory of gravitation supports the hypothesis of primordial quantum nonequilibrium, with relaxation to the Born rule taking place soon after the big bang. We also show that quantum-gravitational corrections to the Schr\”{o}dinger approximation allow quantum nonequilibrium $\rho\neq\left\vert \psi\right\vert ^{2}$ to be created from a prior equilibrium ($\rho=\left\vert \psi\right\vert ^{2}$) state. Such effects are very tiny and difficult to observe in practice.

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Marcello Poletti

Mon Dec 26 2022 10:10:47 (4 days)

# 17.

Here we continue with the ideas expressed in “On the strangeness of quantum mechanics” aiming to demonstrate more concretely how this philosophical outlook might be used as a key for resolving the measurement problem. We will address in detail the problem of determining how the concept of undecidability leads to substantial changes to classical theory of probability by showing how such changes produce a theory that coincides with the principles underlying quantum mechanics.

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Emanuele Goldoni, Ledo Stefanini

Mon Dec 26 2022 10:10:46 (4 days)

# 18.

In April 1925, Enrico Fermi was only 23 years old and he had graduated less than three years earlier. Despite his age, Fermi was invited at the University of Rome by Federigo Enriques to give several lectures on the recent advances in physics at the Italian Mathematics Seminar. Enriques was also the editor of “Periodico di Matematiche”, an important Italian journal concerned primarily with secondary school math teachers. Some of the articles published by “Periodico di Matematiche” correspond to the lectures which Fermi gave during seminars and meetings of Italian mathematicians. Here we propose an English translation for one of these articles, entitled “Sopra la teoria cinetica dei corpi solidi” and discussing the kinetic theory of solids. We believe that this Fermi’s work offers a twofold interesting perspective: on one side, it allows us to explore the problems related to the structure of matter of emerging at the time as seen by the eyes of a bright, young physicist. On the other hand, it shows us the undoubtedly high scientific level of the articles read in Italy by the secondary school math teachers in the Twenties.

]]>Review on Non-Relativistic Gravity. (arXiv:2212.11309v1 [gr-qc]) |

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Jelle Hartong, Niels A. Obers, Gerben Oling

Fri Dec 23 2022 11:08:27 (22 hours)

# 1.

We review the history of Newton-Cartan gravity with an emphasis on recent developments, including the covariant, off-shell large speed of light expansion of general relativity. Depending on the matter content, this expansion either leads to Newton-Cartan geometry with absolute time or to Newton-Cartan geometry with non-relativistic gravitational time dilation effects. The latter shows that non-relativistic gravity includes a strong field regime and goes beyond Newtonian gravity. We start by reviewing early developments in Newton-Cartan geometry, including the covariant description of Newtonian gravity, mainly through the works of Trautman, Dautcourt, K\”unzle and Ehlers. We then turn to more modern developments, such as the gauging of the Bargmann algebra, and we describe why the latter cannot be used to find an off-shell covariant description of Newtonian gravity. We review recent work on the $1/c$ expansion of general relativity and show that this leads to an alternative `type II’ notion of Newton-Cartan geometry. Finally, we discuss matter couplings, solutions and odd powers in $1/c$, and we conclude with a brief summary of related topics.

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Fri Dec 23 2022 06:50:58 (1 day)

# 2.

Dewar, Neil (2022) Equivalence and Convention. In: UNSPECIFIED.

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

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Anne-Catherine de la Hamette, Stefan L. Ludescher, and Markus P. Müller

Thu Dec 22 2022 18:00:00 (1 day)

# 3.

Author(s): Anne-Catherine de la Hamette, Stefan L. Ludescher, and Markus P. Müller

In the quantization of gauge theories and quantum gravity, it is crucial to treat reference frames such as rods or clocks not as idealized external classical relata, but as internal quantum subsystems. In the Page-Wootters formalism, for example, evolution of a quantum system S is described by a sta…

[Phys. Rev. Lett. 129, 260404] Published Thu Dec 22, 2022

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Renxin Xu (PKU)

Thu Dec 22 2022 11:59:09 (1 day)

# 4.

In the late age of developing quantum mechanics, Lev Landau, one of the distinguished players, made great efforts to understand the nature of matter, even stellar matter, by applying the quantum theory. Ninety years ago, he published his idea of “neutron” star, which burst upon him during his visit over Europe in the previous year. The key point that motivated Landau to write the paper is to make a state with lower energy for “gigantic nucleus”, avoiding extremely high kinematic energy of electron gas due to the new Fermi-Dirac statistics focused hotly on at that time. Landau had no alternative but to neutronize/neutralize by “combining a proton and an electron”, as electron and proton were supposed to be elementary before the discovery of neutron. However, our understanding of the Nature has fundamentally improved today, and another way (i.e., strangeonization) could also embody neutralization and thus a low-energy state that Landau had in mind, which could further make unprecedented opportunities in this multi-messenger era of astronomy. Strangeon matter in “old” physics may impact dramatically on today’s physics, from compact stars initiated by Landau, to cosmic rays and dark matter. In this essay, we are making briefly the origin and development of neutron star concept to reform radically, to remember Landau’s substantial contribution in astrophysics and to recall those peculiar memories.

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Rüdiger Schack

Thu Dec 22 2022 11:59:08 (1 day)

# 5.

Following earlier work by Michel Bitbol (Bitbol 2020) and Laura de la Tremblaye (de La Tremblaye 2020) which examines QBism from the perspective of phenomenology, this short paper explores points of contact between QBism and Maurice Merleau-Ponty’s essay The intertwining — the chiasm.

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Marko Toroš, Marion Cromb, Mauro Paternostro, and Daniele Faccio

Wed Dec 21 2022 18:00:00 (2 days)

# 6.

Author(s): Marko Toroš, Marion Cromb, Mauro Paternostro, and Daniele Faccio

Many phenomena and fundamental predictions, ranging from Hawking radiation to the early evolution of the Universe rely on the interplay between quantum mechanics and gravity or more generally, quantum mechanics in curved spacetimes. However, our understanding is hindered by the lack of experiments t…

[Phys. Rev. Lett. 129, 260401] Published Wed Dec 21, 2022

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Wed Dec 21 2022 03:05:45 (3 days)

# 7.

Boge, Florian J. (2022) Back to Kant! QBism, Phenomenology, and Reality from Invariants. [Preprint]

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Reidun Renstrøm, Nils-Erik Bomark

Tue Dec 20 2022 09:13:21 (4 days)

# 8.

Most physics textbooks at college and university level introduce quantum physics in a historical context. However, the textbook version of this history does not match the actual history. In this article, the first in a series of articles looking at the textbook description of the quantum history, we follow an exceptional student through her endeavors to understand the early atomic models that led up to the work of Niels Bohr. We experience her disappointment when she discovers that the description of the famous atomic model by Thomson, is a mere caricature with almost no trace of Thomson’s work and that the supposedly important radiative instability of Rutherford’s atoms, is not there at all; how could it be? Rutherford did not even discuss the motion of the electrons. These flaws in the narrative are not just cosmetic inaccuracies, the main narrative is centered around claims that are simply wrong or non-existent in the real story and thus rendering the whole telling mere fiction. We as a physics community should do better.

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Mon Dec 19 2022 12:03:13 (4 days)

# 9.

Danne, Nicholas (2022) Is Fourier Analysis Conservative over Physical Theory? [Preprint]

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Mon Dec 19 2022 12:01:13 (4 days)

# 10.

Baron, Sam and Le Bihan, Baptiste (2023) Causal Theories of Spacetime. [Preprint]

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Sun Dec 18 2022 02:24:51 (6 days)

# 11.

Price, Huw and Wharton, Ken (2022) Why entanglement? [Preprint]

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Sat Dec 17 2022 03:17:07 (1 week)

# 12.

Sartori, Lorenzo (2022) Putting the ‘Experiment’ Back into the ‘Thought Experiment’. [Preprint]

]]>Noise-Induced Quantum Synchronization |

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

by

Finn Schmolke and Eric Lutz

Fri Dec 16 2022 18:00:00 (1 day)

# 1.

Author(s): Finn Schmolke and Eric Lutz

Noise-induced synchronization can occur in the quantum regime as well as the classical, and by applying noise to a single spin in an arbitrarily long chain, one can synchronize the entire chain.

[Phys. Rev. Lett. 129, 250601] Published Fri Dec 16, 2022

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Fri Dec 16 2022 07:33:45 (2 days)

# 2.

Lorenzetti, Lorenzo (2022) Two Forms of Functional Reductionism in Physics. [Preprint]

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Fri Dec 16 2022 07:30:22 (2 days)

# 3.

Pruss, Alexander R. (2022) Strict Dominance and Symmetry. [Preprint]

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Jonah Kudler-Flam, Yuya Kusuki

Thu Dec 15 2022 11:09:31 (2 days)

# 4.

While recent progress in the black hole information problem has shown that the entropy of Hawking radiation follows a unitary Page curve, the quantum state of Hawking radiation prior the Page time is still treated as purely thermal, containing no information about the microstructure of the black hole. We demonstrate that there is significant quantum information regarding the quantum state of the black hole in the Hawking radiation prior to the Page time. By computing of the quantum fidelity in a 2D boundary conformal field theory (BCFT) model of black hole evaporation, we demonstrate that an observer outside of an evaporating black hole may distinguish different black holes via measurements of the Hawking radiation at \textit{any} time during the evaporation process, albeit with an exponentially large number of measurements. Furthermore, our results are universal, applicable to general BCFTs including those with large central charge and rational BCFTs. The techniques we develop for computing the fidelity are more generally applicable to excited states in CFT. As such, we are able to characterize more general aspects of thermalization in 2D conformal field theory.

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Huw Price, Ken Wharton

Thu Dec 15 2022 11:09:30 (2 days)

# 5.

We propose a mechanism for quantum entanglement. The key ingredient is the familiar statistical phenomenon of collider bias, or Berkson’s bias. In the language of causal models a collider is a variable causally influenced by two or more other variables. Conditioning on a collider typically produces non-causal associations between its contributing causes, even if they are actually independent. It is easy to show that this phenomenon can produce associations analogous to Bell correlations, in suitable post-selected ensembles. It is also straightforward that such collider artefacts may become real connections, resembling causality, if a collider is ‘constrained’ (e.g., by a future boundary condition). We consider the time-reversed analogues of these points in the context of retrocausal models of QM. Retrocausality yields a collider at the source of an EPR-Bell particle pair, and in this case constraint of the collider is possible by normal methods of experimental preparation. It follows that connections resembling causality may be expected to emerge across such colliders, from one branch of the experiment to the other. Our hypothesis is that this constrained retrocausal collider bias is the origin of entanglement. The piece is written for a general audience, and is based on a suggestion first made in arXiv:2101.05370 [quant-ph].

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Francisco Tello-Ortiz, B.Mishra, A. Alvarez, Ksh. Newton Singh

Thu Dec 15 2022 11:09:29 (2 days)

# 6.

In this article, new wormhole solutions in the framework of General Relativity are presented. Taking advantage of gravitational decoupling by means of minimal geometric deformation approach and, the so-called noncommutative geometry Gaussian and Lorentzian density profiles, the seminal Morris-Thorne space-time is minimally deformed providing new asymptotically wormhole solutions. Constraining the signature of some parameters, the dimensionless constant $\alpha$ is bounded using the flare-out and energy conditions. In both cases, this results in an energy-momentum tensor that violates energy conditions, thus the space-time is threading by exotic matter. However, it is possible to obtain a positive defined density at the wormhole throat and its neighborhood. To further support the study a thoroughly graphical analysis has been performed.

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Chris Stevens, Oliver Markwell

Thu Dec 15 2022 11:09:28 (2 days)

# 7.

Conformal Cyclic Cosmology (CCC) is a cyclic model of the universe put forward by Sir Roger Penrose. A conformal invariance assumption in the neighbourhood of the crossover region between cycles (which Penrose calls aeons) allows successive space-times to be related by a conformal rescaling. A major open problem is how to choose the conformal factor in a unique way, and is a fundamental hurdle to further study. Proposals have been put forward by Newman, Tod and Nurowski, but they disagree in one way or another with Penrose’s original assumptions as well as each other. In this paper we compare these different models in detail and rule out certain choices for the conformal factor that have been put forward by Penrose. We extend the results of Newman and fix inconsistencies that arose in his calculations. A new class of solutions are put forward which agree with Penrose’s assumptions exactly so long as a certain additional relation is satisfied. We also correct a CCC solution presented by Nurowski.

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P. J. Bussey

Thu Dec 15 2022 11:09:27 (2 days)

# 8.

A detailed consideration of the Klein-Gordon equation in relativistic quantum mechanics is presented in order to offer more clarity than many standard approaches. The equation is frequently employed in the research literature, even though problems have often been raised regarding its second-order nature, the status of its negative-energy solutions and the formulation of particle density and flux. Most of these problems can be avoided by dismissing the negative-energy solutions. An application of the equation to a broad wave-packet shows that a small amendment to the usual relativistic formalism can be helpful to demonstrate continuity with the non-relativistic case, although difficulties remain when the proposed quantum state has a broad relativistic energy distribution.

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Ahmed Roman, Asem Hassan, Mohamed ElKabbash

Thu Dec 15 2022 11:09:26 (2 days)

# 9.

Gravity is the weakest of all known forces. Measuring the gravitational force of micro and nano-scale source masses is an essential first step toward low-energy quantum gravity tests and searching for non-Newtonian gravity forces. Here, we propose an experiment using two optically trapped particles where the source mass is $\geq 10 fg$. In the proposed experiment, the optically levitated source mass is a rotating Janus particle leading to an amplified periodic oscillation of the test mass near resonance between Janus particle rotation frequency and the natural frequency of the test-mass trap. By tracking the motion of the test mass, it is possible to reach a signal-to-noise ratio greater than one for a Janus particle with a $100 nm$ radius within existing experimental capabilities of current levitation optodynamics experiments. The proposed experiment extends the search of Yukawa corrections to gravity down to $10^{-6}$ times gravity and opens the door to low energy tests for quantum gravity.

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Lorenzo Iorio

Thu Dec 15 2022 11:09:15 (2 days)

# 10.

Recently, Will calculated an additional contribution to the Mercury’s precession of the longitude of perihelion $\varpi$ of the order of $\dot\varpi_\textrm{W}\simeq 0.22$ $\textrm{milliarcseconds per century}$ ($\textrm{mas cty}^{-1}$). It is partly a direct consequence of certain 1pN third-body accelerations entering the planetary equations of motion, and partly an indirect, mixed effect due to the simultaneous interplay of the standard 1pN pointlike acceleration of the primary with the Newtonian $N$-body acceleration, to the quadrupole order, in the analytical calculation of the secular perihelion precession with the Gauss equations. We critically discuss the actual measurability of the mixed effects with respect to direct ones. The current uncertainties in either the magnitude of the Sun’s angular momentum $S_\odot$ and the orientation of its spin axis ${\boldsymbol{\hat{S}}}_\odot$ impact the precessions $\dot\varpi_{J_2^\odot},~\dot\varpi_\textrm{LT}$ induced by the Sun’s quadrupole mass moment and angular momentum via the Lense-Thirring effect to a level which makes almost impossible to measure $\dot\varpi_\textrm{W}$ even in the hypothesis that it comes entirely from the aforementioned 1pN third-body accelerations. On the other hand, from the point of view of the Lense-Thirring effect itself, the mismodeled quadrupolar precession $\delta\dot\varpi_{J_2^\odot}$ due to the uncertainties in ${\boldsymbol{\hat{S}}}_\odot$ corresponds to a bias of $\simeq 9\%$ of the relativistic one. The resulting simulated mismodeled range and range-rate times series of BepiColombo are at about the per cent level of the nominal gravitomagnetic ones.

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Thu Dec 15 2022 04:31:53 (3 days)

# 11.

Mitsch, Chris and Freeborn, David Peter Wallis and Gilton, Marian (2022) How Haag-tied is QFT, really? [Preprint]

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Zhi-Wei Wang, Samuel L. Braunstein

Wed Dec 14 2022 10:07:16 (3 days)

# 12.

Random sampling in high dimensions has successfully been applied to phenomena as diverse as nuclear resonances, neural networks and black hole evaporation. Here we revisit an elegant argument by the British physicist Dennis Sciama, which demonstrated that were our universe random, it would almost certainly have a negligible chance for life. Under plausible assumptions, we show that a random universe can masquerade as `intelligently designed,’ with the fundamental constants instead appearing to be fined tuned to achieve the highest probability for life to occur. For our universe, this mechanism may only require there to be around a dozen currently unknown fundamental constants. More generally, this mechanism appears to be important for data science analysis on constrained sets. Finally, we consider wider applications.

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Dimitry Leites

Wed Dec 14 2022 10:07:15 (3 days)

# 13.

Selected stories about the life of A. L. Onishchik, and a review of his contribution to the classification of non-split supermanifolds, in particular, supercurves a.k.a. superstrings; his editorial and educational work. A brief overview of his and his students’ results in supersymmetry, and their impact on other researchers.

Several open problems growing out of Onishchik’s research are presented, some of them are related with odd parameters of deformations and non-holonomic structures of supermanifolds important in physical models, such as Minkowski superspaces and certain superstrings.

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Wed Dec 14 2022 02:48:17 (4 days)

# 14.

Kareem Khalifa, Kareem and Lawler, Insa and Shech, Elay (2022) Introduction to the edited volume “Scientific Understanding and Representation: Modeling in the Physical Sciences”. Scientific Understanding and Representation: Modeling in the Physical Sciences.

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Olival Freire Junior

Tue Dec 13 2022 11:10:14 (4 days)

# 15.

Alain Aspect’s three experiments on Bell’s theorem, published in the early 1980s, were a turning point in the history of the research on the foundations of quantum mechanics not only because they corroborated entanglement as the distinctive quantum signature but also because these experiments brought wider recognition to this field of research and Aspect himself. These experiments may be considered the most direct precursors of the research on quantum information, which would blossom a decade later.

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Juliano C. S. Neves

Tue Dec 13 2022 11:10:13 (4 days)

# 16.

There have been three geometrizations in history. The first one is historically due to the Pythagorean school and Plato, the second one comes from Galileo, Kepler, Descartes and Newton, and the third is Einstein’s geometrization of nature. The term geometrization of nature means the conception according to which nature (with its different meanings) is massively described by using geometry. In this article, I focus on the third geometrization, in which the black hole shadow phenomenon provides an interesting statement about the level of geometrization achieved by the theory of general relativity. With the black hole shadow described by the Einsteinian theory, the geometrical interpretation of nature relates shape to dynamics or, more specifically, the shadow silhouette to the angular momentum, regardless the matter content inside the black hole. As a consequence, spacetime symmetry could play the role of the formal cause in black hole physics.

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Mon Dec 12 2022 10:35:35 (5 days)

# 17.

Dumitru, Spiridon (2005) On the uncertainty relations and quantum measurements: conventionalities, shortcomings, reconsiderations. [Preprint]

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Aihong Tang

Mon Dec 12 2022 08:00:00 (6 days)

# 18.

Nature Physics, Published online: 12 December 2022; doi:10.1038/s41567-022-01821-7

A potential observation of low-energy antihelium-3 nuclei would have profound impacts on our understanding of the Galaxy. Experiments at particle colliders help us understand how cosmic antimatter travels over long distances before reaching Earth.

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Sun Dec 11 2022 02:52:29 (1 week)

# 19.

Dorato, Mauro and Hoefer, Carl (2021) Nothing to Come in a relativistic setting. [Preprint]

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