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Elmo Benedetto, Christian Corda, Ignazio Licata

Wed May 15 2024 11:34:05 (47 minutes)

# 1.

arXiv:2405.08024v1 Announce Type: new Abstract: Chae’s analyses on GAIA observations of wide binary stars have fortified the paradigm of extended gravity with particular attention to MOND-like theories. We recall that, starting from the origin of Einstein’s general relativity, the request of Mach on the structure of the theory has been the core of the foundational debate. This issue is strictly connected with the nature of the mass-energy equivalence. This was exactly the key point that Einstein used to derive the same general relativity. On the other hand, the current requirements of particle physics and the open questions within extended gravity theories, which have recently been further strengthened by analyses of GAIA observations, request a better understanding of the Equivalence Principle. By considering a direct coupling between the Ricci curvature scalar and the matter Lagrangian a non geodesic ratio between the inertial and the gravitational mass can be fixed and MOND-like theories are retrieved at low energies.

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Giorgio Torrieri

Wed May 15 2024 11:33:50 (47 minutes)

# 2.

arXiv:2405.08192v1 Announce Type: new Abstract: Assuming the validity of the equivalence principle in the quantum regime, we argue that one of the assumptions of the usual definition of quantum mechanics, namely separation between the “classical” detector and the “quantum” system, must be relaxed. We argue, therefore, that if both the equivalence principle and quantum mechanics continue to survive experimental tests, that this favors “epistemic” interpretations of quantum mechanics (where formalism is built around relations between observables) over “ontic ones” (assuming the reality of states and wavefunctions). In particular, we show that relational type interpretations can readily accomodate the equivalence principle via a minor modification of the assumptions used to justify the formalism. We qualitatively speculate what a full generally covariant quantum dynamics could look like, and comment on experimental investigations.

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Mon May 13 2024 17:17:29 (1 day)

# 3.

Laudisa, Federico (2024) Bohr and von Neumann on the Universality of Quantum Mechanics: Materials for the History of the Quantum Measurement Process. [Preprint]

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Frank Wilczek

Thu May 09 2024 08:07:32 (6 days)

# 4.

arXiv:2405.04565v1 Announce Type: cross Abstract: If we consider a cat to be an isolated mechanical system governed by T-invariant mechanics, then its ability to land on its feet after being released from rest is incomprehensible. It is more appropriate to treat the cat as a creature that can change its shape in order to accomplish a purpose. Within that framework we can construct a useful and informative of the observed motion. One can learn from this example.

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Brian C. Lacki

Thu May 09 2024 08:07:31 (6 days)

# 5.

arXiv:2106.07738v2 Announce Type: replace Abstract: Typicality arguments attempt to use the Copernican Principle to draw conclusions about the cosmos and presently unknown conscious beings within it, including extraterrestrial intelligences (ETI). The most notorious is the Doomsday Argument, which purports to constrain humanity’s future from its current lifespan alone. These arguments rest on a likelihood calculation that penalizes models in proportion to the number of distinguishable observers. I argue that such reasoning leads to solipsism, the belief that one is the only being in the world, and is therefore unacceptable. Using variants of the “Sleeping Beauty” thought experiment as a guide, I present a framework for evaluating observations in a large cosmos: Weighted Fine Graining (WFG). WFG requires the construction of specific models of physical outcomes and observations. Valid typicality arguments then emerge from the combinatorial properties of third-person physical microhypotheses. Indexical (observer-relative) facts do not directly constrain physical theories, but instead weight different provisional evaluations of credence. As indexical knowledge changes, the weights shift. I show that the self-applied Doomsday Argument fails in WFG, even though it can work for an external observer. I argue that the Copernican Principle does not let us apply self-observations to constrain ETIs.

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Gustavo Rigolin

Thu May 09 2024 06:00:00 (6 days)

# 6.

Author(s): Gustavo Rigolin

We show that the Schrödinger equation can be derived assuming the Galilean covariance of a generic wave equation and the validity of the de Broglie’s wave-particle duality hypothesis. We also obtain from this set of assumptions the transformation law for the wave function under a Galilean boost and …

[Phys. Rev. A 109, 052209] Published Thu May 09, 2024

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Wed May 08 2024 18:45:45 (6 days)

# 7.

de Ronde, Christian and Fernández Mouján, Raimundo and Massri, Cesar (2024) Everything is Entangled in Quantum Mechanics: Are the Orthodox Measures Physically Meaningful? [Preprint]

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Philippe Grangier

Tue May 07 2024 08:17:57 (1 week)

# 8.

arXiv:2405.03184v1 Announce Type: cross Abstract: In the foundations of quantum mechanics, the Kolmogorovian Censorship (KC) stipulates that quantum probabilities can be identified with classical, Kolmogorovian probabilities when considering a specified measurement context. Then in any given measurement context it is possible to build a Kolmogorovian probability distribution, or equivalently a hidden variable theory; however this distribution must be matched to the chosen context. In a loophole-free Bell test, the remote random choices of measurements (polarizers orientations) have the purpose to prevent that this matching can be obtained from any relativistically causal transmission between the source and the detectors. Then the matching (required to violate Bell’s inequalities) may be obtained either by an instantaneous influence at a distance between the source and the detectors (explicit nonlocality), or by assuming that it is pre-established before the actual experiment takes place (super-determinism). If both influence at a distance and super-determinism are not accepted on physical grounds, a third way is still available, called “predictive incompleteness”: it tells that the usual quantum state $\psi$ is incomplete, as long as the measurement context has not been specified. In agreement with the general quantum framework called CSM (Contexts, Systems and Modalities) we argue that predictive incompleteness is the correct quantum way to understand the violation of Bell’s inequalities.

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Jim Al-Khalili, Eddy Keming Chen

Tue May 07 2024 08:17:56 (1 week)

# 9.

arXiv:2405.03418v1 Announce Type: cross Abstract: If an asymmetry in time does not arise from the fundamental dynamical laws of physics, it may be found in special boundary conditions. The argument normally goes that since thermodynamic entropy in the past is lower than in the future according to the Second Law of Thermodynamics, then tracing this back to the time around the Big Bang means the universe must have started off in a state of very low thermodynamic entropy: the Thermodynamic Past Hypothesis. In this paper, we consider another boundary condition that plays a similar role, but for the decoherent arrow of time, i.e. the quantum state of the universe is more mixed in the future than in the past. According to what we call the Entanglement Past Hypothesis, the initial quantum state of the universe had very low entanglement entropy. We clarify the content of the Entanglement Past Hypothesis, compare it with the Thermodynamic Past Hypothesis, and identify some challenges and open questions for future research.