| 上午9:55 | | | Jing-Hui Huang, Xue-Ying Duan, Fei-Fan He, Guang-Jun Wang, Xiang-Yun Hu | | | quant-ph updates on arXiv.org |
Weak measurement has enabled fundamental studies in both experiment and theory of quantum measurement. Numerous researches have indicated that weak measurements have a wide range of application and scientific research value. In our work, we used bibliometric methods to evaluate the global scientific output of research on Weak measurement and explore the current status and trends in this field from 2000 to 2020. The R bibliometric package was used for quantitative and qualitative analyses of publication outputs and author contributions. In total, 636 related articles and reviews were included in the final analysis. The main results were as follows: The number of publications has increased substantially with time. Physical Review A was the most active journal. The country and institution contributing the most to this field were The United States and University Rochester respectively. The analysis of the conceptual structure of keywords indicated that weak measurements were involved a variety of metrology, quantum communication, and nonclassical features of quantum mechanics. Our bibliometric analysis shows that weak measurement research continues to be a hot-spot. The focus has evolved to study quantum information and amplify weak signals.
Objective quantum fields, retrocausality and ontology. (arXiv:2108.11524v1 [quant-ph])
| 上午9:55 | | | Peter D Drummond, Margaret D Reid | | | quant-ph updates on arXiv.org |
We compare different approaches to quantum ontology. In particular, we discuss an interpretation of quantum mechanics that we call objective quantum field theory (OQFT), which involves retrocausal fields. Here, objective implies the existence of fields independent of an observer, but not that the results of conjugate measurements are predetermined: the theory is contextual. The ideas and analyses of Einstein and Bohr through to more recent approaches to objective realism are discussed. We briefly describe measurement induced projections, the guided wave interpretation, many-universes, consistent histories, and modal theories. These earlier interpretations are compared with OQFT. We argue that this approach is compatible both with Bohr’s quantum complementarity, and Einstein’s objective realism.
| 上午9:55 | | | physics.hist-ph updates on arXiv.org |
Authors: Slobodan Nedic
After some more than four centuries from the formulation and publication (in Astronomia Nova) of the Kepler’s Equation, which relates the eccentric (and, intermediately, the true) anomaly of the planetary trajectories to the uniformly flowing time, in accordance with his Second (“Area”) law, the subsequently — in course of development of Orbital Mechanics — to the 2nd law related and formally derived non-existent (zero-valued) transverse acceleration is questioned. Certain implications to Elliptic Integration, Symplectic Integration, Symplectic Geometry/Topology, as well as the connection between physical and mathematical continua in the context of the multi-level, scale-invariant mechanics/dynamics (with the augmented central and torquing forces) are also briefly hinted to.
Aether, Dark Energy, and String Compactifications. (arXiv:2108.07536v2 [hep-th] UPDATED)
| 上午9:55 | | | physics.hist-ph updates on arXiv.org |
Authors: Paul K. Townsend
The 19th century Aether died with Special Relativity but was resurrected by General Relativity in the form of dark energy; a tensile material with tension equal to its energy density. Such a material is provided by the D-branes of string-theory; these can support the fields of supersymmetric particle-physics, although their energy density is cancelled by orientifold singularities upon compactification. Dark energy can still arise from supersymmetry-breaking anti-D-branes but it is probably time-dependent. Recent results on time-dependent compactifications to an FLRW universe with late-time accelerated expansion are reviewed.
Machine learning accelerates quantum mechanics predictions of molecular crystals
| 上午9:54 | | | ScienceDirect Publication: Physics ReportsScienceDirect RSShttps://www.sciencedirect.com/journal/physics-reportsRSS for NodeTue, 23 Jul 2019 10:02:48 GMTCopyright © 2019 Elsevier B.V. All rights reservedRapid solidification as non-ergodic phenomenonPublication date: 20 July 2019Source: Physics Reports, Volume 818Author(s): P.K. Galenko, D. JouAbstractRapid solidification is a relevant physical phenomenon in material sciences, whose theoretical analysis requires going beyond the limits of local equilibrium statistical physics and thermodynamics and, in particular, taking account of ergodicity breaking and of generalized formulation of thermodynamics. The ergodicity breaking is related to the time symmetry breaking and to the presence of some kinds of fluxes and gradient flows making that an average of microscopic variables along time is different than an average over some chosen statistical ensemble. In fast processes, this is due, for instance, to the fact that the system has no time enough to explore the who |
Publication date: Available online 25 August 2021
Source: Physics Reports
Author(s): Yanqiang Han, Imran Ali, Zhilong Wang, Junfei Cai, Sicheng Wu, Jiequn Tang, Lin Zhang, Jiahao Ren, Rui Xiao, Qianqian Lu, Lei Hang, Hongyuan Luo, Jinjin Li
Neutrinos as a probe of curvature. (arXiv:2108.11423v1 [gr-qc])
| 上午9:54 | | | gr-qc updates on arXiv.org |
Authors: Jafar Khodagholizadeh
Neutrinos, as the anisotropic stress tensor, have a damping effect on the tensor mode perturbation from inflation to the $ \Lambda$ dominated era. First, we study the squared amplitude reduction for the wavelength entering the horizon during radiation and matter-dominated phases in the negatively curved de Sitter spacetime. Then, by comparing with other spatial spacetimes, $ K=0 $ and $K=1$, the highest difference between closed and open cases is seen in the matter-dominated era. Thus, neutrinos can be added as another candidate for determining the nature of space-time.
Weyl-invariant gravity. (arXiv:2108.11788v1 [gr-qc])
| 上午9:54 | | | gr-qc updates on arXiv.org |
Authors: Meir Shimon
A few implications of a classical Weyl-invariant scalar-tensor (WIST) version of general relativity (GR) are considered. This theory reduces to GR in a particular conformal frame in which the gravitational coupling and active gravitational masses are fixed. As an example, we recast the homogeneous and isotropic Friedmann-Robertson-Walker (FRW) spacetime in the WIST form with static space and monotonically evolving Planck mass. Cosmological redshift is then explained by the time-dependent lapse function. The latter is proportional to the shrinking (in this particular WIST frame) Planck length squared. The conformal Hubble expansion rate is replaced in this description by the logarithmic (conformal) time derivative of the Planck mass.
| 上午9:54 | | | gr-qc updates on arXiv.org |
Authors: Martin Bojowald
Background independence is often emphasized as an important property of a quantum theory of gravity that takes seriously the geometrical nature of general relativity. In a background-independent formulation, quantum gravity should determine not only the dynamics of space-time but also its geometry, which may have equally important implications for claims of potential physical observations. One of the leading candidates for background-independent quantum gravity is loop quantum gravity. By combining and interpreting several recent results, it is shown here how the canonical nature of this theory makes it possible to perform a complete space-time analysis in various models that have been proposed in this setting. In spite of the background-independent starting point, all these models turn out to be non-geometrical and even inconsistent to varying degrees, unless strong modifications of Riemannian geometry are taken into account. This outcome leads to several implications for potential observations as well as lessons for other background-independent approaches.
Indistinguishability and Negative Probabilities
| 上午12:16 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
de Barros, J. Acacio and Holik, Federico (2021) Indistinguishability and Negative Probabilities. Entropy. ISSN 1099-4300
| 上午12:10 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Ritson, Sophie (2021) Constraints and Divergent Assessments of Fertility in Non-empirical Physics in the History of the String Theory Controversy. [Preprint]
The Solution of the Paradox of Achilles and the Tortoise
| 2021年8月27日 星期五 上午4:03 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Gori, Giuseppe (2019) The Solution of the Paradox of Achilles and the Tortoise. Medium. pp. 1-4.
| 2021年8月26日 星期四 上午9:01 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Merritt, David (2020) Cosmological realism. [Preprint]
Taming conceptual wanderings: Wilson-Structuralism
| 2021年8月26日 星期四 上午8:00 | | | Latest Results for Synthese |
Abstract
Mark Wilson presents a highly original account of conceptual behavior that challenges many received views about concepts in analytic philosophy. Few attempts have been made to rationally reconstruct Wilson’s framework of patches and facades within a precise semantic framework. I will show how a modified version of the structuralist framework offers a semantic reconstruction of scientific theories capable of modeling Wilson’s ideas about conceptual behavior. Specifically, I will argue that Theory-Elements and a modified version of Theory-Nets explicate respectively Wilson’s patches and facades. I will also demonstrate how several wandering phenomena described by Wilson can be adequately reconstructed within my framework.
The Causal Structure of Reality
| 2021年8月25日 星期三 上午6:27 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Papineau, David (2021) The Causal Structure of Reality. [Preprint]
Trans-statistical behavior of a multiparticle system in an ontology of properties
| 2021年8月25日 星期三 上午6:25 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Pasqualini, Matias and Fortin, Sebastian (2021) Trans-statistical behavior of a multiparticle system in an ontology of properties. [Preprint]
The mereology of thermodynamic equilibrium
| 2021年8月24日 星期二 上午8:00 | | | Latest Results for Synthese |
Abstract
The special composition question (SCQ), which asks under which conditions objects compose a further object, establishes a central debate in modern metaphysics. Recent successes of inductive metaphysics, which studies the implications of the natural sciences for metaphysical problems, suggest that insights into the SCQ can be gained by investigating the physics of composite systems. In this work, I show that the minus first law of thermodynamics, which is concerned with the approach to equilibrium, leads to a new approach to the SCQ, the thermodynamic composition principle (TCP): Multiple systems in (generalized) thermal contact compose a single system. This principle, which is justified based on a systematic classification of possible mereological models for thermodynamic systems, might form the basis of an inductive argument for universalism. A formal analysis of the TCP is provided on the basis of mereotopology, which is a combination of mereology and topology. Here, “thermal contact” can be analyzed using the mereotopological predicate “self-connectedness”. Self-connectedness has to be defined in terms of mereological sums to ensure that scattered objects cannot be self-connected.
The Multiple-Computations Theorem and the physics of singling out a computation
| 2021年8月23日 星期一 下午2:23 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Shenker, Orly and Hemmo, Meir (2021) The Multiple-Computations Theorem and the physics of singling out a computation. [Preprint]
The indeterminacy of computation
| 2021年8月23日 星期一 上午8:00 | | | Latest Results for Synthese |
Abstract
Do the dynamics of a physical system determine what function the system computes? Except in special cases, the answer is no: it is often indeterminate what function a given physical system computes. Accordingly, care should be taken when the question ‘What does a particular neuronal system do?’ is answered by hypothesising that the system computes a particular function. The phenomenon of the indeterminacy of computation has important implications for the development of computational explanations of biological systems. Additionally, the phenomenon lends some support to the idea that a single neuronal structure may perform multiple cognitive functions, each subserved by a different computation. We provide an overarching conceptual framework in order to further the philosophical debate on the nature of computational indeterminacy and computational explanation.
On the Meaning of EPR’s Reality Criterion
| 2021年8月22日 星期日 上午1:22 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Gomori, Marton and Hofer-Szabó, Gábor (2021) On the Meaning of EPR’s Reality Criterion. [Preprint]
On The Anthropic Argument and The Fine-tuning Argument
| 2021年8月22日 星期日 上午1:20 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
Merriam, Paul (2021) On The Anthropic Argument and The Fine-tuning Argument. UNSPECIFIED.
Fair Infinite Lotteries, Qualitative Probability, and Regularity
| 2021年8月22日 星期日 上午1:19 | | | Philsci-Archive: No conditions. Results ordered -Date Deposited. |
DiBella, Nicholas (2021) Fair Infinite Lotteries, Qualitative Probability, and Regularity. [Preprint]
