Foundations of Physics最新文献_第10页

On the Quasi-Separability of Atoms and Molecules 论原子和分子的准分离性

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-12-05 DOI: 10.1007/s10701-023-00736-4

Alejandro López-Castillo

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引用次数: 0

A Proposal for a New Kind of Spontaneous Collapse Model 关于新型自发坍塌模型的建议

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-12-05 DOI: 10.1007/s10701-023-00739-1

Nicolò Piccione

引用次数: 0

Physical Time and Human Time 物理时间和人类时间

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-11-29 DOI: 10.1007/s10701-023-00738-2

George F. R. Ellis

{"title":"Physical Time and Human Time","authors":"George F. R. Ellis","doi":"10.1007/s10701-023-00738-2","DOIUrl":"10.1007/s10701-023-00738-2","url":null,"abstract":"<div><p>This paper is a comment on both Bunamano and Rovelli (Bridging the neuroscience and physics of time arXiv:2110.01976. (2022)) and Gruber et al. (in Front. Psychol. Hypothesis Theory, 2022) and which discuss the relation between physical time and human time. I claim here, contrary to many views discussed there, that there is no foundational conflict between the way physics views the passage of time and the way the mind/brain perceives it. The problem rather resides in a number of misconceptions leading either to the representation of spacetime as a timeless Block Universe, or at least that physically relevant universe models cannot have preferred spatial sections. The physical expanding universe can be claimed to be an Evolving Block Universe with a time-dependent future boundary, representing the dynamic nature of the way spacetime develops as matter curves spacetime and spacetime tells matter how to move. This context establishes a global direction of time that determines the various local arrows of time. Furthermore time passes when quantum wave function collapse takes place to an eigenstate; during this process, information is lost. The mind/brain acts as an imperfect clock, which coarse-grains the physical passage of time along a world line to determine the experienced passage of time, because neural processes take time to occur. This happens in a contextual way, so experienced time is not linearly related to physical time in general. Finally I point out that the Universe is never infinitely old: its future endpoint always lies infinitely faraway in the future.</p></div>","PeriodicalId":569,"journal":{"name":"Foundations of Physics","volume":"54 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10701-023-00738-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138473324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Evading Quantum Mechanics à la Sudarshan: Quantum-Mechanics-Free Subsystem as a Realization of Koopman-von Neumann Mechanics 逃避量子力学:作为库普曼-冯·诺伊曼力学实现的无量子力学子系统

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-11-16 DOI: 10.1007/s10701-023-00734-6

Zurab K. Silagadze

引用次数: 0

Life, the Multiverse, and Fine-Tuning 生命、多元宇宙和微调

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-11-16 DOI: 10.1007/s10701-023-00732-8

Phillip Helbig

引用次数: 0

Can the Ontology of Bohmian Mechanics Consists Only in Particles? The PBR Theorem Says No 波米亚力学的本体论只能存在于粒子中吗？PBR定理说不

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-11-06 DOI: 10.1007/s10701-023-00731-9

Shan Gao

{"title":"Can the Ontology of Bohmian Mechanics Consists Only in Particles? The PBR Theorem Says No","authors":"Shan Gao","doi":"10.1007/s10701-023-00731-9","DOIUrl":"10.1007/s10701-023-00731-9","url":null,"abstract":"<div><p>The meaning of the wave function is an important unresolved issue in Bohmian mechanics. On the one hand, according to the nomological view, the wave function of the universe or the universal wave function is nomological, like a law of nature. On the other hand, the PBR theorem proves that the wave function in quantum mechanics or the effective wave function in Bohmian mechanics is ontic, representing the ontic state of a physical system in the universe. It is usually thought that the nomological view of the universal wave function is compatible with the ontic view of the effective wave function, and thus the PBR theorem has no implications for the nomological view. In this paper, I argue that this is not the case, and these two views are in fact incompatible. This means that if the effective wave function is ontic as the PBR theorem proves, then the universal wave function cannot be nomological, and the ontology of Bohmian mechanics cannot consist only in particles. This incompatibility result holds true not only for Humeanism and dispositionalism but also for primitivism about laws of nature, which attributes a fundamental ontic role to the universal wave function. Moreover, I argue that although the nomological view can be held by rejecting one key assumption of the PBR theorem, the rejection will lead to serious problems, such as that the results of measurements and their probabilities cannot be explained in ontology in Bohmian mechanics. Finally, I briefly discuss three <span>(psi)</span>-ontologies, namely a physical field in a fundamental high-dimensional space, a multi-field in three-dimensional space, and RDMP (Random Discontinuous Motion of Particles) in three-dimensional space, and argue that the RDMP ontology can answer the objections to the <span>(psi)</span>-ontology raised by the proponents of the nomological view.</p></div>","PeriodicalId":569,"journal":{"name":"Foundations of Physics","volume":"53 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71908821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Completely Discretized, Finite Quantum Mechanics 完全离散的有限量子力学

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-11-06 DOI: 10.1007/s10701-023-00726-6

Sean M. Carroll

引用次数: 0

Relaxation to Quantum Equilibrium and the Born Rule in Nelson’s Stochastic Dynamics 量子平衡的松弛与Nelson随机动力学中的Born规则

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-11-06 DOI: 10.1007/s10701-023-00730-w

Vincent Hardel, Paul-Antoine Hervieux, Giovanni Manfredi

{"title":"Relaxation to Quantum Equilibrium and the Born Rule in Nelson’s Stochastic Dynamics","authors":"Vincent Hardel, Paul-Antoine Hervieux, Giovanni Manfredi","doi":"10.1007/s10701-023-00730-w","DOIUrl":"10.1007/s10701-023-00730-w","url":null,"abstract":"<div><p>Nelson’s stochastic quantum mechanics provides an ideal arena to test how the Born rule is established from an initial probability distribution that is not identical to the square modulus of the wavefunction. Here, we investigate numerically this problem for three relevant cases: a double-slit interference setup, a harmonic oscillator, and a quantum particle in a uniform gravitational field. For all cases, Nelson’s stochastic trajectories are initially localized at a definite position, thereby violating the Born rule. For the double slit and harmonic oscillator, typical quantum phenomena, such as interferences, always occur well after the establishment of the Born rule. In contrast, for the case of quantum particles free-falling in the gravity field of the Earth, an interference pattern is observed <i>before</i> the completion of the quantum relaxation. This finding may pave the way to experiments able to discriminate standard quantum mechanics, where the Born rule is always satisfied, from Nelson’s theory, for which an early subquantum dynamics may be present before full quantum relaxation has occurred. Although the mechanism through which a quantum particle might violate the Born rule remains unknown to date, we speculate that this may occur during fundamental processes, such as beta decay or particle-antiparticle pair production.</p></div>","PeriodicalId":569,"journal":{"name":"Foundations of Physics","volume":"53 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71908819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Quantum and Relativistic Corrections to Maxwell–Boltzmann Ideal Gas Model from a Quantum Phase Space Approach 从量子相空间方法对麦克斯韦-玻尔兹曼理想气体模型的量子和相对论修正

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-10-03 DOI: 10.1007/s10701-023-00727-5

Rivo Herivola Manjakamanana Ravelonjato, Ravo Tokiniaina Ranaivoson, Raoelina Andriambololona, Roland Raboanary, Hanitriarivo Rakotoson, Naivo Rabesiranana

{"title":"Quantum and Relativistic Corrections to Maxwell–Boltzmann Ideal Gas Model from a Quantum Phase Space Approach","authors":"Rivo Herivola Manjakamanana Ravelonjato, Ravo Tokiniaina Ranaivoson, Raoelina Andriambololona, Roland Raboanary, Hanitriarivo Rakotoson, Naivo Rabesiranana","doi":"10.1007/s10701-023-00727-5","DOIUrl":"10.1007/s10701-023-00727-5","url":null,"abstract":"<div><p>The quantum corrections related to the ideal gas model often considered are those associated to the bosonic or fermionic nature of particles. However, in this work, other kinds of corrections related to the quantum nature of phase space are highlighted. These corrections are introduced as improvements in the expression of the partition function of an ideal gas. Then corrected thermodynamics properties of the ideal gas are deduced. Both the non-relativistic quantum and relativistic quantum cases are considered. It is shown that the corrections in the non-relativistic quantum case may be particularly useful to describe the deviation from the Maxwell–Boltzmann model at low temperature and/or in confined space. These corrections can be considered as including the description of quantum size and shape effects. For the relativistic quantum case, the corrections could be relevant for confined space and when the thermal energy of each particle is comparable to their rest energy. The corrections appear mainly as modifications in the thermodynamic equation of state and in the expressions of the partition function and thermodynamic functions like entropy, internal energy and free energy. Expressions corresponding to the Maxwell–Boltzmann model are shown to be asymptotic limits of the corrected expressions.</p></div>","PeriodicalId":569,"journal":{"name":"Foundations of Physics","volume":"53 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134795365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Is Superluminal Signaling Possible in Collapse Theories of Quantum Mechanics? 量子力学坍缩理论中可能存在超光速信号吗?

IF 1.5 3区物理与天体物理

Foundations of Physics Pub Date : 2023-09-23 DOI: 10.1007/s10701-023-00729-3

Shan Gao

引用次数: 0