arXiv - PHYS - General Physics最新文献_第4页

Diffeomorphism Invariance and General Relativity 衍射不变性与广义相对论

arXiv - PHYS - General Physics Pub Date : 2024-07-07 DOI: arxiv-2407.16702

Max Heitmann

{"title":"Diffeomorphism Invariance and General Relativity","authors":"Max Heitmann","doi":"arxiv-2407.16702","DOIUrl":"https://doi.org/arxiv-2407.16702","url":null,"abstract":"Diffeomorphism invariance is often considered to be a hallmark of the theory\u0000of general relativity (GR). But closer analysis reveals that this cannot be\u0000what makes GR distinctive. The concept of diffeomorphism invariance can be\u0000defined in two ways: under the first definition (diff-invariance$_1$), both GR\u0000and all other classical spacetime theories turn out to be diffeomorphism\u0000invariant, while under the second (diff-invariance$_2$), neither do. Confusion\u0000about the matter can be traced to two sources. First, GR is sometimes\u0000erroneously thought to embody a \"general principle of relativity,\" which\u0000asserts the relativity of all states of motion, and from which it would follow\u0000that GR must be diff-invariant$_2$. But GR embodies no such principle, and is\u0000easily seen to violate diff-invariance$_2$. Second, GR is unique among\u0000spacetime theories in requiring a general-covariant formulation, whereas other\u0000classical spacetime theories are typically formulated with respect to a\u0000preferred class of global coordinate systems in which their dynamical equations\u0000simplify. This makes GR's diffeomorphism invariance (in the sense of\u0000diff-invariance$_1$) manifest, while in other spacetime theories it lies latent\u0000-- at least in their familiar formulations. I trace this difference back to the\u0000fact that the spacetime structure is inhomogeneous within the models of GR, and\u0000mutable across its models. I offer a formal criterion for when a spacetime\u0000theory possesses immutable spacetime structure, and using this criterion I\u0000prove that a theory possesses a preferred class of coordinate systems\u0000applicable across its models if and only if it possesses immutable spacetime\u0000structure.","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141785130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Finite Algebraic Quantum Field Theory 有限代数量子场论

arXiv - PHYS - General Physics Pub Date : 2024-07-07 DOI: arxiv-2407.14524

A. D. Alhaidari

引用次数: 0

Tiling Spaces and the Expanding Universe: Bridging Quantum Mechanics and Cosmology 平铺空间与膨胀的宇宙：连接量子力学与宇宙学

arXiv - PHYS - General Physics Pub Date : 2024-07-05 DOI: arxiv-2407.14520

Aman Yadav, Marcelo Maciel Amaral

{"title":"Tiling Spaces and the Expanding Universe: Bridging Quantum Mechanics and Cosmology","authors":"Aman Yadav, Marcelo Maciel Amaral","doi":"arxiv-2407.14520","DOIUrl":"https://doi.org/arxiv-2407.14520","url":null,"abstract":"We propose a heuristic model of the universe as a growing quasicrystal\u0000projected from a higher-dimensional lattice. By extending the Schr\"{o}dinger\u0000equation for a particle in a box with time-dependent boundaries, we derive an\u0000equation that resembles the Friedmann equation, addressing the Hubble tension.\u0000This model incorporates phonons and phasons, providing insights into\u0000cosmic-scale dynamics and the universe's expansion. We outline a pre-inflation\u0000tiling space phase with quantum error correction, a radiation phase dominated\u0000by quasiparticles, and a post-radiation phase with the emergence of matter. Our\u0000hypothesis, which posits that the universe is a growing quasicrystal, suggests\u0000that the necessity for an inflationary period may be obviated. Furthermore,\u0000phonon arising from this quasicrystalline structure could act as dark matter,\u0000influencing the dynamics of ordinary matter while remaining mostly undetectable\u0000by electromagnetic interactions. This hypothesis draws parallels with other\u0000crystalline matter at atomic scales that are fundamentally quantum in nature.\u0000We also explore how the notion of tiling space can support continuous symmetry\u0000atop a discrete structure, providing a novel framework for understanding the\u0000universe's expansion and underlying structure. Consequently, it is logical to\u0000start with quantum mechanics as the foundation of our model. Further\u0000development could enhance our understanding of cosmic expansion and the\u0000underlying structure of the universe.","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"349 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Crystalline Vacuum as the Background of the Standard Model 晶体真空作为标准模型的背景

arXiv - PHYS - General Physics Pub Date : 2024-07-04 DOI: arxiv-2407.16700

L. M. Pismen

引用次数: 0

Integrated Deflector Shield Technology for Spacecraft 航天器集成偏转护盾技术

arXiv - PHYS - General Physics Pub Date : 2024-07-04 DOI: arxiv-2407.16701

Florian Neukart

{"title":"Integrated Deflector Shield Technology for Spacecraft","authors":"Florian Neukart","doi":"arxiv-2407.16701","DOIUrl":"https://doi.org/arxiv-2407.16701","url":null,"abstract":"The increasing velocity and frequency of space missions necessitate\u0000advancements in spacecraft protection technologies to ensure mission success\u0000and the safety of onboard systems and personnel. Existing shielding solutions,\u0000including electromagnetic shields, plasma shields, and speculative force\u0000fields, each offer distinct protective capabilities but are limited when used\u0000independently. This study proposes an integrated deflector shield system that\u0000combines the strengths of these technologies to provide comprehensive\u0000protection against a wide range of spaceborne threats, including charged\u0000particles, micrometeoroids, and high-energy radiation. By leveraging fusion\u0000energy as a primary power source, we aim to sustain a high-energy shield\u0000capable of dynamically adjusting to varying threat levels. Extensive\u0000theoretical modeling, simulations, and analytical calculations demonstrate the\u0000feasibility of this integrated approach, highlighting significant improvements\u0000in energy efficiency and scalability. The implementation of this multi-layered\u0000shield system marks a pivotal advancement in spacecraft protection, paving the\u0000way for safer and more reliable space exploration missions.","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Constraints on the time variation of $c$ and $G$ from Dark Energy Survey Snpernova Program 暗能量巡天超新星计划对 $c$ 和 $G$ 时间变化的约束

arXiv - PHYS - General Physics Pub Date : 2024-06-25 DOI: arxiv-2407.09532

Seokcheon Lee

{"title":"Constraints on the time variation of $c$ and $G$ from Dark Energy Survey Snpernova Program","authors":"Seokcheon Lee","doi":"arxiv-2407.09532","DOIUrl":"https://doi.org/arxiv-2407.09532","url":null,"abstract":"In the context of the dispersion relation $c = lambda nu$ and considering\u0000an expanding universe where the observed wavelength today is redshifted from\u0000the emitted wavelength by $lambda_{0} = lambda_{text{emit}} (1+z)$, to keep\u0000$c$ constant, it must be that $nu_{0} = nu_{text{emit}} /(1+z)$. However,\u0000although the theory for wavelength in the RW metric includes the cosmological\u0000redshift, the same is not simply deduced for frequency (the inverse of time).\u0000Instead, cosmological time dilation $T_{0} = T_{text{emit}} (1+z)$ is an\u0000additional assumption made to uphold the hypothesis of constant speed of light\u0000rather than a relation directly derived from the RW metric. Therefore,\u0000verifying cosmological time dilation observationally is crucial. The most\u0000recent data employing supernovae for this purpose was released recently by the\u0000Dark Energy Survey. Results from the i-band specifically support variations in\u0000the speed of light within 1-$sigma$. We used these observations to investigate\u0000variations in various physical quantities, including $c$ and $G$, using the\u0000minimally extended varying speed of light model. The speed of light was $0.4$%\u0000to $2.2$% slower, and Newton's constant may have decreased by $1.7$% to\u0000$8.4$% compared to their current values at redshift $2$. These findings,\u0000consistent with previous studies, hint at resolving tensions between different\u0000$Lambda$CDM cosmological backgrounds but are not yet conclusive evidence of a\u0000varying speed of light, as the full-band data aligns with standard model\u0000cosmology.","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141720948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wide Binaries, Retardation and the External Field Effect 宽双星、迟滞和外场效应

arXiv - PHYS - General Physics Pub Date : 2024-06-19 DOI: arxiv-2406.15497

Asher Yahalom

{"title":"Wide Binaries, Retardation and the External Field Effect","authors":"Asher Yahalom","doi":"arxiv-2406.15497","DOIUrl":"https://doi.org/arxiv-2406.15497","url":null,"abstract":"A low acceleration gravitational anomaly was reported for wide binaries: two\u0000binary stars which are separated by more than five kilo astronomical units\u0000(kau). The increase in gravitational force was reported to be about $1.37$\u0000greater than Newtonian gravity. At the same time binaries separated less than\u0000one kau were shown to obey standard Newtonian gravity. A possible explanation\u0000for this was given in the framework of MOND correction to gravity which is\u0000applicable for low acceleration. However, it was noticed that the explanation\u0000is only adequate in the framework of Milgromian AQUAL theory which considers\u0000the \"external field effect\" that is the effect of the gravitational field of\u0000the rest of the galaxy on the binary system. Recently it was shown that many\u0000\"anomalous gravity\" effects can be explained in the framework of general\u0000relativity and its weak field approximation. It was shown that anomalous galaxy\u0000rotation curves, anomalous gravitational lensing and the Tully-Fisher relations\u0000can be understood in terms of retarded gravity. Moreover, the anomalous mass of\u0000galaxy clusters derived from the virial theorem was also shown to be a retarded\u0000gravity effect. On the other hand, it was shown that retarded effects are not\u0000important in the solar system and the correction to the anomalous shift of\u0000Mercury's perihelion is connected with the motion of the solar center of mass\u0000with respect to the sun and not to retardation. It is desirable to investigate\u0000if the wide binary acceleration gravitational anomaly can be explained in the\u0000framework of Einstein-Newton general relativity. We show that the scale of five\u0000kau separation arises naturally within such a theory if the effect of the\u0000galaxy on the wide binary is considered (a Newtonian external field effect)\u0000suggesting the anomaly found can be explained without the need to invoke\u0000theoretical modifications of the accepted theory.","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Considerations about the measurement of the magnetic moment and electric dipole moment of the electron 测量电子磁矩和电偶极矩的注意事项

arXiv - PHYS - General Physics Pub Date : 2024-06-19 DOI: arxiv-2406.15502

Martin Rivas

{"title":"Considerations about the measurement of the magnetic moment and electric dipole moment of the electron","authors":"Martin Rivas","doi":"arxiv-2406.15502","DOIUrl":"https://doi.org/arxiv-2406.15502","url":null,"abstract":"The goal of the measurement of the magnetic moment of the electron $mu$, is\u0000to experimentaly determine the gyromagnetic ratio. The factor $g/2$ is computed\u0000by the accurate measurement of two frequencies, the spin precession frequency\u0000$nu_s$, and the cyclotron frequency $nu_c$, and is defined as\u0000$nu_s/nu_c=g/2$. These experiments are performed with a single electron\u0000confined inside a Penning trap. The existence of the electric dipole moment\u0000${d}_e$, involves the idea of an asymmetric charge distribution along the spin\u0000direction such that ${ d}_e=d_e{ S}/(hbar/2)$. The energy shift $Delta\u0000U=2{d}_eE_{eff}$ of the interaction of the electric dipole of electrons with a\u0000huge effective electric field ${E}_{eff}$, close to the nucleus of heavy\u0000neutral atoms or molecules, is determined by a spin precession measurement. By\u0000using a classical model of a spinning electron, which satisfies Dirac's\u0000equation when quantized, we determine classically the time average value of the\u0000electric and magnetic dipole moments of this electron model when moving in a\u0000uniform magnetic field and in a Penning trap, with the same fields as in the\u0000real experiments, and obtain an estimated value of these dipoles. We compare\u0000these results with the experimental data and make some interpretation of the\u0000measured dipoles.","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Brownian Motion of the Quantum States on a String and the Polyakov Action of String Theory: Is String Theory a Quantum Mechanical Model of the Brain? 弦上量子态的布朗运动与弦理论的波利亚可夫作用：弦理论是大脑的量子力学模型吗？

arXiv - PHYS - General Physics Pub Date : 2024-06-16 DOI: arxiv-2406.12932

Amir Abbass Varshovi

{"title":"Brownian Motion of the Quantum States on a String and the Polyakov Action of String Theory: Is String Theory a Quantum Mechanical Model of the Brain?","authors":"Amir Abbass Varshovi","doi":"arxiv-2406.12932","DOIUrl":"https://doi.org/arxiv-2406.12932","url":null,"abstract":"The Brownian motion of a number of quantum states in a compact\u0000one-dimensional space is studied via the Wiener fractal measure, and it is\u0000shown that the derived path-integral measure coincides precisely with the\u0000Polyakov path-integral formula for bosonic string theory. Thus, it is concluded\u0000that the Polyakov action of bosonic string theory does not have a unique,\u0000distinguishable foundation specifically dedicated to describing the fundamental\u0000forces of nature, but rather, it is merely a standard formulation of the Wiener\u0000stochastic process for Brownian motion of the quantum states on one-dimensional\u0000objects. It is also demonstrated that the time-dimension field is, in practice,\u0000the localization of the non-local effects of the coordinate fields. This\u0000indicates that the interpretation intended for spacetime fields in the\u0000formulation of string theory allegedly faces fundamental flaws in its\u0000underlying theoretical aspects. In this regard, we will defend string theory\u0000against its experimental flaws in particle physics due to unreliable\u0000interpretation of the theory and relate its elaborated mathematical framework\u0000to another significant topic: Quantum Brain. ....","PeriodicalId":501190,"journal":{"name":"arXiv - PHYS - General Physics","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spin Entanglement -- A Unifying Principle for Superconductors and Molecular Bonding 自旋纠缠--超导体和分子结合的统一原理

arXiv - PHYS - General Physics Pub Date : 2024-06-13 DOI: arxiv-2406.09482

Paul O'Hara

引用次数: 0