Can a variation of fine structure constant influence the fate of gravitational collapse?

IF 4.2 2区物理与天体物理 Q2 PHYSICS, PARTICLES & FIELDS

The European Physical Journal C Pub Date : 2023-08-05 DOI:10.1140/epjc/s10052-023-11877-1

Soumya Chakrabarti

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引用次数: 1

Abstract

We show that it is possible to steer clear of a spacetime singularity during gravitational collapse by considering time-variation of a fundamental coupling, in this case, the fine structure constant \(\alpha \). We study a spherical distribution of cold dark matter coexisting with other fluid elements, collapsing under its own gravity. The dark matter is written as a scalar field interacting with electrically charged matter. This leads to a time variation of \(\alpha \) and as a consequence, a breakdown of local charge conservation within the sphere. The exterior has no such field and therefore, Einstein’s GR and standard equivalence principles remain valid. We derive the lowest possible bound on the collapse of this sphere beyond which there is a bounce and dispersal of most of the accumulated matter. We discuss the critical behavior of the system around this point and show that the bound is connected to a length scale of the order of Planck, introduced in the theory for dimensional requirements.

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精细结构常数的变化会影响引力坍缩的命运吗?

我们表明，通过考虑基本耦合的时间变化，在这种情况下，精细结构常数\(\alpha \)，有可能在引力坍缩期间避开时空奇点。我们研究了冷暗物质与其他流体元素共存，在自身重力作用下坍缩的球形分布。暗物质被描述为与带电物质相互作用的标量场。这导致了\(\alpha \)的时间变化，结果导致了球内局部电荷守恒的破坏。外部没有这样的场，因此，爱因斯坦的广义相对论和标准等效原理仍然有效。我们推导出这个球体坍缩的最低可能边界，超过这个边界，大多数积累的物质就会反弹和分散。我们讨论了系统在这一点周围的临界行为，并表明该边界与普朗克数量级的长度尺度有关，这是在理论中为满足尺寸要求而引入的。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

The European Physical Journal C 物理-物理：粒子与场物理

CiteScore

8.10

自引率

15.90%

发文量

1008

审稿时长

2-4 weeks

期刊介绍： Experimental Physics I: Accelerator Based High-Energy Physics Hadron and lepton collider physics Lepton-nucleon scattering High-energy nuclear reactions Standard model precision tests Search for new physics beyond the standard model Heavy flavour physics Neutrino properties Particle detector developments Computational methods and analysis tools Experimental Physics II: Astroparticle Physics Dark matter searches High-energy cosmic rays Double beta decay Long baseline neutrino experiments Neutrino astronomy Axions and other weakly interacting light particles Gravitational waves and observational cosmology Particle detector developments Computational methods and analysis tools Theoretical Physics I: Phenomenology of the Standard Model and Beyond Electroweak interactions Quantum chromo dynamics Heavy quark physics and quark flavour mixing Neutrino physics Phenomenology of astro- and cosmoparticle physics Meson spectroscopy and non-perturbative QCD Low-energy effective field theories Lattice field theory High temperature QCD and heavy ion physics Phenomenology of supersymmetric extensions of the SM Phenomenology of non-supersymmetric extensions of the SM Model building and alternative models of electroweak symmetry breaking Flavour physics beyond the SM Computational algorithms and tools...etc.