Annals of Physics最新文献

{"title":"Geometric modeling of a line of alternating disclinations: Application to grain boundaries in graphene","authors":"A.M. de M. Carvalho ,&nbsp;C. Furtado","doi":"10.1016/j.aop.2025.170160","DOIUrl":"10.1016/j.aop.2025.170160","url":null,"abstract":"<div><div>We develop a conformal geometric model for grain boundaries in graphene based on a periodic line of alternating disclinations. Within the framework of <span><math><mrow><mo>(</mo><mn>2</mn><mo>+</mo><mn>1</mn><mo>)</mo></mrow></math></span>-dimensional gravity, we solve a reduced form of the Einstein equations to determine the conformal factor, from which the induced metric, scalar curvature, and holonomy are obtained analytically. Each pentagon–heptagon pair is modeled as a disclination dipole, forming a continuous distribution that captures the geometric signature of experimentally observed 5<span><math><mo>|</mo></math></span>7 grain boundaries. We show that the curvature is localized near the defect line and that the geometry becomes asymptotically flat, with trivial holonomy at large distances. This construction provides a tractable and physically consistent realization of the Katanaev–Volovich framework, connecting topological defect theory with atomistic features of graphene.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170160"},"PeriodicalIF":3.0,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724553","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}

{"title":"Exploring complexity in a Schwarzschild radiating star","authors":"Megandhren Govender,&nbsp;Wesley Govender","doi":"10.1016/j.aop.2025.170156","DOIUrl":"10.1016/j.aop.2025.170156","url":null,"abstract":"<div><div>We study the notion of complexity as defined by Herrera (L. Herrera, Phys. Rev. D <strong>97</strong>, 044010 (2018) <span><span>[1]</span></span>) in a collapsing Schwarzschild-like star. Starting off with the static Schwarzschild interior solution cast in isotropic coordinates, we allow the mass function to be time-dependent. This gives rise to a dynamical radiating sphere with isotropic pressure and heat flux in the stellar interior. Since the star is radiating energy, the exterior spacetime is described by the Vaidya solution. The initial static solution described by the interior Schwarzschild solution is complexity-free. As hydrostatic equilibrium is lost and the configuration collapses, it enters a dynamical phase which is also complexity-free. We show that in order for the complexity to vanish, the density inhomogeneity is balanced by heat dissipation at each interior point of the stellar configuration.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170156"},"PeriodicalIF":3.0,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722735","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}

{"title":"Wigner function for charged particles with spin 0 in non-commutative space","authors":"Dehong You,&nbsp;Yao Wang,&nbsp;Qi-Ming Fu,&nbsp;Junfeng He,&nbsp;Benzhuo Lou","doi":"10.1016/j.aop.2025.170154","DOIUrl":"10.1016/j.aop.2025.170154","url":null,"abstract":"<div><div>Wigner functions are quasi-probability distribution functions in phase space and play a crucial role in quantum optics, quantum information, and nuclear physics. In this paper,we first introduced the construction of the <span><math><msub><mrow><mo>⋆</mo></mrow><mrow><mi>θ</mi></mrow></msub></math></span>-product in non-commutative space and its relationship with the Wigner function. Then, we derived the eigenvalue equation of the Wigner function in non-commutative space using <span><math><msub><mrow><mo>⋆</mo></mrow><mrow><mi>θ</mi></mrow></msub></math></span>-product. Finally, we briefly discussed the role of <span><math><mi>θ</mi></math></span> in the observation of non-commutative effects in phase space within an electromagnetic field.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170154"},"PeriodicalIF":3.0,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144715751","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}

{"title":"Bulk viscous matter with decaying vacuum energy density: A model for late-time evolution of the Universe","authors":"Tanmay Nandi,&nbsp;Amitava Choudhuri","doi":"10.1016/j.aop.2025.170155","DOIUrl":"10.1016/j.aop.2025.170155","url":null,"abstract":"&lt;div&gt;&lt;div&gt;In this study, we combine viscous dark matter and running vacuum energy density in a single cosmological setting and investigate their cosmological implications. Specifically, we consider a well-studied form of running vacuum energy density model inspired by &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-gravity or, equivalently from the Brans–Dicke scalar-tensor theory that arises from a covariant action, i.e., &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ρ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;Λ&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̈&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mi&gt;λ&lt;/mi&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̇&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mi&gt;η&lt;/mi&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ρ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and a recently proposed general parameterization for bulk viscosity &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̇&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̈&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̇&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, where &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;λ&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;η&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;ζ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; are constants. In this setup, we derived analytical solutions for the Hubble parameter and the scale factor of the universe within the framework of Eckart’s theory of bulk viscosity. The viability of the proposed model equation is tested by constraining its free model parameters using the Hubble parameter &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;z&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and type Ia supernovae (SNe Ia) observations at different redshifts, and the goodness-of-fit of the model to the data was also checked by a &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;χ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; function minimization. Various significant cosmological parameters were estimated and analytically explained in the evolution dynamics of the universe, and a comparison of our proposed model with the &lt;span&gt;&lt;math&gt;&lt;mi&gt;Λ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;CDM model was studied. The application of dynamical systems analysis reveals the physical aspects of the new phase space that emerge from the model and deri","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170155"},"PeriodicalIF":3.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722734","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}

{"title":"Warp bubble geometries with anisotropic fluids: A piecewise analytical approach","authors":"N. Bolívar ,&nbsp;G. Abellán ,&nbsp;I. Vasilev","doi":"10.1016/j.aop.2025.170147","DOIUrl":"10.1016/j.aop.2025.170147","url":null,"abstract":"<div><div>We present a comprehensive analytical study of spherically symmetric warp bubble configurations in the framework of classical general relativity. We use a simplified ADM-type metric with a trivial lapse and a non-trivial radial shift function, which resembles a Painlevé–Gullstrand type metric. Employing this metric, our approach leads naturally to an anisotropic energy–momentum tensor characterized by an equation of state that emerges naturally from the equations. To reconcile the strict boundary conditions with the requirement of a localized matter distribution, we adopt a piecewise—defined model for the energy density. This construction allows us to confine possible violations of the dominant energy condition to finite and controlled shells, while ensuring that the weak and null energy conditions are globally satisfied. We illustrate our method with two representative examples: a one-shell exponential decay profile and a double-shell profile incorporating an additional power-law factor. Our results demonstrate that, by properly tuning the model parameters, it is possible to design warp bubble geometries that are not only mathematically consistent, but also physically more feasible, providing a promising stepping stone towards the development of realistic warp bubble models.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170147"},"PeriodicalIF":3.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724554","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}

{"title":"Alternative Frenkel liquid Lagrangian","authors":"F.A.P. Alves-Júnior ,&nbsp;A.S. Ribeiro ,&nbsp;G.B. Souza ,&nbsp;José A. Helayël-Neto","doi":"10.1016/j.aop.2025.170140","DOIUrl":"10.1016/j.aop.2025.170140","url":null,"abstract":"<div><div>Based on the Caldirola-Kanai approach, we endeavor to investigate a dissipative Lorentz Breaking scalar field theory in Minkowski space–time. We present its free-particle solutions for complex <span><math><msup><mrow><mi>ω</mi></mrow><mrow><mi>μ</mi></mrow></msup></math></span> components. We find three profiles of dispersion relations, two of them support gapped-momentum states. We also present an alternative view of this model, where dissipation acts as a geometric effect, and an effective negative scalar curvature space–time emerges. Finally, we also illustrate how the present model could be adapted to describe shear waves in Frenkel liquids and and its quantization process in order to compare with Trachenko’s original field theory.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170140"},"PeriodicalIF":3.0,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724552","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}

{"title":"Charged Zipoy–Voorhees metric in string theory","authors":"Odil Yunusov ,&nbsp;Bobur Turimov ,&nbsp;Yokubjon Khamroev ,&nbsp;Sulton Usanov ,&nbsp;Farkhodjon Turaev ,&nbsp;Markhabo Kuliyeva","doi":"10.1016/j.aop.2025.170151","DOIUrl":"10.1016/j.aop.2025.170151","url":null,"abstract":"<div><div>We have presented a solution for a charged Zipoy–Voorhees metric within the framework of low-energy effective field theory for heterotic string theory. This exact solution represents a deformed gravitational field in four-dimensional spacetime, characterized by three key parameters: the mass <span><math><mi>M</mi></math></span>, the electric charge <span><math><mi>Q</mi></math></span>, and the deformation parameter <span><math><mi>γ</mi></math></span>, which controls deviations from spherical symmetry. Unlike standard black hole solutions, this metric describes a naked singularity, meaning it lacks an event horizon and exposes the central singularity to external observers. To examine the physical properties of this spacetime, we analyzed the geodesic motion of test particles and photons. The study of geodesic trajectories provides insight into the effects of the deformation parameter <span><math><mi>γ</mi></math></span> and charged parameter <span><math><mrow><mi>b</mi><mo>=</mo><msup><mrow><mi>Q</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><mn>2</mn><mi>M</mi></mrow></math></span> on orbital motion, shadow, and potential astrophysical observables. Finally, a constraint on charge and deformation parameter using observed shadow radius of M87* has been obtained.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170151"},"PeriodicalIF":3.0,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724551","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}

{"title":"A note on a classical dynamical system and its quantization","authors":"F. Bagarello","doi":"10.1016/j.aop.2025.170145","DOIUrl":"10.1016/j.aop.2025.170145","url":null,"abstract":"<div><div>In a recent paper a slightly modified version of the Bateman system, originally proposed to describe a damped harmonic oscillator, was proposed. This system is really different from the Bateman’s one, in the sense that this latter cannot be recovered for any choice of its parameters. In this paper we consider this system and we show that, at a quantum level, it is not necessarily dissipative. In particular we show that the Hamiltonian of the system, when quantized, produces different behaviors, depending on some relations between its parameters. In fact, it gives rise to either a two dimensional (standard) harmonic oscillator, or to two independent oscillators, one of which is again <em>standard</em>, and a second one which is an inverted oscillator. The two cases are analyzed in terms of bosonic or pseudo-bosonic ladder operators, and the appearance of distributions for the inverted oscillator is commented.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170145"},"PeriodicalIF":3.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144678803","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}

{"title":"Quantum dynamics of curves on curved surfaces embedded in Euclidean space","authors":"Guo-Hua Liang ,&nbsp;Ai-Guo Mei ,&nbsp;Shu-Sheng Xu ,&nbsp;Meng-Yun Lai ,&nbsp;Hao Zhao","doi":"10.1016/j.aop.2025.170144","DOIUrl":"10.1016/j.aop.2025.170144","url":null,"abstract":"<div><div>Fabrication of one-dimensional curved waveguide on two-dimensional curved manifold may give an impetus to the investigation on new devices. Understanding how the combined geometric quantities of the curve and surface affect the quantum dynamics calls for an effective theory. Here, we delve into the effective Hamiltonian governing a quantum particle confined to a curve that lies on a curved surface. By categorizing the constraints, we derive the effective Hamiltonians for two distinct scenarios: one where the curve is encapsulated in the surface, and another where the curve is a narrow ridge on the surface. The surface’s geometry substantially influences the dynamics of the curve, with the gauge potential in the former case being proportional to the geodesic torsion, and the emerging surface geodesic potential in the latter case being determined by both the geodesic curvature and geodesic torsion. We apply both the Hamiltonians to model quantum dynamics in circles on a sphere and helices on a cylinder, analyzing how the effective potential varies with different geometric parameters. This research serves as a foundational reference for the design of future waveguides, offering insights into how to manipulate quantum states within curved nanostructures.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170144"},"PeriodicalIF":3.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144678804","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}

{"title":"Properties of compact objects in quadratic non-metricity gravity","authors":"G.G.L. Nashed ,&nbsp;Kazuharu Bamba","doi":"10.1016/j.aop.2025.170139","DOIUrl":"10.1016/j.aop.2025.170139","url":null,"abstract":"<div><div>Astrophysical compact objects are studied in the context of quadratic non-metricity gravity. The solutions to the gravitational field equations, which include fluid components, are analyzed to investigate the density and pressure properties of radio pulsars. It is explicitly demonstrated that the theoretically stable models are consistent with astronomical data, due to the geometric features of the quadratic component. Furthermore, it is shown that, in contrast to the compactness limits of black holes in general relativity, the core density can significantly exceed the density at which nuclear saturation occurs, and the surface density can also surpass the value of nuclear saturation. Additionally, it is found that the radial sound speed remains below the conformal upper bound for sound velocity established by perturbative quantum chromodynamics.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"481 ","pages":"Article 170139"},"PeriodicalIF":3.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686173","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}