中文
相关论文

相关论文: G\"odel's Universe and the Local Limit of Nonlocal…

200 篇论文

We investigate static spherically symmetric solutions within the framework of the local limit of nonlocal gravity. This theory departs from Einstein's general relativity (GR) through the introduction of a scalar gravitational susceptibility…

广义相对论与量子宇宙学 · 物理学 2025-09-25 Yahya Mohammadi , Javad Tabatabaei , Shant Baghram , Bahram Mashhoon

We consider nonlocal modification of the Einstein theory of gravity in framework of the pseudo-Riemannian geometry. The nonlocal term has the form $\mathcal{H}(R) \mathcal{F}(\Box)\mathcal {G}(R)$, where $\mathcal{H}$ and $\mathcal{G}$ are…

高能物理 - 理论 · 物理学 2015-08-25 Ivan Dimitrijevic , Branko Dragovich , Jelena Grujic , Zoran Rakic

In this paper we study G\"{o}del universe in the framework of $f(R,T)$ modified theories of gravity, where $R$ is the curvature scalar and $T$ the trace of the energy momentum tensor. We demonstrate that G\"{o}del solution occurs in this…

广义相对论与量子宇宙学 · 物理学 2015-06-16 A. F. Santos

In this paper, the G\"{o}del-type universes are examined within the framework of unimodular gravity. Since the existence of G\"{o}del solutions is intrinsically related to the presence of a cosmological constant in general relativity, one…

广义相对论与量子宇宙学 · 物理学 2025-06-16 R. Raimarda , A. F. Santos , R. Bufalo

The field equations of the recent nonlocal generalization of Einstein's theory of gravitation are presented in a form that is reminiscent of general relativity. The implications of the nonlocal field equations are studied in the case of…

广义相对论与量子宇宙学 · 物理学 2016-05-24 Donato Bini , Bahram Mashhoon

The Newtonian approximation with a nonvanishing nonlocal background field is analyzed for the scalar-tensor nonlocal gravity and nonlocal Gauss-Bonnet gravity. For these two theories, our calculations show that the Newtonian gravitational…

广义相对论与量子宇宙学 · 物理学 2019-03-28 S. X. Tian , Zong-Hong Zhu

There is ongoing interest in the nonmetricity formulation of gravity. The nonlinear extension of the theory, called $f(Q)$ gravity, has recently been proposed and offers a promising avenue for addressing some of the long-standing challenges…

广义相对论与量子宇宙学 · 物理学 2024-09-23 A. M. Silva , M. J. Rebouças , N. A. Lemos

The recent classical nonlocal generalization of Einstein's theory of gravitation is presented within the framework of general relativity via the introduction of a preferred frame field. The nonlocal generalization of Einstein's field…

广义相对论与量子宇宙学 · 物理学 2015-06-22 B. Mashhoon

G\"odel universe is a direct product of a line and a three-dimensional spacetime we call G$_\alpha$. In this paper, we show that the G\"odel metrics can arise as exact solutions in Einstein-Maxwell-Axion, Einstein-Proca-Axion, or…

高能物理 - 理论 · 物理学 2017-05-24 Shou-Long Li , Xing-Hui Feng , Hao Wei , H. Lu

[Abridged] In its standard formulation, the $f(T)$ field equations are not invariant under local Lorentz transformations, and thus the theory does not inherit the causal structure of special relativity. A locally Lorentz covariant $f(T)$…

广义相对论与量子宇宙学 · 物理学 2017-11-28 G. Otalora , M. J. Reboucas

Nonlocal gravity (NLG) is a classical nonlocal generalization of Einstein's theory of gravitation developed in close analogy with the nonlocal electrodynamics of media. It appears that the nonlocal aspect of the universal gravitational…

广义相对论与量子宇宙学 · 物理学 2022-09-12 Mahmood Roshan , Bahram Mashhoon

Within the framework of the local limit of nonlocal gravity (NLG), we investigate a class of Bianchi type I spatially homogeneous but anisotropic cosmological models. The modified field equations are presented in this case and some special…

广义相对论与量子宇宙学 · 物理学 2023-08-24 Javad Tabatabaei , Abdolali Banihashemi , Shant Baghram , Bahram Mashhoon

Nonlocal gravity is a promising super-renormalizable or finite quantum gravity theory consistent with unitarity. In this paper, we focus on the classical equations of motion and explicitly show that a particular subclass of G\"{o}del-type…

广义相对论与量子宇宙学 · 物理学 2026-05-05 Zhe Zhao , Leonardo Modesto , Cosimo Bambi

We present a class of generally covariant nonlocal gravity models which have a flat-space general relativistic (GR) limit and also possess a stable de Sitter (dS) or Anti-de Sitter (AdS) background with an arbitrary value of its…

高能物理 - 理论 · 物理学 2013-05-30 Andrei O. Barvinsky

The $f(R)$ gravity theories provide an alternative way to explain the current cosmic acceleration without a dark energy matter component. If gravity is governed by a $f(R)$ theory a number of issues should be reexamined in this framework,…

宇宙学与河外天体物理 · 物理学 2009-10-02 M. J. Reboucas , J. Santos

The analysis of measurements of accelerated observers in Minkowski spacetime has led to the development of nonlocal special relativity theory. Inertia and gravitation are intimately connected in accordance with the principle of equivalence.…

广义相对论与量子宇宙学 · 物理学 2012-10-11 Bahram Mashhoon

Rastall's theory is a generalization of Einstein's equations in which the energy-momentum tensor is not a conserved quantity, its covariant derivative is proportional to the gradient of the Ricci scalar and this fact can be associated with…

广义相对论与量子宇宙学 · 物理学 2015-03-05 A. F. Santos , S. C. Ulhoa

During hundred years of General Relativity (GR), many significant gravitational phenomena have been predicted and discovered. General Relativity is still the best theory of gravity. Nevertheless, some (quantum) theoretical and…

高能物理 - 理论 · 物理学 2017-01-10 Ivan Dimitrijevic , Branko Dragovich , Jelena Stankovic , Alexey S. Koshelev , Zoran Rakic

[Abridged] If gravitation is to be described by a hybrid metric-Palatini $f(\mathcal{R})$ gravity theory there are a number of issues that ought to be examined in its context, including the question as to whether its equations allow…

广义相对论与量子宇宙学 · 物理学 2018-07-17 Janilo Santos , Marcelo J. Reboucas , Antônio F. F. Teixeira

The Newtonian regime of a recent nonlocal extension of general relativity (GR) is investigated. Nonlocality is introduced via a scalar "constitutive" kernel in a special case of the translational gauge theory of gravitation, namely, the…

广义相对论与量子宇宙学 · 物理学 2010-04-29 Hans-Joachim Blome , Carmen Chicone , Friedrich W. Hehl , Bahram Mashhoon
‹ 上一页 1 2 3 10 下一页 ›