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引用次数: 0
摘要
我们提出了一种双参数、静态和球面对称的规则几何,它在特定参数值下代表了一个规则黑洞。我们发现,在广义相对论(GR)框架内支持这种时空所需的物质违反了能量条件,尽管不是在整个径向坐标域。参数的特定选择将规则黑洞简化为奇异的、变异的赖斯纳-诺德斯特伦几何。事实还证明,我们的规则黑洞在测地上是完整的。幸运的是,尽管违反了能量条件,我们还是能够在与物质耦合的 GR 框架内,为我们的规则几何构造出一个可行的源。这个源项涉及非线性电动力学版本中的一个非线性磁单极。我们还提出了另一种构建源的方法,即使用在支链世界引力背景下产生的有效爱因斯坦方程。最后,我们得到了规则黑洞的圆影轮廓,并利用 EHT 合作项目的最新观测结果对度量参数进行了初步估算。
Novel regular black holes: geometry, source and shadow
We propose a two-parameter, static and spherically symmetric regular geometry, which, for specific parameter values represents a regular black hole. The matter required to support such spacetimes within the framework of general relativity (GR), is found to violate the energy conditions, though not in the entire domain of the radial coordinate. A particular choice of the parameters reduces the regular black hole to a singular, mutated Reissner–Nordström geometry. It also turns out that our regular black hole is geodesically complete. Fortunately, despite energy condition violation, we are able to construct a viable source, within the framework of GR coupled to matter, for our regular geometry. The source term involves a nonlinear magnetic monopole in a chosen version of nonlinear electrodynamics. We also suggest an alternative approach towards constructing a source, using the effective Einstein equations which arise in the context of braneworld gravity. Finally, we obtain the circular shadow profile of our regular black hole and provide a preliminary estimate of the metric parameters using recent observational results from the EHT collaboration.
期刊介绍:
General Relativity and Gravitation is a journal devoted to all aspects of modern gravitational science, and published under the auspices of the International Society on General Relativity and Gravitation.
It welcomes in particular original articles on the following topics of current research:
Analytical general relativity, including its interface with geometrical analysis
Numerical relativity
Theoretical and observational cosmology
Relativistic astrophysics
Gravitational waves: data analysis, astrophysical sources and detector science
Extensions of general relativity
Supergravity
Gravitational aspects of string theory and its extensions
Quantum gravity: canonical approaches, in particular loop quantum gravity, and path integral approaches, in particular spin foams, Regge calculus and dynamical triangulations
Quantum field theory in curved spacetime
Non-commutative geometry and gravitation
Experimental gravity, in particular tests of general relativity
The journal publishes articles on all theoretical and experimental aspects of modern general relativity and gravitation, as well as book reviews and historical articles of special interest.