修正Rastall引力中的黑洞时空

Black hole spacetime in generalized Rastall gravity

本文对Rastall引力理论进行了修正,并假设能动张量在弯曲时空中满足■传统的Rastall引力理论的具体假设条件有所不同,但是并不违背Rastall原有的理论思想.通过该假设我们得到了此修正引力理论中的静态带电黑洞解.在这个黑洞时空中,通过选择Rastall引力参数,可以得到Λ>0的Anti-de Sitter时空,或者Λ<0的de Sitter时空,甚至可以构造出没有引力常数的(Anti-)de Sitter时空.我们具体分析了n=1,2, 3三种情况下的球对称黑洞解的形式,并且通过调节λ得到各种不同类型的黑洞时空.我们的结果表明:在传统的Rastall引力理论中(n=1的情况),等效宇宙学常数的符号由Λ和λ同时决定;n=2时,我们发现即使Λ=0的情况下,我们依然有一个(Anti-)de Sitter解,这表明即使在Rastall理论中,(Anti-)de Sitter的真空黑洞解不一定依赖于宇宙常数存在与否,这有助于我们去理解暗能量的性质和Anti-de Sitter/共性场论(AdS/CFT)对应机制的物理本质.本文将对这几种时空进行具体分析.

This work generalizes the Rastall gravity and assumes that the energy momentum tensor satisfies the condition■The condition is different from the traditional Rastall gravity,but the generalized form does not contradict the basic idea of Rastall.Therefore,we obtain the gravitational field equation in generalized Rastall gravity and calculate the static charged spherical black hole solutions.The results show that in generalized Rastall gravity,Antide Sitter spacetime solution withΛ>0 and de Sitter spacetime withΛ<0 are possible.Furthermore,we also can get the asymptotic(Anti-)de Sitter black hole solution withΛ=0.We study the n=1,2,3 cases respectively,and get several black holes spacetimes by adjustingλ.It is found that the effective cosmological constant is determined by bothΛandλas n=1 case,while as n=2 case,the effective cosmological constant can still exist,even ifΛvanishes.The properties can help to understand the nature of dark energy and Anti-de Sitter/Conformal Field Theory(AdS/CFT)correspondence.We will investigate several properties of the black hole solutions in this work.