论文标题
电磁通用准则重力为$(2 + 1)$尺寸
Electromagnetic Generalized Quasi-topological gravities in $(2 + 1)$ dimensions
论文作者
论文摘要
在三维中的准居民重力构建需要将标量场耦合到度量标准。如Arxiv:2104.10172所示,由此产生的“电磁”准平原(EQT)理论接纳了带电的黑洞解决方案,其特征在于公制的单功能,$ -g_ {tt} = g^g^{ - 1} _ { - {rr} _ {rr} _ {rr} _ {rr} \ equiv f(rr)这样的黑洞可以通过各种方式进行全面分析确定的公制,包括无奇异的黑洞,而无需对耦合或参数进行任何微调。在本文中,我们将EQT理论的家族延伸到一般曲率顺序。我们表明,除线性顺序外,$ f(r)$满足二阶差分方程而不是代数方程式,使相应的理论属于电磁通用准论(EGQT)类。我们证明,在每个曲率顺序上,最通用的EGQT密度是由单个项给出的,该术语对$ f(r)$加密的方程式无效,而密度也根本不影响该方程。证明依赖于$ \ Mathcal {l}(r_ {ab},\ partial_a ϕ)$的独立订单的确切数量的计数。我们研究了EGQT黑洞溶液的新家族的一些一般方面,包括其热力学特性和对第一定律的实现,并明确构建了其中一些。
The construction of Quasi-topological gravities in three-dimensions requires coupling a scalar field to the metric. As shown in arXiv:2104.10172, the resulting "Electromagnetic" Quasi-topological (EQT) theories admit charged black hole solutions characterized by a single-function for the metric, $-g_{tt}=g^{-1}_{rr}\equiv f(r)$, and a simple azimuthal form for the scalar. Such black holes, whose metric can be determined fully analytically, generalize the BTZ solution in various ways, including singularity-free black holes without any fine-tuning of couplings or parameters. In this paper we extend the family of EQT theories to general curvature orders. We show that, beyond linear order, $f(r)$ satisfies a second-order differential equation rather than an algebraic one, making the corresponding theories belong to the Electromagnetic Generalized Quasi-topological (EGQT) class. We prove that at each curvature order, the most general EGQT density is given by a single term which contributes nontrivially to the equation of $f(r)$ plus densities which do not contribute at all to such equation. The proof relies on the counting of the exact number of independent order-$n$ densities of the form $\mathcal{L}(R_{ab},\partial_a ϕ)$, which we carry out. We study some general aspects of the new families of EGQT black-hole solutions, including their thermodynamic properties and the fulfillment of the first law, and explicitly construct a few of them numerically.