A consistent theory of D → 4 Einstein-Gauss-Bonnet gravity

被引：131

作者：

Aoki, Katsuki ^{[1
]}

Gorji, Mohammad Ali ^{[1
]}

Mukohyama, Shinji ^{[1
,2
]}

机构：

[1] Kyoto Univ, Ctr Gravitat Phys, Yukawa Inst Theoret Phys, Kyoto 6068502, Japan

[2] Univ Tokyo, Kavli Inst Phys & Math Universe WPI, Chiba 2778583, Japan

来源：

PHYSICS LETTERS B | 2020年 / 810卷

基金：

日本学术振兴会;

关键词：

D O I：

10.1016/j.physletb.2020.135843

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We investigate the D -> 4 limit of the D-dimensional Einstein-Gauss-Bonnet gravity, where the limit is taken with (alpha) over bar= ( D - 4) alpha kept fixed and a is the original Gauss-Bonnet coupling. Using the ADM decomposition in D dimensions, we clarify that the limit is rather subtle and ambiguous (if not ill-defined) and depends on the way how to regularize the Hamiltonian or/and the equations of motion. To find a consistent theory in 4 dimensions that is different from general relativity, the regularization needs to either break (a part of) the diffeomorphism invariance or lead to an extra degree of freedom, in agreement with the Lovelock theorem. We then propose a consistent theory of D -> 4 Einstein-Gauss-Bonnet gravity with two dynamical degrees of freedom by breaking the temporal diffeomorphism invariance and argue that, under a number of reasonable assumptions, the theory is unique up to a choice of a constraint that stems from a temporal gauge condition. (C) 2020 The Author(s). Published by Elsevier B.V.

引用

页数：6

共 29 条

[1] Causal field theory with an infinite speed of sound [J].