https://doi.org/10.1140/epjc/s10052-020-8288-9
Letter
Causality of black holes in 4-dimensional Einstein–Gauss–Bonnet–Maxwell theory
1
Department of Physics, Shanghai University, Shanghai, 200444, China
2
Department of Physics, Hanyang University, Seoul, 133-791, South Korea
3
Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University, Yangzhou, 225009, China
* e-mail: gexh@shu.edu.cn
Received:
20
May
2020
Accepted:
26
July
2020
Published online:
3
August
2020
We study charged black hole solutions in 4-dimensional (4D) Einstein–Gauss–Bonnet–Maxwell theory to the linearized perturbation level. We first compute the shear viscosity to entropy density ratio. We then demonstrate how bulk causal structure analysis imposes an upper bound on the Gauss–Bonnet coupling constant in the AdS space. Causality constrains the value of Gauss–Bonnet coupling constant 
to be bounded by 
as 
.
© The Author(s), 2020
