Covariant action for bouncing cosmologies in modified Gauss–Bonnet gravity

Abstract We examine holographic complexity in the doubly holographic model introduced in [1, 2] to study quantum extremal islands. We focus on the holographic complexity=volume (CV) proposal for boundary subregions in the island phase. Exploiting the Fefferman-Graham expansion of the metric and other geometric quantities near the brane, we derive the leading contributions to the complexity and interpret these in terms of the generalized volume of the island derived from the induced higher-curvature gravity action on the brane. Motivated by these results, we propose a generalization of the CV proposal for higher curvature theories of gravity. Further, we provide two consistency checks of our proposal by studying Gauss-Bonnet gravity and f(ℛ) gravity in the bulk.

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Flat self-dual gravity

Journal of High Energy Physics ◽

10.1007/jhep08(2021)082 ◽

2021 ◽

Vol 2021 (8) ◽

Author(s):

Kirill Krasnov ◽

Evgeny Skvortsov

Keyword(s):

Light Cone ◽

Space Time ◽

Kinetic Term ◽

Light Cone Gauge ◽

Yang Mills ◽

Covariant Action ◽

Chiral Interaction ◽

Double Copy

Abstract We construct a new covariant action for “flat” self-dual gravity in four space-time dimensions. The action has just one term, but when expanded around an appropriate background gives rise to a kinetic term and a cubic interaction. Upon imposing the light-cone gauge, the action reproduces the expected chiral interaction of Siegel. The new action is in many ways analogous to the known covariant action for self-dual Yang-Mills theory. There is also a sense in which the new self-dual gravity action exhibits the double copy of self-dual Yang-Mills structure.

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Magnetic-field effects on p-wave phase transition in Gauss–Bonnet gravity

International Journal of Modern Physics A ◽

10.1142/s0217751x14500948 ◽

2014 ◽

Vol 29 (20) ◽

pp. 1450094 ◽

Cited By ~ 11

Author(s):

Ya-Bo Wu ◽

Jun-Wang Lu ◽

Yong-Yi Jin ◽

Jian-Bo Lu ◽

Xue Zhang ◽

...

Keyword(s):

Magnetic Field ◽

Phase Transition ◽

P Wave ◽

Vector Model ◽

Magnetic Field Effects ◽

Complex Vector ◽

Bonnet Gravity ◽

Yang Mills ◽

Wave Phase ◽

Lowest Landau Level

In the probe limit, we study the holographic p-wave phase transition in the Gauss–Bonnet gravity via numerical and analytical methods. Concretely, we study the influences of the external magnetic field on the Maxwell complex vector model in the five-dimensional Gauss–Bonnet–AdS black hole and soliton backgrounds, respectively. For the two backgrounds, the results show that the magnetic field enhances the superconductor phase transition in the case of the lowest Landau level, while the increasing Gauss–Bonnet parameter always hinders the vector condensate. Moreover, the Maxwell complex vector model is a generalization of the SU(2) Yang–Mills model all the time. In addition, the analytical results backup the numerical results. Furthermore, this model might provide a holographic realization for the QCD vacuum instability.

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