Surface Terms of Quintic Quasitopological Gravity and Thermodynamics of Quasi-Topological Magnetic Brane Coupled to Nonlinear Electrodynamics

TL;DR

This paper introduces a surface term for quintic quasitopological gravity to ensure a well-defined action, and explores numerical solutions coupled with nonlinear electrodynamics, revealing conical singularities and finite conserved quantities.

Contribution

It provides a new surface term for the quintic quasitopological gravity action and analyzes numerical solutions with nonlinear electrodynamics, including divergence removal techniques.

Findings

Surface term makes the action well-defined for flat boundaries.

Solutions exhibit conical singularity at the origin.

Counterterm yields finite conserved quantities.

Abstract

For the the quintic quasitopological action which has no well-defined variational principle, we introduced a surface term that for a spacetime with flat boundaries make the action well-defined. Moreover, we investigated the numerical solutions of the above-mentioned gravity coupled to the nonlinear logarithmic and exponential electrodynamics. It has no horizon and curvature except one conical singularity at $r=0$ with a deficit angle $\delta\phi$. Also we found the counterterm which removes non-logarithmic divergences for the static quintic quasitopological gravity. Using this counterterm one can calculate a finite action and conserved quantities for the quintic quasitopological gravity.