https://doi.org/10.1140/epjc/s10052-020-8207-0
Regular Article - Theoretical Physics
Mechanics of isolated horizons in scalar-tensor theories
1
Department of Physics, Beijing Normal University, Beijing, 100875, China
2
Institute for Gravitation and the Cosmos & Physics Department, Pennsylvania State University, University Park, PA, 16802, USA
* e-mail: mayg@bnu.edu.cn
Received:
28
April
2020
Accepted:
4
July
2020
Published online:
15
July
2020
Based on the first-order action for scalar-tensor theories with the Immirzi parameter, the symplectic form for the spacetimes admitting a weakly isolated horizon as internal boundary is derived by the covariant phase space approach. The first law of thermodynamics for the weakly isolated horizons with rotational symmetry is obtained. It turns out that the Immirzi parameter appears in the expression of the angular momentum of isolated horizon, and the scalar field contributes to the horizon entropy.
© The Author(s), 2020