# Spacetime mappings of the Brown-York quasilocal energy

## TL;DR

This paper investigates how the Brown-York quasilocal energy behaves under conformal and Kerr-Schild transformations in spherical symmetry, comparing its properties with the Misner-Sharp-Hernandez energy.

## Contribution

It derives the transformation laws of the Brown-York energy under specific spacetime mappings, providing insights into their behavior in spherical symmetry.

## Key findings

- Brown-York energy transformation laws derived
- Comparison with Misner-Sharp-Hernandez energy elucidated
- Insights into quasilocal energy behavior under spacetime mappings

## Abstract

In several areas of theoretical physics it is useful to know how a quasilocal energy transforms under conformal rescalings or generalized Kerr-Schild mappings. We derive the transformation properties of the Brown-York quasilocal energy in spherical symmetry and we contrast them with those of the Misner-Sharp-Hernandez energy.