# Gravitational energy Defining energy in relativistic theories is surprisingly subtle. There are different definitions depending on the asymptotic structure of the spacetime, symmetry, etc. ## Refs - a good review: [[Rsc0020 Chapter 19 Conserved charges in AdS by FischettiKellyMarolf]] ## Asymptotically flat - [[0487 ADM mass|ADM energy]]: spatial infinity - [[0594 Bondi-Sachs energy|Bondi-Sachs energy]]: null infinity - [[0269 Brown-York stress tensor|Brown-York energy]] - [[2001#Chrusciel, Herzlich]]: a global invariant (uses the full metric) ## Asymptotically AdS - [[1982#Abbott, Deser]] - [[1995#Hawking, Horowitz]]: background subtraction - [[1999#Balasubramanian, Kraus]]: counter term ## Higher derivative - [[0425 Gauss-Bonnet gravity|GB gravity]]: [[2003#Padilla]] ## See also - [[0595 Quasi-local energy]]