id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
work_hgq52iwbgvcmnl4fxxvnwjtge4	Vincent Lam	Gravitational and Nongravitational Energy: The Need for Background Structures	2011	11	.pdf	application/pdf	5010	305	51	The aim of this paper is to discuss some aspects of the nature gravitational energy within the general theory of relativity. This is a very general definition of the energy-momentum tensor associated with any given matter fields, whose dynamics is derived from a energy-momentum conservation from the point of view of the space-time that is, by their associated Killing vector fields.4 The existence of a genuine (that is, integral) energy(-mometum) conservation law is then bound Now the integral formulation (6) genuinely means (non-gravitational) energy-mometum conservation (with respect to the intergal curves of the timelike vector field with respect to which integral non-gravitational energy-momentum conservation can be obtained; indeed, a timelike Killing vector field can be dependence of tµν shows that there is indeed no local (unique) gravitational energy-momentum, in the sense that such quantity cannot be in background with respect to which gravitational (and non-gravitational indeed) energy-momentum can be defined and localized.	./cache/work_hgq52iwbgvcmnl4fxxvnwjtge4.pdf	./txt/work_hgq52iwbgvcmnl4fxxvnwjtge4.txt