Well-defined equations of motion without constraint of external sources

Autor:	Croker, Kevin S., Weiner, Joel L., Farrah, Duncan
Rok vydání:	2022
Předmět:	General Relativity and Quantum Cosmology Astrophysics - Cosmology and Nongalactic Astrophysics
Druh dokumentu:	Working Paper
DOI:	10.1103/PhysRevD.105.084042
Popis:	We present a new approach to constrained classical fields that enables the action formalism to dictate how external sources must enter the resulting equations of motion. If symmetries asserted upon the varied fields can be modeled as restrictions in Fourier space, we prove that these restrictions are automatically applied to external sources in an unambiguous way. In contrast, the typical procedure inserts symmetric ansatze into the Euler-Lagrange differential equations, even for external sources not being solved. This requires ad hoc constraint of external sources, which can introduce leading-order errors to model systems despite superficial consistency between model field and source terms. To demonstrate, we consider Robertson-Walker cosmologies within General Relativity and prove that the influence of point-like relativistic pressure sources on cosmological dynamics cannot be excluded by theoretical arguments. Comment: 3 pages, accepted at PRD
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2203.13826 Zobrazit plný text záznamu View this record from Arxiv