INVESTIGADORES
ROMERO Gustavo Esteban
artículos
Título:
Relativistic rigid systems and the cosmic expansion
Autor/es:
COMBI, LUCIANO; ROMERO, GUSTAVO E.
Revista:
GENERAL RELATIVITY AND GRAVITATION
Editorial:
SPRINGER/PLENUM PUBLISHERS
Referencias:
Año: 2020 vol. 52
ISSN:
0001-7701
Resumen:
We analyze the necessary conditions for a body to remain rigid in an expanding cosmological Universe. First, we establish the main theorems and definitions for having a rigid body in a general spacetime as well as the new concept of quasilocal rigidity. We apply the obtained results to a homogeneous universe exploring the differences with flat spacetime. We discuss how the concept of rigid body helps to understand the expansion of space in cosmology. Finally, using a rigid system as a reference frame, we calculate the gravitational energy, and we compare it with previous results in the literature.