Acausality in nonlocal gravity theory

Ying-li Zhang, Kazuya Koyama, Misao Sasaki, Gong-Bo Zhao

Research output: Contribution to journalArticlepeer-review

126 Downloads (Pure)

Abstract

We investigate the nonlocal gravity theory by deriving nonlocal equations of motion using the traditional variation principle in a homogeneous background. We focus on a class of models with a linear nonlocal modification term in the action. It is found that the resulting equations of motion contain the advanced Green's function, implying that there is an acausality problem. As a consequence, a divergence arises in the solutions due to contributions from the future infinity unless the Universe will go back to the radiation dominated era or become the Minkowski spacetime in the future. We also discuss the relation between the original nonlocal equations and its biscalar-tensor representation and identify the auxiliary fields with the corresponding original nonlocal terms. Finally, we show that the acusality problem cannot be avoided by any function of nonlocal terms in the action.
Original languageEnglish
Article number39
JournalJournal of High Energy Physics
Volume2016
Issue number3
DOIs
Publication statusPublished - 7 Mar 2016

Keywords

  • hep-th
  • astro-ph.CO
  • gr-qc
  • RCUK
  • STFC
  • ST/K00090/1
  • Classical Theories of Gravity
  • Models of Quantum Gravity

Fingerprint

Dive into the research topics of 'Acausality in nonlocal gravity theory'. Together they form a unique fingerprint.

Cite this