Constraint on ghost-free bigravity from gravitational Cherenkov radiation

• 田中, 貴浩

• Tanaka, Takahiro

• Yamamoto, Kazuhiro

• Yamashita, Yasuho

抄録

We investigate gravitational Cherenkov radiation in a healthy branch of background solutions in the ghost-free bigravity model. In this model, because of the modification of dispersion relations, each polarization mode can possess subluminal phase velocities, and the gravitational Cherenkov radiation could be potentially emitted from a relativistic particle. In the present paper, we derive conditions for the process of the gravitational Cherenkov radiation to occur and estimate the energy emission rate for each polarization mode. We found that the gravitational Cherenkov radiation emitted even from an ultrahigh energy cosmic ray is sufficiently suppressed for the graviton's effective mass less than 100 eV, and the bigravity model with dark matter coupled to the hidden metric is therefore consistent with observations of high energy cosmic rays.

収録刊行物

• Physical Review D - Particles, Fields, Gravitation, and Cosmology

  Physical Review D - Particles, Fields, Gravitation, and Cosmology 94 (6), 2016-09-21

  American Physical Society

詳細情報

• CRID: 1050282810817772032
• NII論文ID: 120005973371
• ISSN: 15502368
• HANDLE: 2433/218350
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
  • IRDB
  • CiNii Articles