English

Baryogenesis and Gravitational Waves from Runaway Bubble Collisions

High Energy Physics - Phenomenology 2016-11-15 v3 Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology

Abstract

We propose a novel mechanism for production of baryonic asymmetry in the early Universe. The mechanism takes advantage of the strong first order phase transition that produces runaway bubbles in the hidden sector that propagate almost without friction with ultra-relativistic velocities. Collisions of such bubbles can non-thermally produce heavy particles that further decay out-of-equilibrium into the SM and produce the observed baryonic asymmetry. This process can proceed at the very low temperatures, providing a new mechanism of post-sphaleron baryogenesis. In this paper we present a fully calculable model which produces the baryonic asymmetry along these lines as well as evades all the existing cosmological constraints. We emphasize that the Gravitational Waves signal from the first order phase transition is completely generic and can potentially be detected by the future eLISA interferometer. We also discuss other potential signals, which are more model dependent, and point out the unresolved theoretical questions related to our proposal.

Keywords

Cite

@article{arxiv.1608.00583,
  title  = {Baryogenesis and Gravitational Waves from Runaway Bubble Collisions},
  author = {Andrey Katz and Antonio Riotto},
  journal= {arXiv preprint arXiv:1608.00583},
  year   = {2016}
}

Comments

30 pages, 8 figures. v2: typos fixed and references added v3: discussion regarding the lifetime of the dark Z's fixed and the discussion on their relic abundance is removed, minor corrections, and references added. Conclusions are intact. Accepted to JCAP

R2 v1 2026-06-22T15:09:29.806Z