Stochastic Baryogenesis

Yi-Peng Wu (1) , Kalliopi Petraki (1)

1 LPTHE - Laboratoire de Physique Théorique et Hautes Energies

Using a multi-field stochastic approach, we investigate the vacuum expectation value (VEV) during inflation of a scalar field charged under a mildly broken global U(1) symmetry that can play the role of baryon or lepton number, or possibly a dark baryon number or a combination of the three. Even for a CP invariant Lagrangian, the stochastic distribution of inflationary VEVs in general breaks CP spontaneously, allowing for successful baryogenesis via the Affleck-Dine mechanism. For the Hubble scale during inflation H* as high as 1013 GeV, we show that the post-inflationary relaxation of the charged scalar with stochastic initial conditions can explain the observed baryon asymmetry, and that a charged scalar mass at the order of H* is favored by the isocurvature constraints.

Mots clés: mass: scalar; field theory: scalar; baryon: asymmetry; invariance: CP; stochastic; inflation; baryogenesis; Affleck-Dine model; boundary condition; baryon number; lepton number; isocurvature; symmetry: U(1)

Domaines: Physique des Hautes Energies - Phénoménologie [hep-ph]; Astrophysique [astro-ph]

Yi-Peng Wu, Kalliopi Petraki. Stochastic Baryogenesis. JCAP, 2021, 01, pp.022. ⟨10.1088/1475-7516/2021/01/022⟩. ⟨hal-02934066⟩