Juan Garcia-Bellido

Dynamics of Symmetry Breaking and Tachyonic Preheating

We reconsider the old problem of the dynamics of spontaneous symmetry breaking (SSB) using 3D lattice simulations. We develop a theory of tachyonic preheating, which occurs due to the spinodal instability of the scalar field. Tachyonic preheating is so efficient that SSB typically completes within a single oscillation as the field rolls towards the minimum of its effective potential. We show that, contrary to previous expectations, preheating in hybrid inflation is typically tachyonic. Our results may also be relevant for the theory of the formation of topological defects and of disoriented chiral condensates in heavy ion collisions.

Gauge-invariant inflaton in the minimal supersymmetric standard model

We argue that all the necessary ingredients for successful inflation are present in the flat directions of the Minimally Supersymmetric Standard Model. We show that out of many gauge invariant combinations of squarks, sleptons and Higgses, there are two directions,

Inflationary scenarios from branes at angles

{\bf LLe}

Transforming gravity: from derivative couplings to matter to second-order scalar-tensor theories beyond the Horndeski Lagrangian

, and

Density perturbations and black hole formation in hybrid inflation

{\bf udd}

Confronting Lemaitre–Tolman–Bondi models with observational cosmology

, which are promising candidates for the inflaton. The model predicts more than

Metric perturbations in two field inflation

10^3

MEASURING BARYON ACOUSTIC OSCILLATIONS ALONG THE LINE OF SIGHT WITH PHOTOMETRIC REDSHIFTS: THE PAU SURVEY

e-foldings with an inflationary scale of

Stochastic background of gravitational waves from hybrid preheating

H_{\rm inf}\sim {\cal O}(1-10)

Gravitational wave background from reheating after hybrid inflation

GeV, provides a tilted spectrum with an amplitude of