Bubble wall velocity from holography

Cosmological phase transitions proceed via the nucleation of bubbles that subsequently expand and collide. The resulting gravitational wave spectrum depends crucially on the bubble wall velocity. We use holography to compute the wall velocity from first principles in a strongly coupled, non-Abelian, fourdimensional gauge theory. The wall velocity is determined dynamically in terms of the nucleation temperature. We verify that ideal hydrodynamics provides a good description of the system everywhere except near the wall.

Automated summary

Cosmological phase transitions occur via the nucleation, expansion, and collision of bubbles, with the resulting gravitational wave spectrum depending on the bubbles' wall velocity. Using holography, the wall velocity in a strongly coupled, non-Abelian, four-dimensional gauge theory is calculated from first principles. The dynamic determination of the wall velocity in relation to the nucleation temperature is verified, with ideal hydrodynamics providing an accurate description of the system except near the wall.