Gravitational waves from Higgs domain walls

Understand

The effective potential for the Standard Model Higgs field allows two quasi-degenerate vacua; one is our vacuum at the electroweak scale, while the other is at a much higher scale.

• The latter minimum may be at a scale much smaller than the Planck scale, if the potential is lifted by new physics.
• This gives rise to a possibility of domain wall formation after inflation.
• If the high-scale minimum is a local minimum, domain walls are unstable and disappear through violent annihilation processes, producing a significant amount of gravitational waves.