Idea on the edgeSpeculative · Universe

Vacuum decay

The vacuum may not be the lowest energy state. If a bubble of a more stable vacuum forms, it could expand and rewrite the laws of physics inside.

Speculative · not yet proven

Idea: The vacuum is metastable, not truly stable
Trigger: Quantum tunnelling to a lower energy state
Consequence: A bubble expanding at near light speed
Evidence: The Higgs mass sits near the stability edge

A bubble in the false vacuum

Stannered / Wikimedia Commons, CC BY 2.5

A false vacuum

The Higgs field may rest in a local minimum rather than the true lowest state. If so, our vacuum is metastable: it looks stable, but a lower energy state exists. Measurements of the Higgs and top quark masses put us close to the boundary between the two.

The bubble

Quantum tunnelling could create a small region in the lower state. The boundary of that region would expand at close to light speed, converting space to the new vacuum as it grows. Inside, particle physics would work differently.

How likely

Calculations suggest the expected time for such an event is enormously long, far beyond the current age of the universe. The idea is a real prediction of quantum field theory, not a near-term threat.

Key publications

Year	Paper	Venue	Link
1977	Coleman, Fate of the false vacuum: Semiclassical theory	PRD 15, 2929	DOI
1977	Callan & Coleman, Fate of the false vacuum. II. First quantum corrections	PRD 16, 1762	DOI
1980	Coleman & De Luccia, Gravitational effects on and of vacuum decay	PRD 21, 3305	DOI

Selected papers for further reading. DOI links open the publisher's record; preprints are linked on arXiv.

Worth knowing

Inside the bubble, particle physics could work differently.
The boundary would expand at close to light speed.
If it ever happens, we would not see it coming.