Science › Creation theories
Vacuum decay and bubbles of new space
1977· Idea
Well supportedStrong evidence or math, but not fully tested.
How a false vacuum ends: a bubble of lower-energy space forms by chance, then expands at nearly the speed of light.
See it on the Science map →How it works
A false vacuum does not decay everywhere at once. A tiny bubble of the lower-energy state appears at a random spot, then grows; its wall soon moves at nearly light speed, carrying the released energy. Inside, particles could have different masses and forces, so ordinary chemistry might be impossible. Because the wall travels almost as fast as light, nothing could warn of its arrival. The chance of a bubble per unit of space and time is fixed, but can be fantastically small.
Why it matters
Bubbles were how Guth's first inflation model tried to stop, they are how eternal inflation makes new universes, and they are how our own vacuum could someday end.
Think of it like
Like supercooled water freezing: one ice crystal forms at a single speck, then the freeze races outward through the whole bottle.
How we know
Coleman's 1977 theory is standard physics. In 2024 a team in Trento, Italy, watched bubbles of a 'true vacuum' form in an ultracold atomic gas, at rates matching theory. No cosmic bubble has been seen.
Still a mystery
Coleman and De Luccia called it 'the ultimate ecological catastrophe' in 1980. Whether one happened in our distant past, or will in our future, is unknown.
Connections (3)
▸False vacuum: energy trapped in empty space can end in Vacuum decay and bubbles of new spaceWell supported
The relationship
A false vacuum is protected by an energy barrier, but not perfectly. Quantum tunneling lets a tiny region slip through to the lower state. Small bubbles collapse back, because their wall costs energy; a bubble above a critical size gains more from its interior than its wall costs, and grows without limit. The decay rate depends exponentially on the barrier's height and width.
How the link was found
Igor Kobzarev, Lev Okun and Mikhail Voloshin in Moscow studied such bubbles in 1974. Sidney Coleman at Harvard gave the standard rate calculation in 1977, with Curtis Callan; Coleman and Frank De Luccia added gravity in 1980.
Is it proven?
The method uses the same tunneling physics that explains radioactive decay, and lab analogs show the predicted bubbles. No decay of a cosmic false vacuum has been observed.
Open questions and mysteries
Because the rate is exponentially sensitive, small uncertainties in inputs change predicted lifetimes by enormous factors. How gravity and expansion alter tunneling is still debated.
▸The Higgs field and boson (2012) may sit in a false vacuum, risking Vacuum decay and bubbles of new spaceWell supported
The relationship
The Higgs field's energy hill is reshaped by quantum effects of the particles it touches, above all the heavy top quark. With the measured Higgs mass, about 125 GeV, the calculated hill turns downward at extreme field strengths, around 10¹⁰ GeV and beyond, revealing a deeper valley. Our vacuum would then be false but extremely long-lived: metastable.
How the link was found
Soon after the 2012 discovery, precise calculations by Giuseppe Degrassi, Alessandro Strumia and colleagues (2012–13) placed our vacuum in the metastable zone, close to the border with stable.
Is it proven?
The inputs are measured: a top quark under 1% lighter would make the vacuum stable. One 2018 estimate puts the lifetime near 10¹⁶¹ years. Cosmic rays outdo colliders, so colliders pose no risk (Hut and Rees, 1983).
Open questions and mysteries
It assumes no unknown particles up to enormous energies; new physics could stabilize it. Why nature sits so near the stable–unstable border, and how our vacuum survived the hot early universe, are open.
▸Vacuum decay and bubbles of new space makes the bubbles of Eternal inflation and bubble universesSpeculative
The relationship
In this version, space sits in a high-energy false vacuum that inflates. Now and then a bubble of lower-energy vacuum forms. With gravity included, a bubble's interior looks, from inside, like an infinite expanding universe. But the false vacuum between bubbles grows faster than bubbles consume it, so new bubbles keep forming forever. Our universe would be the inside of one.
How the link was found
Sidney Coleman and Frank De Luccia (1980) found the universe-like bubble interior; J. Richard Gott (1982) proposed our universe is one. Guth and Erick Weinberg (1983) showed bubbles never fill all space.
Is it proven?
Not proven. The math is consistent, and it predicts our space should be very slightly curved, like a saddle. Measurements find space flat to a fraction of a percent, which neither confirms nor rules this out.
Open questions and mysteries
Whether string theory really allows long-lived, high-energy vacuums is disputed; a 2018 'swampland' conjecture by Cumrun Vafa and colleagues suggests it may not.