Stephen Hawking says the Higgs boson, the so-called "God particle," has the potential to destroy the universe. Should you worry? Probably not, experts say.
In a new book, the celebrated physicist suggests that at very high energy levels the boson might become unstable, resulting in a "catastrophic vacuum decay" that would completely collapse space and time.
He's not the first scientist to mull a doomsday brought on by the Higgs boson, a suggestion that quantum fluctuations might create a "bubble" of vacuum that could expand across space and destroy the universe.
But it's not likely to happen anytime in the foreseeable future, scientists say.
"Most likely it will take 10 to the 100 years [a 1 followed by 100 zeroes] for this to happen, so probably you shouldn't sell your house and you should continue to pay your taxes," says Joseph Lykken, a theoretical physicist at the Fermi National Accelerator Laboratory in Batavia, Illinois.
The 2012 discovery of the Higgs boson is the lynchpin of the Standard Model of physics, signaling the existence of a Higgs field, invisible but present everywhere in the universe and giving all other particles their mass.
In the doomsday scenario put forward by Hawking and others, the Higgs field -- created at the instant of the universe's birth and creating its own energy source since then -- may be fluctuating between two states.
"Just like matter can exist as liquid or solid, so the Higgs field, the substance that fills all space-time, could exist in two states," Gian Giudice, a theoretical physicist at the CERN, where the Higgs boson was finally detected, has said.
Hawking lays out the scenario of a Higgs cataclysm in his book.
"The Higgs potential has the worrisome feature that it might become metastable at energies above 100 gigaelectronvolts (GeV)," he writes. "This could mean that the universe could undergo catastrophic vacuum decay, with a bubble of the true vacuum expanding at the speed of light. This could happen at any time and we wouldn't see it coming."
Such an expanding bubble could swallow atoms, break down atomic nuclei, resulting in conditions where hydrogen could be the only element capable of existing in the universe, Giudice has said.
However, even Hawking doesn't believe we face the prospect of the end of everything any time soon, even if we wanted to test the hypothesis ourselves.
"A particle accelerator that reaches 100bn GeV would be larger than Earth," Hawking writes, "and is unlikely to be funded in the present economic climate."
