It's an idea that's out there: The universe as we know it might just all of a sudden destabilize and tumble into an entirely new sort of physical reality. The forces that make our worlds what they are would be gone, and so too would particles and reactions and masses and light itself. Some new stuff would take its place, but that wouldn't matter very much to us because we would be gone in the deepest, truest sense imaginable. Not even star stuff.
Conspiracy theorist-types are fans of this idea—or a ghastly mangling of it, rather—and maybe some internet garbage about the Higgs boson destroying the universe has come across your radar. This is what said types are referring to (however incorrectly) and it's not entirely just pulled from someone's ass.
It may, however, prove to be even more unlikely than (some) physicists had previously thought. This argument is outlined in a recent study in the Physical Review Letters, courtesy of Russian physicist Andrey Pikelner and his team, and an accompanying American Physical Society Viewpoint: The vacuum might be stable after all, and not just "metastable." The very settled-looking universe around us and all of its forces and particles might truly chill forever.
The universe is a vacuum filled by the Higgs field. You can just look at it is some energy that hangs out everywhere and when particles interact with it, they wind up with mass. This energy has a value or potential, but it might not be the only possible value.
It might be a local minimum, or a false vacuum, and some big event might come along one day and knock us out of that local minimum. The universe would then settle at a new minimum, either another local minimum (metastable) or the one true minimum (stable).
"If the Universe lies in the only (or deepest) minimum of the potential, then its future is not threatened," Alexander Kusenko, a physicist at the University of California, Los Angeles, writes. "However, it is also possible that the current minimum is "local" and a deeper minimum exists, or the potential has a bottomless abyss separated from the local minimum by a finite barrier. In these cases, the Universe will eventually tunnel out into some other state, in which life as we know it might be impossible. Of course, the probability of such a catastrophic event must be small, because the Universe has remained in its present state for over ten billion years."
The Higgs boson discovery confirmed that the ground energy state of the universe depends on the potential of the Higgs field. As Kusenko explains, we should be able to calculate whether or not we're in a true ground state or just a stopping-off point based on the masses of the Higgs boson and the top quark. The current mass estimates of the Higgs boson, around 125 giga-electron-volts, imply that things could go either way.
The Pikelner study calculates the Higgs potential with what Kusenko assures us is the most reliable analysis to date. Basically, if current values for the Higgs boson and other Standard Model particles are mostly correct, absolute stability is possible. This depends on those values not changing and that some emerging New Physics doesn't screw everything up, which it probably will. But, even if the universe is metastable, we shouldn't expect things to go haywire for many billions of years, so rest easy-ish.