Multiverse

The amount of energy infusing empty space seems too small to explain without a multiverse. But physicists have at least one alternative left to explore.

Physicists are confronting their “nightmare scenario.” What does the absence of new particles suggest about how nature works?

If a theory can’t be tested, is it still science?

Nima Arkani-Hamed is championing a campaign to build the world’s largest particle collider, even as he pursues a new vision of the laws of nature.

Explore the deepest mysteries at the frontier of fundamental physics, and the most promising ideas put forth to solve them.

Three physicists have proposed a new solution to one of the deepest mysteries in particle physics: why the Higgs boson has such a tiny mass.

In his latest book, the Nobel Prize winner Steven Weinberg explores how science made the modern world, and where it might take us from here.

Early in cosmic history, our universe may have bumped into another — a primordial clash that could have left traces in the Big Bang’s afterglow.

Testing the multiverse hypothesis requires measuring whether our universe is statistically typical among the infinite variety of universes. But infinity does a number on statistics.