What If the Big Bang Was Actually a Big Bounce?

Steinhardt and company imagine a universe that expands for perhaps a trillion years, driven by the energy of an omnipresent (and hypothetical) field, whose behavior we currently attribute to dark energy. When this energy field eventually grows sparse, the cosmos...

What Goes On in a Proton? Quark Math Still Needs Answers

Objects are made of atoms, and atoms are likewise the sum of their parts—electrons, protons, and neutrons. Dive into one of those protons or neutrons, however, and things get weird. Three particles called quarks ricochet back and forth at nearly the speed of light,...

Why Do Matter Particles Come in Threes?

The universe has cooked up all sorts of bizarre and beautiful forms of matter, from blazing stars to purring cats, out of just three basic ingredients. Electrons and two types of quarks, dubbed “up” and “down,” mix in various ways to produce every atom in existence....