1977, Physicist Frank Wilczek I took a walk that would change the course of particle physics forever. “During that walk, he had two really good ideas,” he recalls. The first was how a theoretical particle, later called the Higgs boson, interacted with other particles. This is how the Higgs boson was discovered decades later. However, the second idea took a little longer to catch on.
Wilczek envisioned a way to make particles that were extremely light, essentially massless. He consulted his colleague, the late Steven Weinberg, who had the same idea. Together, they predicted a class of particles that are now called axions.
Weinberg was optimistic and convinced Wilczek, now at the Massachusetts Institute of Technology, that axions would be easy to find. However, nearly half a century later, we are still searching. In the intervening years, interest in axions grew primarily because of their potential to be elusive dark matter, which makes up 85 percent of the matter in the universe, but waned in favor of other explanations. did.
Today, axions are making a comeback as we fail to track down dark matter and make numerous theoretical and experimental breakthroughs. “Fashion is all the way back,” Wilczek says.
And now we have much more than just the mysterious properties of dark matter. That’s because axions offer a solution to an entire cosmological puzzle, including the elusive dark energy that is thought to cause the universe’s expansion. In short, they are the particles that can solve the universe.