Exactly 50 years ago, when I was a PhD student, I wrote an article for this magazine about growing evidence of black holes, regions of space where gravity is so strong that light can never escape. . Today there is no doubt about their existence. They form from collapsing stars, and supermassive ones are found in the centers of galaxies. One of them even took a picture of the two of them. But my article also mentioned a more speculative possibility. A small black hole may have formed in the early universe, right after the Big Bang.
I was working on this idea under the supervision of Stephen Hawking, who started thinking about such possibilities only a few years ago. Our collaboration set the trajectory of my career. . Many of them have been devoted to studying what we now call primordial black holes. We don’t yet know if they formed, but there’s good reason to think they might have. could be the answer to a whole range of cosmological conundrums.
But recently, I’ve become interested in even more exotic possibilities. Some black holes may be older than the universe itself. This is a wild idea, but not unthinkable. And new research suggests that one day we may be able to clearly identify them. This is a breakthrough that fundamentally changes our understanding of cosmology.
Most cosmologists believe that all matter and energy that permeates our universe today is …
