For almost a century, cosmologists have traced everything back to one single starting point. New research out of the University of Portsmouth suggests that starting point might not be the whole story, and that some black holes drifting through space today could be genuine leftovers from before the Big Bang.
A Universe That Bounced Instead of Exploded
The standard picture of cosmic history is well established: space and time emerged from an extremely hot, dense state roughly 13.8 billion years ago, and the universe has been expanding ever since. It’s a model that explains the cosmic microwave background and correctly predicts how galaxies are scattered across the sky. But it comes with an uncomfortable feature baked in, run the equations of general relativity backward far enough, and you hit a singularity, a point of infinite density where the laws of physics simply stop making sense.
Professor Enrique Gaztañaga, an astrophysicist at Portsmouth’s Institute of Cosmology and Gravitation, proposes an alternative. Instead of beginning at an impossible infinite point, the universe might have started as a vast cloud that contracted under its own gravity, reached an extremely high but still finite density, and then bounced, reversing direction into the expansion we observe today. “Singularities often signal that our theoretical description has reached its limits,” Gaztañaga said.
Fossils From Before the Beginning
Here’s where it gets genuinely strange. In the moments before a bounce like this, unusually large density fluctuations could have collapsed into black holes, real physical objects that then survived the bounce itself and carried straight through into our expanding universe. These wouldn’t be ordinary black holes formed from dying stars, they’d predate every star, galaxy, and the Big Bang as we currently define it, effectively fossils from a universe that came before ours.
If enough of these relic black holes formed during the bounce, Gaztañaga’s model suggests they could account for a substantial fraction, potentially even all, of dark matter, the invisible material that outweighs ordinary matter roughly five to one and shapes how galaxies hold together. It’s a genuinely different answer than most dark matter searches have pursued, decades of experiments have hunted for exotic new particles, largely without success, while this idea reaches for something already known to exist: black holes, just impossibly old ones.
An Answer to Webb’s “Little Red Dots” Too
The model doesn’t stop at dark matter. It may also help explain one of the more stubborn puzzles to come out of the James Webb Space Telescope, unexpectedly massive, extremely early objects nicknamed “little red dots,” widely suspected to be supermassive black holes that somehow grew far too large, far too quickly after the Big Bang. “If massive black holes already existed immediately after the bounce, the early universe would not need to start from scratch when building the first galaxies,” Gaztañaga explained.
Testable, Not Just Theoretical
Unlike a lot of pre-Big Bang speculation, this idea comes with concrete predictions attached. Researchers could search for relic gravitational waves generated during that earlier collapsing phase, or look for subtle, specific patterns hidden within the cosmic microwave background itself, signatures that a purely standard Big Bang origin wouldn’t produce. The study, published in Physical Review D, doesn’t claim to have solved dark matter, but it does offer a genuinely different, testable direction for a problem that’s resisted every other approach for decades.
For more on the research, check out the full release from the University of Portsmouth and the published study in Physical Review D.