When an invisible entity making up 85% of the universe’s mass stumps the greatest scientific minds of our time, awe is an understandable response.

Physicists call it dark matter, a substance they describe as the cosmic glue, the scaffolding, a web that uses gravity to corral, shape and hold together stars, planets and galaxies. Yet nobody knows exactly what it is.

Dark matter’s existence is only inferred from its gravitational effects on visible matter. Together with dark energy—a mysterious force causing the universe to expand at an accelerated rate—they are the biggest scientific mysteries of our time.

A new model suggests dark matter may be more complex than a single substance, potentially reshaping how scientists interpret hidden structures across the universe.

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At one-one-thousandth of a second after the Big Bang, the great annihilation event should have wiped out all matter, leaving a universe of only radiation. Why still don’t know why any matter survived. Well, a new finding from the LHC brings us one step closer to understanding why there’s something rather than nothing.

Dr. Caplan Paper for Review:
https://arxiv.org/abs/2312.

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It may well take years to prove, but a pair of University of Miami astrophysicists could be on the verge of a cosmic breakthrough that will confirm the existence of primordial black holes and the role they play in one of cosmology’s greatest mysteries.

Believed to have formed within the first fraction of a second after the Big Bang, primordial black holes are purely theoretical. But if confirmed, these hypothetical cosmic phenomena, which could range from asteroid-sized to massive, could explain a lot, including the nature of dark matter—the invisible substance that constitutes about 85% of all matter in the universe, acting as “gravitational glue” that holds galaxies together.

“We believe our study will aid in confirming that they actually do exist,” Nico Cappelluti, an associate professor in the College of Arts and Sciences’ Department of Physics, said of the research he and Ph.D. student Alberto Magaraggia have conducted.

Astronomers studying a distant superluminous supernova uncovered a strange pattern hidden in its light: a rapidly accelerating “chirp.” For decades, astronomers have used distant supernova explosions as cosmic beacons to study fundamental physics and measure properties of the universe. While exam

Astronomers have an answer for a long-running mystery in astrophysics: why is the growth of supermassive black holes so much lower today than in the past? A study using NASA’s Chandra X-ray Observatory and other X-ray telescopes found that supermassive black holes are unable to consume material as rapidly as they did in the distant past. The results appeared in the December 2025 issue of The Astrophysical Journal.

Ten billion years ago, there was a period that astronomers call “cosmic noon,” when the growth of supermassive black holes (those with millions to billions of times the mass of the sun) was at its peak across the entire history of the universe. Between cosmic noon and now, however, astronomers have seen a major slowdown in how rapidly black holes are growing.

“A longstanding mystery has been the cause of this big slowdown,” said Zhibo Yu of Penn State University, lead author of the new study. “With these X-ray data and supporting observations at other wavelengths, we can test different ideas and narrow down the answer.”