New research by Professor Enrique Gaztanaga of the University of Portsmouth and the Institute of Space Sciences in Barcelona proposes a groundbreaking theory that some black holes might have formed before the Big Bang and survived a cosmic ‘bounce’. This intriguing idea could shed light on dark matter, the gravitational wave background, and the formative years of supermassive black holes and galaxies.
Gaztanaga proposes a new dark matter mechanism involving relic black holes stemming from a pre-big-bounce collapse.
“For almost a century, cosmologists have traced the universe’s history back to a singular event known as the Big Bang,” Professor Gaztanaga remarked.
“The conventional theory suggests that space and time originated from an extremely hot and dense state approximately 13.8 billion years ago, leading to billions of years of cosmic expansion and galaxy formation.”
“This prevailing model has been remarkably successful, accounting for the cosmic microwave background (CMB) radiation—an echo from the early universe—and accurately predicting the distribution of galaxies across the cosmos.”
“Nevertheless, several profound mysteries in physics remain unresolved. We still lack understanding about the Big Bang’s cause, the universe’s initial special conditions, the rapid expansion known as inflation, and the nature of dark matter, which outnumbers ordinary matter by a factor of five.”
“Our research investigates the possibility that the universe didn’t originate from a single shock but may have emerged from a cosmic bounce that mimicked inflation, with some of the universe’s oldest objects potentially surviving as relics from an earlier epoch.”
Some black holes may have emerged during the universe’s early stages and survived this cosmic bounce, leaving behind relics that could still influence galaxy structures billions of years later.
Others may have formed immediately after density fluctuations were amplified, resulting in a more uneven distribution of matter during the early universe.
These concentrated clumps of matter collapse more readily under their own gravity, increasing the likelihood of forming large cosmic structures and black holes early on.
Within Einstein’s theory of general relativity, the Big Bang represents a singularity, a point where density becomes infinite and known physical laws cease to function.
Many physicists view this as indicative of an incomplete understanding of the universe’s earliest moments.
Another concept to consider is bounce cosmology. This theory posits that our universe originated from a colossal cloud that first contracted and then expanded.
Rather than collapsing into an infinite singularity, the universe reaches a very high but finite density before reversing its motion.
“Singularities often signal that a theoretical framework has hit its limitations,” Professor Gaztanaga asserts.
“Bounces offer an avenue for the universe to transition from contraction to expansion without necessitating new and exotic physics.”
Scientists posit that this bounce might emerge naturally from quantum physics. Under extreme densities, quantum effects generate powerful pressures that prevent matter from compressing infinitely. This phenomenon stabilizes dense objects like white dwarfs and neutron stars, potentially replicating the inflationary phase.
New models suggest that similar effects could manifest on a cosmic scale. As the universe contracts, this quantum pressure can halt the collapse and trigger a rebound into expansion.
This cosmic bounce could address two pressing mysteries in cosmology.
First, it could elucidate why the early universe expanded so rapidly and uniformly in all directions.
Second, it may help explain why the universe appears to be expanding at an accelerating rate today—an effect currently attributed to a poorly understood force referred to as dark energy.
A notable hypothesis is that certain structures formed during the collapse phase may have persisted after the bounce.
New calculations indicate that compact objects exceeding about 90 meters in size might traverse the transition and reemerge as remnants in the expanding universe.
Potential artifacts include gravitational waves, density fluctuations, and ancient black holes.
These relic black holes could serve to explain dark matter, the unseen material that shapes large-scale structures of galaxies and the universe.
If substantial numbers were created during the bounce, they could constitute a significant portion, or even all, of dark matter.
This notion may also provide insight into the recent observations by the NASA/ESA/CSA James Webb Space Telescope of an unexpectedly massive object, often referred to as a ‘tiny red dot,’ in the early universe.
Many astronomers speculate these sources are related to rapidly growing black holes that emerged shortly after the Big Bang.
“If a supermassive black hole existed right after the bounce, we wouldn’t have to start from square one when forming the initial galaxies in the early universe,” Gaztanaga explained.
This theory also presents predictions that could be tested through future observations.
Scientists may seek to detect relic gravitational waves from previous cosmic stages or subtle patterns in the CMB that preserve traces of a pre-Big Bang universe.
“Much research is still required to validate these concepts,” Professor Gaztanaga states.
“However, if the universe did experience a bounce, the dark structures that shape today’s galaxies might be remnants from an earlier cosmic age that preceded the Big Bang.”
This paper is published in Physical Review D.
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Enrique Gaztanaga. 2026. Cosmological Bounce Relics: Black Holes, Gravitational Waves, and Dark Matter. Physics. Rev.D 113, 043544; doi: 10.1103/pr4p-6m49
Source: www.sci.news
