All articles tagged with #primordial black holes
Researchers propose a bouncing cosmology in which some black holes formed during a prior contracting phase survive the bounce as relics, potentially comprising all or part of dark matter and seeding early galaxy formation; the idea links the bounce to inflation and dark energy and suggests tests via relic gravitational waves or subtle pre–Big Bang patterns in the cosmic microwave background.
Goethe University and TU Wien physicists propose that if spacetime can crystallize into a regular four‑dimensional lattice, a tiny energy perturbation could trigger a critical collapse that births microscopic black holes. Their work provides simple, exact solutions to Einstein’s equations for this process and suggests a possible primordial-black-hole pathway, but it does not prove such holes exist and notes they would evaporate quickly via Hawking radiation.
New research models how a star capturing a primordial black hole (PBH) would evolve, finding that capture is most likely in three-body systems and leads to two possible fates: a rapid, disk-driven explosion (a Hawking-star) that destroys the star, or a slower, quasi-steady consumption that leaves a massive, high-spin remnant. The explosive path would produce multimodal electromagnetic signals (X-ray flash, UV/blue transient, possibly a low-luminosity GRB) while the quiet path could emit gravitational waves in the future. Observing these outcomes could constrain how much PBHs contribute to dark matter.
New JWST observations of Abell2744-QSO1 show a massive black hole dominating a nearly metal-free, star-poor object just 700 million years after the Big Bang, implying the black hole may have formed before its host galaxy via direct-collapse or primordial pathways and prompting a rethink of how black holes and galaxies grow together.
Astronomers analyzing a 2019 microlensing flare of a star in the Large Magellanic Cloud say the signal is best explained by a moon-mass primordial black hole—Phoebe—likely in the Milky Way's dark matter halo about 60,000 light-years away. While a rogue exoplanet could cause similar lensing, the PBH explanation is favored and, if confirmed, would illuminate dark matter and early-universe physics and spur high-cadence microlensing surveys with the Roman and Vera Rubin observatories. Some related analyses (e.g., Andromeda PBH candidates) have contested the PBH interpretation, so confirmation will require more sensitive observations.
An hour-long gravitational microlensing event in the Large Magellanic Cloud, dubbed Phoebe, is likely caused by a lunar-mass object in the Milky Way halo—potentially a primordial black hole and a rare window into ancient dark matter.
Researchers present a new analytic formula describing how spacetime crystals formed during critical collapse could evolve into black holes, providing a precise theoretical framework that could inform studies of primordial black holes—though empirical confirmation remains needed.
A new study proposes that dark matter could be relic primordial black holes surviving a prior cosmic collapse in a Big Bounce, meaning dark structures in galaxies might be remnants from a previous universe. These relic black holes (and associated gravitational waves and density fluctuations) could constitute a significant fraction of dark matter, though the idea must be tested against data from gravitational waves, galaxy surveys, and the cosmic microwave background.
A new cosmological model argues dark matter could be a population of pre-existing black holes that survived a prior universe’s collapse and rebound in a cyclic cosmos. If cosmic bounces allow relic structures to endure, the current universe could be born with these black holes rather than needing exotic particles, potentially solving both the dark-matter question and black-hole origins—but the idea must be tested against data from gravitational waves, galaxy surveys, and the cosmic microwave background.
Researchers analyzing a LIGO-detected gravitational-wave signal propose it may come from a primordial black hole with subsolar mass, offering a potential direct test of PBH existence and a possible link to dark matter, though more detections are required for confirmation.
A LIGO detection involving an object lighter than a solar mass challenges standard stellar-black-hole formation, with researchers proposing a primordial black hole created in the early universe as the explanation. If confirmed, PBHs could account for dark matter, but further detections and next‑gen observatories like LISA and Cosmic Explorer are needed to build stronger evidence.
In 1974 Stephen Hawking published a short Nature paper proposing that tiny primordial black holes, formed in the early universe, could evaporate and explode via Hawking radiation, flipping the view that black holes only grow. The idea, which connects quantum mechanics to gravity, later sparked the black hole information paradox as it suggested information might be lost; Hawking and collaborators’ later work proposed mechanisms for information escape, including wormholes, though direct evidence remains elusive. Ongoing research, including gravitational waves and James Webb observations, continues to investigate primordial black holes and their potential cosmological signatures.
KM3NeT detected a 100 PeV neutrino (KM3-230213A) with no known source. A Physical Review Letters study proposes exploding quasi-extremal primordial black holes with a dark charge as a possible origin, invoking Hawking radiation that heavier, lighter PBHs would emit high-energy particles in a final burst. IceCube has not observed a comparable event, possibly due to its different energy window. If correct, such PBH evaporations could occur roughly every decade, linking ultra-high-energy neutrinos to PBH physics.
A rare, ultrahigh-energy neutrino detected by KM3NeT in 2023 prompts a bold hypothesis: a quasi-extremal primordial black hole dumping dark electrons, triggering a rapid explosion that emits a narrow band of neutrinos; the idea, outlined in a Physical Review Letters preprint and set for formal publication, could explain why KM3NeT saw the event while IceCube did not, but it remains speculative pending more data and analysis.
A 220 PeV neutrino detected by KM3NeT's ARCA detector in February 2023 far exceeds energies from any accelerator and challenges existing models; a University of Massachusetts Amherst team suggests it came from a primordial black hole evaporating via Hawking radiation, offering a potential link to dark matter and a window into new physics beyond the Standard Model.