Live and recent posts from across the Fediverse tagged #primordialblackholes, aggregated by home.social.
Can a black hole split into two in accordance with Einstein’s general relativity?
A theoretical study exami…
#NewsBeep #News #Science #Astronomy #AU #Australia #blackholeentropy #blackholefragmentation #BlackHoles #cosmiccensorship #Cosmology #eventhorizons #Fermi-LAT #GammaRays #generalrelativity #Hawkingradiation #higherdimensions #modifiedgravity #primordialblackholes #research #rotatingblackholes #SpaceNews #theoreticalphysics #UniversityofSouthernDenmark
https://www.newsbeep.com/au/939331/
Dark Matter May Come From Primordial Black Holes Hiding in the Fifth Dimension
An international team of astronomers says the source of elusive dark matter may be even stranger than previously…
#NewsBeep #News #Physics #darkmatter #fifthdimension #hiddendimension #neutrino #primordialblackholes #Science #UK #UnitedKingdom
https://www.newsbeep.com/uk/800821/
https://www.europesays.com/uk/1251137/ Dark Matter May Come From Primordial Black Holes Hiding in the Fifth Dimension #DarkMatter #FifthDimension #HiddenDimension #neutrino #Physics #PrimordialBlackHoles #Science #UK #UnitedKingdom
Five-dimensional black holes offer a possible explanation for dark matter and neutrinos
A theoretical study…
#NewsBeep #News #Physics #Astronomy #AU #Australia #CosmicStrings #Cosmology #darkdimension #darkmatter #extradimensions #Hawkingradiation #KM3-230213A #KM3NeT #LehmanCollege #MaxPlanckInstituteforPhysics #Phasetransitions #POEMMA-BalloonwithRadio #primordialblackholes #PrincetonUniversity #QuantumGravity #research #Science #SpaceNews #sterileneutrinos
https://www.newsbeep.com/au/923617/
Five-dimensional black holes offer a possible explanation for dark matter and neutrinos
A theoretical s…
#NewsBeep #News #Physics #astronomy #CosmicStrings #Cosmology #darkdimension #darkmatter #extradimensions #Hawkingradiation #KM3-230213A #KM3NeT #LehmanCollege #MaxPlanckInstituteforPhysics #Phasetransitions #POEMMA-BalloonwithRadio #primordialblackholes #PrincetonUniversity #QuantumGravity #research #Science #SpaceNews #sterileneutrinos #UK #UnitedKingdom
https://www.newsbeep.com/uk/798589/
https://www.europesays.com/ie/729490/ Five-dimensional black holes offer a possible explanation for dark matter and neutrinos #Astronomy #CosmicStrings #cosmology #DarkDimension #DarkMatter #Éire #ExtraDimensions #HawkingRadiation #IE #Ireland #KM3230213A #KM3NeT #LehmanCollege #MaxPlanckInstituteForPhysics #PhaseTransitions #Physics #POEMMABalloonWithRadio #PrimordialBlackHoles #PrincetonUniversity #QuantumGravity #Research #Science #SpaceNews #SterileNeutrinos
https://www.europesays.com/uk/1247688/ Five-dimensional black holes offer a possible explanation for dark matter and neutrinos #Astronomy #CosmicStrings #Cosmology #DarkDimension #DarkMatter #ExtraDimensions #HawkingRadiation #KM3230213A #KM3NeT #LehmanCollege #MaxPlanckInstituteForPhysics #PhaseTransitions #Physics #POEMMABalloonWithRadio #PrimordialBlackHoles #PrincetonUniversity #QuantumGravity #Research #Science #SpaceNews #SterileNeutrinos #UK #UnitedKingdom
LIGO Detects Possible Primordial Black Hole Linked to Dark Matter
📰 Original title: A strange LIGO signal could reveal the missing link behind dark matter
🤖 IA: It's clickbait ⚠️
👥 Users: It's clickbait ⚠️
View full AI summary https://en.killbait.com/ligo-detects-possible-primordial-black-hole-linked-to-dark-matter.html?utm_source=mastodon_world&utm_medium=social&utm_campaign=killbait.mastodon_world
LIGO Detects Possible Primordial Black Hole Linked to Dark Matter
📰 Original title: A strange LIGO signal could reveal the missing link behind dark matter
🤖 IA: It's clickbait ⚠️
👥 Users: It's clickbait ⚠️
View full AI summary https://en.killbait.com/ligo-detects-possible-primordial-black-hole-linked-to-dark-matter.html?utm_source=mastodon_social&utm_medium=social&utm_campaign=killbait.mastodon_social
Limits on #PrimordialBlackHoles from the extragalactic gamma-ray background; current status and future projections: https://arxiv.org/abs/2606.10013 -> Are Asteroid-Mass Black Holes Hiding in the Cosmic Gamma-Ray Glow? https://www.universetoday.com/articles/are-asteroid-mass-black-holes-hiding-in-the-cosmic-gamma-ray-glow
Something Revealed Itself by Bending the Light of a Distant Star in 2019—Now Astronomers Are Racing to Find Out What It Was
For just an hour in late 2019, a cosmic mystery revealed itself to astronomers in an unprecedented way:…
#NewsBeep #News #Physics #Astronomy #AU #Australia #bendingthelight #GravitationalMicrolensing #largemagellaniccloud #primordialblackholes #Science #star
https://www.newsbeep.com/au/704254/
Something Revealed Itself by Bending the Light of a Distant Star in 2019—Now Astronomers Are Racing to Find Out What It Was
For just an hour in late 2019, a cosmic mystery revealed itself to astronomers in an unprecedented way:…
#NewsBeep #News #Physics #astronomy #bendingthelight #gravitationalmicrolensing #LargeMagellanicCloud #primordialblackholes #Science #star #UK #UnitedKingdom
https://www.newsbeep.com/uk/611866/
Something Revealed Itself by Bending the Light of a Distant Star in 2019—Now Astronomers Are Racing to Find Out What It Was
For just an hour in late 2019, a cosmic mystery revealed itself to astronomers in an unprecedented way:…
#NewsBeep #News #Physics #Astronomy #bendingthelight #CA #Canada #gravitationalmicrolensing #largemagellaniccloud #primordialblackholes #Science #star
https://www.newsbeep.com/ca/702985/
https://www.europesays.com/uk/993458/ Something Revealed Itself by Bending the Light of a Distant Star in 2019—Now Astronomers Are Racing to Find Out What It Was #Astronomy #BendingTheLight #GravitationalMicrolensing #LargeMagellanicCloud #Physics #PrimordialBlackHoles #Science #Star #UK #UnitedKingdom
https://www.europesays.com/ie/509597/ Something Revealed Itself by Bending the Light of a Distant Star in 2019—Now Astronomers Are Racing to Find Out What It Was #Astronomy #BendingTheLight #Éire #GravitationalMicrolensing #IE #Ireland #LargeMagellanicCloud #Physics #PrimordialBlackHoles #Science #star
Scientists Reveal a Bizarre Space-Time Structural Phenomenon That Could Be Creating Baby Black Holes
The space-time oddities of modern physics may have just been taken to a new level of odd, as…
#NewsBeep #News #US #USA #UnitedStates #UnitedStatesOfAmerica #Physics #blackhole #physicalstructure #primordialblackholes #Science #Space #spacetimecrystal #time
https://www.newsbeep.com/us/664964/
https://www.europesays.com/uk/984774/ Scientists Reveal a Bizarre Space-Time Structural Phenomenon That Could Be Creating Baby Black Holes #BlackHole #PhysicalStructure #Physics #PrimordialBlackHoles #Science #Space #SpacetimeCrystal #time #UK #UnitedKingdom
https://www.europesays.com/ie/502456/ Scientists Reveal a Bizarre Space-Time Structural Phenomenon That Could Be Creating Baby Black Holes #BlackHole #Éire #IE #Ireland #PhysicalStructure #Physics #PrimordialBlackHoles #Science #Space #SpacetimeCrystal #time
Tiny black holes may form out of a crystal-like state in spacetime
Microscopic black holes have long hovered at the edge of theory, forming only in exquisitely balanced states. Now…
#NewsBeep #News #Science #Astronomy #AU #Australia #blackholeformation #Choptuikcollapse #Cosmology #criticalcollapse #Einsteingravity #generalrelativity #large-Dexpansion #microscopicblackholes #primordialblackholes #research #SpaceNews #spacetimecrystal #theoreticalphysics
https://www.newsbeep.com/au/689472/
Massive black hole from the early universe has astronomers looking back to the Big Bang
Far back in cosmic time, one small red object is refusing to behave. Abell 2744–QSO1 app…
#NewsBeep #News #US #USA #UnitedStates #UnitedStatesOfAmerica #Space #Abell2744-QSO1 #Astronomy #BoyuanLiu #Cosmology #earlyuniverse #GalaxyFormation #JamesWebbSpaceTelescope #LittleRedDots #metal-poorgalaxies #primordialblackholes #Research #Science #SpaceNews #supermassiveblackholes
https://www.newsbeep.com/us/635713/
Massive black hole from the early universe has astronomers looking back to the Big Bang
Far back in cosmic time, one small red object is refusing to behave. Abell 2744–QSO1 appears just 700…
#NewsBeep #News #Space #Abell2744-QSO1 #astronomy #BoyuanLiu #Cosmology #EarlyUniverse #GalaxyFormation #jameswebbspacetelescope #littlereddots #metal-poorgalaxies #primordialblackholes #research #Science #SpaceNews #supermassiveblackholes #UK #UnitedKingdom
https://www.newsbeep.com/uk/577310/
Massive black hole from the early universe has astronomers looking back to the Big Bang
Far back in cosmic time, one small red object is refusing to behave. Abell 2744–QSO1 appears just 700…
#NewsBeep #News #Space #Abell2744-QSO1 #Astronomy #BoyuanLiu #CA #Canada #Cosmology #earlyuniverse #GalaxyFormation #Jameswebbspacetelescope #littlereddots #metal-poorgalaxies #primordialblackholes #research #Science #SpaceNews #supermassiveblackholes
https://www.newsbeep.com/ca/661224/
https://www.europesays.com/uk/951378/ Massive black hole from the early universe has astronomers looking back to the Big Bang #Abell2744QSO1 #Astronomy #BoyuanLiu #Cosmology #EarlyUniverse #GalaxyFormation #JamesWebbSpaceTelescope #LittleRedDots #MetalPoorGalaxies #Physics #PrimordialBlackHoles #Research #Science #SpaceNews #SupermassiveBlackHoles #UK #UnitedKingdom
https://www.europesays.com/ie/477713/ Massive black hole from the early universe has astronomers looking back to the Big Bang #Abell2744QSO1 #Astronomy #BoyuanLiu #cosmology #EarlyUniverse #Éire #GalaxyFormation #IE #Ireland #JamesWebbSpaceTelescope #LittleRedDots #MetalPoorGalaxies #PrimordialBlackHoles #Research #Science #SpaceNews #SupermassiveBlackHoles
https://www.europesays.com/ie/455819/ Physicist Proposes Dark Matter Is Made of Black Holes That Survived Dead Universes #BlackHoles #DarkMatter #Éire #EnriqueGaztanaga #Gaztanaga #IE #Ireland #PrimordialBlackHoles #Science #Space
Physicist Proposes Dark Matter Is Made of Black Holes That Survived Dead Universes
Here’s a fun dark matter solution. The invisible and as yet hypothetical substance could be made of “relic”…
#NewsBeep #News #Space #Blackholes #darkmatter #EnriqueGaztanaga #Gaztanaga #primordialblackholes #Science #UK #UnitedKingdom
https://www.newsbeep.com/uk/552809/
https://www.europesays.com/uk/921371/ Physicist Proposes Dark Matter Is Made of Black Holes That Survived Dead Universes #BlackHoles #DarkMatter #EnriqueGaztanaga #Gaztanaga #Physics #PrimordialBlackHoles #Science #UK #UnitedKingdom
Physicist Proposes Dark Matter Is Made of Black Holes That Survived Dead Universes
Here’s a fun dark matter solution. The invisible and as yet hypothetical substance could be made of “relic”…
#NewsBeep #News #Space #AU #Australia #BlackHoles #darkmatter #EnriqueGaztanaga #Gaztanaga #primordialblackholes #Science
https://www.newsbeep.com/au/633503/
Astrophysicists are close to proving the existence of primordial black holes
On November 12, 2025, a ripple passed through the fabric of spacetime and triggered alarms at three gravitational-wave…
#NewsBeep #News #Science #Astronomy #Astrophysics #AU #Australia #blackholemergers #Cosmology #darkmatter #EarlyUniverse #Gravitationalwaves #LIGOdetection #primordialblackholes #research #SpaceNews #spaceresearch #subsolarblackhole
https://www.newsbeep.com/au/574226/
Stephen Hawking writes a tiny paper — and turns our understanding of black holes inside out — March 1, 1974
When you buy through links on our articles, Future and its syndication partners may earn a commission. An…
#NewsBeep #News #Physics #Blackhole #CA #Canada #hawkingradiation #primordialblackholes #Science #StephenHawking
https://www.newsbeep.com/ca/508466/
https://www.europesays.com/uk/797923/ Stephen Hawking writes a tiny paper — and turns our understanding of black holes inside out — March 1, 1974 #BlackHole #HawkingRadiation #Physics #PrimordialBlackHoles #Science #StephenHawking #UK #UnitedKingdom
Stephen Hawking writes a tiny paper — and turns our understanding of black holes inside out — March 1, 1974
When you buy through links on our articles, Future and its syndication partners may earn a commission. An…
#NewsBeep #News #US #USA #UnitedStates #UnitedStatesOfAmerica #Physics #blackhole #hawkingradiation #primordialblackholes #Science #StephenHawking
https://www.newsbeep.com/us/497952/
https://www.europesays.com/ie/362767/ Stephen Hawking writes a tiny paper — and turns our understanding of black holes inside out — March 1, 1974 #BlackHole #Éire #HawkingRadiation #IE #Ireland #Physics #PrimordialBlackHoles #Science #StephenHawking
Explaining the PeV #Neutrino Fluxes at #KM3NeT and #IceCube with Quasi-Extremal #PrimordialBlackHoles: https://arxiv.org/abs/2505.22722 -> Did We Just See a #BlackHole Explode? Physicists at UMass Amherst Think So—and It Could Explain (Almost) Everything: https://www.umass.edu/news/article/did-we-just-see-black-hole-explode-physicists-umass-amherst-think-so-and-it-could -> Something Mysteriously Powerful Slammed Into Earth in 2023. Scientists Now Have a Theory: https://gizmodo.com/something-unimaginably-powerful-slammed-into-earth-in-2023-scientists-now-have-a-theory-2000719040
From the You-didn't-see-this-paper-coming department today: https://arxiv.org/abs/2512.07924 = Microlensing Signatures of Dyson Sphere-like Structures around #PrimordialBlackHoles as Technosignatures of Extraterrestrial Advanced Civilizations -> "Our findings provide a new avenue for searching for extraterrestrial advanced civilizations by extending microlensing studies to include artificial, dynamic modulation signatures" (noting in passing that ET and Dyson Spheres and PBHs are all speculative).
Curious gravitational wave may be hint at primordial black holes - or just noise
It’s a long shot, but scientists may have spotted exotic primordial black holes formed just after the Big Bang. Astronomers approach unusual observation with caution and excitement.
#Physics #GravitationalWaves #BlackHoles #PrimordialBlackHoles #science #news #astrophysics #astrodon #Cosmology
Weekly Update from the Open Journal of Astrophysics – 08/11/2025
It’s Saturday again, so it’s time for the usual update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published another five papers, which brings the number in Volume 8 (2025) up to 168, and the total so far published by OJAp up to 403.
The first paper this week is “Maximizing Ariel’s Survey Leverage for Population-Level Studies of Exoplanets” by Nicolas B. Cowan and Ben Coull-Neveu (McGill University, Canada). This article was published in the folder Earth and Planetary Astrophysics on Tuesday 4th November 2025; it discusses various different schemes to select the mission reference sample for a notional three year transit spectroscopy survey with the European Space Agency’s Ariel mission
The overlay is here:
You can find the officially accepted version on arXiv here.
The Fediverse announcement is here:
Open Journal of Astrophysics
New Publication at the Open Journal of Astrophysics: "Maximizing Ariel’s Survey Leverage for Population-Level Studies of Exoplanets" by Nicolas B. Cowan and Ben Coull-Neveu (McGill University, Canada)
https://doi.org/10.33232/001c.146656
1 boosts 3 favorites
The second paper of the week is “A substellar flyby that shaped the orbits of the giant planets” by Garett Brown (U. Toronto at Scarborough, Canada), Renu Malhotra (U. Arizona, USA) and Hanno Rein (U. Toronto at Scarborough, Canada). This article was published on Wednesday 5th November 2025, also in the folder Earth and Planetary Astrophysics. It argues that an ancient close encounter with a substellar object offers a plausible explanation for the origin of the moderate eccentricities and inclinations of the giant planets.
The overlay is here:
You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:
Open Journal of Astrophysics
New Publication at the Open Journal of Astrophysics: "A substellar flyby that shaped the orbits of the giant planets" by Garett Brown (U. Toronto at Scarborough, Canada), Renu Malhotra (U. Arizona, USA) and Hanno Rein (U. Toronto at Scarborough, Canada)
https://doi.org/10.33232/001c.146688
3 boosts 3 favoritesNext one up is “The Potential Impact of Primordial Black Holes on Exoplanet Systems” by Garett Brown (U. Toronto at Scarborough), Linda He (Harvard U., USA), and James Unwin (U. Illinois Chicago, USA). This one was also published on Wednesday 5th November 2025, but in the folder Astrophysics of Galaxies. This one is an exploration of the possibility that primordial black holes (PBHs) in our Galaxy, might impact the orbits of exoplanets. The overlay is here:
You can find the official accepted version on arXiv here. The fediverse announcement is here:
Open Journal of Astrophysics
New Publication at the Open Journal of Astrophysics: "The Potential Impact of Primordial Black Holes on Exoplanet Systems" by Garett Brown (U. Toronto at Scarborough), Linda He (Harvard U., USA), James Unwin (U. Illinois Chicago, USA)
https://doi.org/10.33232/001c.146689
3 boosts 1 favoritesThe fourth paper to report is “The Unhurried Universe: A Continued Search for Long Term Variability in ASAS-SN” by Sydney Petz, C. S. Kochanek & K. Z. Stanek (Ohio State U., USA), Benjamin J. Shappee (U. Hawaii, USA), Subo Dong (Peking University, China), J. L. Prieto (Universidad Diego Portales, Chile) and Todd A. Thompson (Ohio State U., USA). This one was also published on Wednesday November 5th 2025, but in the folder Solar and Stellar Astrophysics. It describes the discovery and investigation of slowly-varying sources in the All Sky Automated Survey for SuperNovae (ASAS-AN) leading to the identification of 200 new variable stars. The overlay is here:
You can find the official published version on arXiv here. The Fediverse announcement follows:
Open Journal of Astrophysics
New Publication at the Open Journal of Astrophysics: "The Unhurried Universe: A Continued Search for Long Term Variability in ASAS-SN" by Sydney Petz, C. S. Kochanek & K. Z. Stanek (Ohio State U., USA), Benjamin J. Shappee (U. Hawaii, USA), Subo Dong (Peking University, China), J. L. Prieto (Universidad Diego Portales, Chile) and Todd A. Thompson (Ohio State U., USA)
https://doi.org/10.33232/001c.146690
1 boosts 0 favoritesThe fifth and final paper for this week is “Measuring the splashback feature: Dependence on halo properties and history” by Qiaorong S. Yu (Oxford U., UK) and 9 others based in the UK and USA. This was published on Friday 7th November 2025 in the folder Cosmology and Nongalactic Astrophysics. It discusses how the properties of “splashback” features in halo profiles relate to the halo’s assembly history (e.g. mass accretion rate and most recent merger time). The overlay is here:
The officially accepted version can be found on arXiv here. The Fediverse announcement is here:
Open Journal of Astrophysics
New Publication at the Open Journal of Astrophysics: "Measuring the splashback feature: Dependence on halo properties and history" by Qiaorong S. Yu (Oxford U., UK) and 9 others based in the UK and USA.
https://doi.org/10.33232/001c.146824
0 boosts 0 favoritesThat’s all the papers for this week. I’ll do another report next Saturday.
#Ariel #arXiv241204583v2 #arXiv250606429v2 #arXiv250705389v3 #arXiv250707174v2 #arXiv250722102v2 #CosmologyAndNonGalacticAstrophysics #DarkMatterHaloes #DiamondOpenAccess #DiamondOpenAccessPublishing #EarthAndPlanetaryAstrophysics #eccentricity #EuropeanSpaceAgency #exoplanets #ExtrrasolarPlanets #galaxyFormation #galaxyHaloes #GiantPlanets #OpenAccess #OpenJournalOfAstrophysics #primordialBlackHoles #Splashback #TheOpenJournalOfAstrophysics
Ultrahigh-Energy #Neutrinos from #PrimordialBlackHoles: https://journals.aps.org/prl/abstract/10.1103/vnm4-7wdc -> Could a primordial black hole’s last burst explain a mysteriously energetic neutrino? https://news.mit.edu/2025/could-primordial-black-holes-last-burst-explain-mysteriously-energetic-neutrino-0918 - if a new proposal by MIT physicists bears out, the recent detection of a record-setting neutrino could be the first evidence of elusive #HawkingRadiation.
A Primordial Black Hole?
There’s a recent paper on arXiv with the title A direct black hole mass measurement in a Little Red Dot at the Epoch of Reionizationon by Juodžbalis et al. that is causing a lot of interest. The paper is here and the abstract is:
There is a discussion of this in the Grauniad here and in several other places on the interwebs. It comes hard on the heels of the theoretical paper announced here.
I only saw this paper yesterday and, now that I’ve read it, it isn’t really all that clear to me what this object is. No doubt there’ll be considerable follow-up. One possibility – and it is just a possibility – is that we are seeing evidence of a primordial black hole, called a PBH for short. These are black holes formed by direct collapse in the early Universe rather than by merging of stellar black holes. Note the use of the word “naked” is rather misleading. It does not mean a naked singularity, in the sense of a singularity without an event horizon around it. In this case it just means that it appears not to be surrounded by accreting material or even a host galaxy.
A PBH of mass M would form at a particular cosmic time t if a region of radiius ~ct (the cosmological horizon scale) collapses into a black hole. Obviously this would require a large fluctuation in density on that scale but if a PBH does form then its mass will be roughly the mass contained within the horizon, i.e. M ~ ρ(t) (ct)3 (ignoring dimensionless factors). The sort of mass required (~106 M☉) corresponds to a time when the Universe was radiation-dominated and before matter and radiation decoupled. What would be inside such a black hole is therefore predominantly trapped radiation, which is Quite Interesting, but as far as the outside universe is considered it’s just a massive black hole.
Graphic by European Space Agency showing how structure formation might be affected by PBH formationAnyway, during radiation domination, the mass-energy density of the Universe ρ(t) ∝ t-2, so the horizon mass increases linearly with t. According to the standard cosmology, the epoch of radiation domination lasts for approximately 50,000 years after the Big Bang, i.e. of order 1012 seconds, and at the end of it the horizon mass is of order 1014 M☉. Assuming that the universe is completely radiation-dominated before that the time at which a PBH of mass 106 M☉ would form is about 104 seconds, i.e. getting on for 3 hours after the Big Bang. This is after the end of cosmological nucleosynthesis, but not by much. Primordial black holes of lower mass than this would form earlier, with a stellar mass PBH having to collapse around the time of the quark-hadron transition. Lighter PBHs would form even earlier.
The numbers I’ve quoted are very approximate, back-of-the-envelope, ballpark guesstimates. For one thing not all of the horizon mass will end up in a PBH: energy may well be released during the collapse. Moreover, some PBHs on one scale will subsequently be subsumed within objects of larger mass. Also I’ve ignored quite a lot of numerical factors. All this will have to be worked out properly, but there are potential constraints on any physical processes that might give rise to PBHs on the relevant scale if they involve a release of significant amount of energy as there may not be time for this excess to be thermalized by scattering or they may intefere with the element abundances predicted by nucleosynthesis.
That is all assuming it is a primordial black hole in the first place…
#arXiv250821748 #Cosmology #galaxyFormation #matterRadiationEquivalence #PBHs #primordialBlackHoles
Weekly Update from the Open Journal of Astrophysics – 30/08/2025
Once again it’s time for a summary of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published three new papers, which brings the number in Volume 8 (2025) up to 125, and the total so far published by OJAp up to 360.
The first paper to report this week is “Large-scale surveys of the quasar proximity effect” by Rupert Croft, Patrick Shaw & Ann-Marsha Alexis (Carnegie Mellon University; CMU), Nianyi Chen (Princeton), Yihao Zhou & Tiziana Di Matteo (CMU), Simeon Bird (UC Riverside), Patrick Lachance (CMU), and Yueying Ni (Harvard). This paper was published on Monday 25th August in the folder Cosmology and NonGalactic Astrophysics. It presents a CDM-based halo model of the quasar proximity effect, tested on quasar Lyman-alpha spectra from the ASTRID cosmological simulation, including self-consistent formation of quasar black holes and the intergalactic medium.
The overlay is here:
You can make this larger by clicking on it, as you can with all the overlays below. The officially accepted version of this paper can be found on the arXiv here.
The second paper this week, also published on Monday 25th August, but in the folder Astrophysics of Galaxies, is “Redshift evolution of Lyman continuum escape fraction after JWST” by Andrea Ferrara (Pisa), M. Giavalisco (UMass Amherst), L. Pentericci (Rome), E. Vanzella (Bologna), A. Calabrò (Rome) and M. Llerena (Rome). This paper is about the Attenuation-Free Model (AFM) for galaxies, in which radiation-driven outflows develop once the galaxy specific star formation rate exceeds a certain level, which is tested on data with positive results. The overlay is here:
You can find the officially accepted version on arXiv here.
The third and final paper this week is “Primordial black holes in cosmological simulations: growth prospects for supermassive black holes” by Lewis R Prole, John A Regan, Daxal Mehta & Peter Coles (National University of Ireland, Maynooth) and Pratika Dayal (Groningen, NL). This one was published in Astrophysics of Galaxies folder on Thursday 28th August 2025. You can read more about this paper here: basically it studies the growth of primordial black holes in the early Universe using numerical simulations, with implications for the subsequent formation of massive black holes.
The overlay is here:
You can find the officially accepted version of this one on arXiv here.
And that’s all the papers for this week. It’s still a bit slow as we emerge from the summer vacations, but I expect things will start to pick up from now on.
#arXiv250403848v2 #arXiv250510619v2 #arXiv250611233v2 #AstrophysicsOfGalaxies #AttenuationFreeModel #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #JWST #LymanContinuum #massiveBlackHoles #OpenJournalOfAstrophysics #primordialBlackHoles #ProximityEffect #quasars #TheOpenJournalOfAstrophysics
Primordial Black Holes in Cosmological Simulations – Update
Just time for a quick update about a paper that I posted about at the start of the summer, when it appeared on arXiv. At that time it had already gained a bit of traction in the media, e.g. here. Well, the paper is now published in the Open Journal of Astrophysics. Obviously, as an author I was conflicted so not involved in the editorial process.
Here is the overlay:
For those of you not in the field, there is currently a big mystery about how galaxies we have found at high redshift with JWST managed to acquire massive black holes so early in the Universe’s evolution. Black holes can grow quickly in a dense environment by accreting mass onto an initial seed, but what are the seeds? In this paper we investigate the possibility that they were primordial black holes. These form directly from fluctuations in the early Universe, as opposed to astrophysical black holes which form from stellar collapse. We don’t know exactly what mass primordial black holes would have nor how numerous they would be, but this paper uses high-resolution numerical experiments to investigate their effects if they do exist.
Here’s a pretty picture which is a zoom into 200 pc of the full simulation. I think 10pc counts as high resolution for a cosmological simulation! The blue circle shows the most massive PBH in the simulation, the green circle shows its nearest neighbour. The colour scale represents the number-density of dark matter particles.
For more details, read the paper!
Primordial Black Holes in Cosmological Simulations
Being so busy for the last couple of weeks I omitted to engage in the gratuitous self-promotion that one would expect from a blogger, so I’m remedying that today by pointing out that I’m co-author of a new paper that is now on arXiv. This has already gained a bit of traction in the media, e.g. here.
Here is the abstract, which also shows the author list:
(I’ve just noticed that it says “The Netherland”, instead of “The Netherlands”. Oops!)
For those of you not in the field, there is currently a big mystery about how galaxies we have found at high redshift with JWST managed to acquire massive black holes so early in the Universe’s evolution. Black holes can grow quickly in a dense environment by accreting mass onto an initial seed, but what are the seeds? In this paper we investigate the possibility that they were primordial black holes. These form directly from fluctuations in the early Universe, as opposed to astrophysical black holes which form from stellar collapse. We don’t know exactly what mass primordial black holes would have nor how numerous they would be, but this paper uses high-resolution numerical experiments to investigate their effects if they do exist.
Here’s a pretty picture which is a zoom into 200 pc of the full simulation. I think 10pc counts as high resolution for a cosmological simulation! The blue circle shows the most massive PBH in the simulation, the green circle shows its nearest neighbour. The colour scale represents the number-density of dark matter particles.
For more details, read the paper!
P.S. This article has been submitted to the Open Journal of Astrophysics and is currently under review. As an author I am not involved in the editorial process.
✨ Thread Intro: Visualizing Cosmic Inflation and the Big Bang ✨
Ever wondered how our universe began? 🤔
I'm exploring cosmic inflation—the rapid expansion of space driven by the mysterious inflaton field. My short, illustrative video clips represent key stages of this theory, starting from a hypothetical quantum field through inflation, quantum fluctuations, reheating into Big Bang plasma, and formation of tiny primordial black holes (PBHs).
Earlier, I shared a visualization showing how some of these PBHs might have evaporated into Hawking radiation, leaving subtle imprints (Hawking relics) that possibly influenced the formation of the first stars and galaxies. https://hachyderm.io/@suzannealdrich/114235968980503011
👇 Follow along to see each step illustrated clearly and explained scientifically—complete with references to current theories and observational evidence from missions like JWST, DESI, Planck, and more!
Note: These visuals are conceptual illustrations—not literal representations of the extreme energies and forces involved.
#Cosmology #Inflation #BigBang #PrimordialBlackHoles #QuantumPhysics #Astrophysics 🌌🚀🕳️
Weekly Update at the Open Journal of Astrophysics – 22/03/2025
It’s Satuday morning once again, and time for another update of papers published at the Open Journal of Astrophysics. Since the last update we have published two papers, which brings the number in Volume 8 (2025) up to 29 and the total so far published by OJAp up to 264.
The papers we have published this week are connected by the theme of black holes and their role in galaxy formation, which is a very hot topic nowadays!
The first paper to report is “Hawking Radiation from non-evaporating primordial black holes cannot enable the formation of direct collapse black holes” by Jonathan Regan, Marios Kalomenopoulos and Kelly Kosmo O’Neil of the University of Nevada, USA. This paper, which is based on an undergraduate thesis, is a study of the irradiating effects of primordial black holes and a discussion of whether these might influence the subsequent formation of supermassive black holes. It is in the section marked Astrophysics of Galaxies, and was published on Tuesday 18th March.
The overlay is here:
and you can find the final accepted version on arXiv here.
The second paper, which was published on Wednesday 19th March and is also in the folder Astrophysics of Galaxies, is “First Light and Reionization Epoch Simulations (FLARES) – XV: The physical properties of super-massive black holes and their impact on galaxies in the early universe” by Stephen Wilkins & Jussi K. Kuusisto (U. Sussex, UK), Dimitrios Irodotou (Institute of Cancer Research, UK), Shihong Liao (Beijing, China) Christopher C. Lovell (Portsmouth, UK), Sonja Soininen (Insitute of Cancer Research), Sabrina C. Berger (Melbourne, Australia), Sophie L. Newman (Portsmouth, UK), William J. Roper (Sussex), Louise T. C. Seeyave (Sussex), Peter A. Thomas (Sussex) and Aswin P. Vijayan Sussex). This paper uses cosmological hydrodynamical zoom simulations to study the formation of supermassive black holes and their impact on star formation in the early Universe.
Here is the overlay, which you can click on to make larger if you wish:
You can read the officially accepted version of this paper on arXiv here.
That’s all for this week. It’s been a bit frustrating for me as Managing Ediutor, because we have built up a backlog of several papers that were accepted for publication some time ago, but are still waiting for the authors to place the final version on arXiv. I hope these won’t take too long to appear, not least because I would like to clear my workflow on the Scholastica platform!
#arXiv240402815v3 #arXiv241109081v2 #AstrophysicsOfGalaxies #DiamondOpenAccess #FirstLight #FLARES #galaxyFormation #HawkingRadiation #OpenAccessPublishing #OpenJournalOfAstrophysics #primordialBlackHoles #reionization #supermassiveBlackHoles
Researchers provide evidence for primordial black holes in cosmic objects and earthly materials.
https://newstainmentora.blogspot.com/2024/12/researchers-provide-evidence-for.html
#primordialblackholes #blackholes #Cosmic #earth #newstainmentora
Searching for small primordial black holes in planets, asteroids and here on Earth: https://arxiv.org/abs/2409.14321 -> Evidence of #primordialBlackHoles may be hiding in planets, or even everyday objects here on Earth: https://www.buffalo.edu/news/releases/2024/12/primordial-black-holes-may-be-hiding-in-planets-or-even-everyday-objects-here-on-Earth.html
We live in a cyclic universe of a sort because every few years somebody tries to resurrect the idea that dark matter is somehow related to primordial black holes, i.e. black holes formed in the very early stages of the history of the Universe so that they have masses much smaller than black holes formed more recently by the collapse of stars or the merger of other black holes. If it forms very early the mass of a PBH could in principle be very small, much less than a star or a planet. The problem with very small black holes is that they evaporate very quickly via Hawking Radiation so would not survive the 14 billion years or so needed to still be in existence today and able to be dark matter.
An idea that was used in the past to circumvent this issue was that something might stop Hawking Radiation proceeding to reduce the mass of a PBH to zero, leaving a relic of finite mass usually taken to be the Planck mass. The suggestion has returned in different (but still speculative) guise recently, fueling a number of media articles of varying degrees of comprehensibility, e.g. here. The technical papers on which these articles are based can be found here and here.
Fortunately, there is now one of those excellent Cosmology Talks explaining the latest idea of how Hawking Radiation might break down and what the consequences are for Primordial Black Holes as a form of Dark Matter.
https://www.youtube.com/watch?v=p8UhnWri4II
https://telescoper.blog/2024/09/27/dark-matter-from-primordial-black-holes/
#arXiv240214069 #arXiv240217823 #Cosmology #CosmologyTalks #darkMatter #PBH #Physics #primordialBlackHoles #Science #Universe
Close encounters of the primordial kind - a new observable for #PrimordialBlackHoles as dark matter: https://arxiv.org/abs/2312.17217 -> A wobble from #Mars could be sign of dark matter, MIT study finds: https://news.mit.edu/2024/mars-wobble-could-be-dark-matter-mit-study-finds-0917 - watching for changes in the Red Planet’s orbit over time could be new way to detect passing #DarkMatter.
Gravitational Wave Observatories Could Detect Primordial Black Holes Speeding Through the Solar System https://www.universetoday.com/168320/gravitational-wave-observatories-could-detect-primordial-black-holes-speeding-through-the-solar-system/ #primordialblackholes #gravitationalwave #astronomy
🌌 Unraveling the Mysteries of the Early Universe! 🔭 NASA's Roman Space Telescope embarks on a quest to hunt for Primordial Black Holes from the Dawn of Time. 🌌🕳️ #PrimordialBlackHoles #NASARoman #CosmicMysteries #EarlyUniverse #SpaceTelescop
#PrimordialBlackHoles with #QCD Color Charge: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.132.231402#fulltext -> Scientists may have found an answer to the mystery of #DarkMatter: https://edition.cnn.com/2024/06/17/science/black-holes-dark-matter-scn/index.html - it involves an unexpected byproduct.
Roman Space Telescope Will Be Hunting For Primordial Black Holes https://www.universetoday.com/166916/roman-space-telescope-will-be-hunting-for-primordial-black-holes/ #galacticbulgetimedomainsurvey #nancygraceromanspacetelescope #gravitationalmicrolensing #primordialblackholes #rapidinflation #blackholes #darkmatter #cosmology #ogle #moa
Rogue worlds meet the dark side - revealing terrestrial-mass primordial black holes with the Nancy Grace Roman Space Telescope: https://arxiv.org/abs/2311.00751 -> How NASA’s Roman Mission Will Hunt for #PrimordialBlackHoles: https://www.nasa.gov/missions/roman-space-telescope/how-nasas-roman-mission-will-hunt-for-primordial-black-holes/
Planet X? Why not a tiny black hole instead? - Enlarge (credit: NASA)
Planet X has a long and storied history of non-existence. For about 130 ye... - https://arstechnica.com/?p=1699294 #trans-neptunianobjects #primordialblackholes #science #planetx #sedna