{"total":14,"items":[{"citing_arxiv_id":"2605.30340","ref_index":47,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Carr criterion and mass gaps in non-singular primordial black hole formation","primary_cat":"gr-qc","submitted_at":"2026-05-28T17:59:17+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":7.0,"formal_verification":"none","one_line_summary":"Non-singular gravity with regulator ℓ induces a PBH mass gap ~c²ℓ/G and a stronger Carr criterion δ_H > 2GM_gap/R_H - 1 when R_H ~ ℓ.","context_count":0,"top_context_role":null,"top_context_polarity":null,"context_text":null},{"citing_arxiv_id":"2605.21474","ref_index":263,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Gravitational Waves from Black Hole Reheating: The Scalar-Induced Component","primary_cat":"hep-ph","submitted_at":"2026-05-20T17:55:24+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":7.0,"formal_verification":"none","one_line_summary":"Accounting for the minimal mass spread of primordial black holes from gravitational collapse suppresses the Poltergeist GW background to the level of generic scalar-induced signals and reopens ultra-light PBH parameter space.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"of heavier BSM particles that would increase this number close to final evaporation, when the PBH temperature increases rapidly. Throughout this work we use the reduced Planck massM pl ≃2.44×10 18 GeV. For simplicity, PBHs are assumed to be non-rotating. This approximation is well justified for PBHs formed via superhorizon collapse, for which the resulting spin distribution peaks well below the percent level,A R <10 −2 [263]. Integrating the mass-loss equation yields the time evolution of the PBH mass 3 MPBH(t) =M PBH,f \u0012 1− t teva \u00131/3 ,(10) whereM PBH,f denotes the PBH mass at formation andt eva is the total PBH lifetime, teva = M 3 PBH,f 3AM 4 pl ≃0.41 s \u0012108 gH⋆ \u0013\u0012 MPBH,f 109 g \u00133 .(11) Using the conformal-time definition in Eq. (8), the evaporation rate can equivalently be ex-"},{"citing_arxiv_id":"2605.14044","ref_index":136,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"The Magnetic Origin of Primordial Black Holes: Ultralight PBHs and Secondary GWs","primary_cat":"astro-ph.CO","submitted_at":"2026-05-13T19:06:49+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":5.0,"formal_verification":"none","one_line_summary":"Inflationary magnetic fields induce curvature perturbations that form ultralight PBHs, generating a stochastic GW background with model-specific features.","context_count":1,"top_context_role":"background","top_context_polarity":"unclear","context_text":"1685 [hep-ph]. [132] S.-L. Cheng, W. Lee, and K.-W. Ng, JHEP02, 008 (2017), arXiv:1606.00206 [astro-ph.CO]. [133] S.-L. Cheng, W. Lee, and K.-W. Ng, JCAP07, 001 (2018), arXiv:1801.09050 [astro-ph.CO]. [134] A. Escriv` a, C. Germani, and R. K. Sheth, Phys. Rev. D101, 044022 (2020), arXiv:1907.13311 [gr-qc]. [135] T. Papanikolaou, Phys. Rev. D105, 124055 (2022). [136] M. Braglia, D. K. Hazra, F. Finelli, G. F. Smoot, L. Sriramkumar, and A. A. Starobinsky, JCAP08, 001 (2020), arXiv:2005.02895 [astro-ph.CO]. [137] A. Karam, N. Koivunen, E. Tomberg, V. Vaskonen, and H. Veerm¨ ae, JCAP03, 013 (2023), arXiv:2205.13540 [astro- 33 ph.CO]. [138] S. Saga, H. Tashiro, and S. Yokoyama, JCAP05, 039 (2020), arXiv:2002.01286 [astro-ph."},{"citing_arxiv_id":"2605.13042","ref_index":30,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"The Gravitational Spectral Radio Forest: A Signature of Primordial Black Holes","primary_cat":"gr-qc","submitted_at":"2026-05-13T05:54:23+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":6.0,"formal_verification":"none","one_line_summary":"Asteroid-mass primordial black holes induce a Riemann tidal splitting of the 2P_{3/2} hydrogen state, turning the 9.9 GHz line into a ~2 GHz bandwidth gravitational spectral radio forest in H II regions with accretion-enhanced emission measure.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"Nore˜ na, JCAP03, 017 (2020), arXiv:1901.05963 [astro- ph.CO]. [27] A. M. Green and A. R. Liddle, Phys. Rev. D56, 6166 (1997), arXiv:astro-ph/9704251. [28] M. Sasaki, T. Suyama, T. Tanaka, and S. Yokoyama, Class. Quant. Grav.35, 063001 (2018), arXiv:1801.05235 [astro-ph.CO]. 11 [29] I. Musco, Phys. Rev. D100, 123524 (2019), arXiv:1809.02127 [gr-qc]. [30] A. Escriv` a, C. Germani, and R. K. Sheth, Phys. Rev. D101, 044022 (2020), arXiv:1907.13311 [gr-qc]. [31] C. T. Byrnes, M. Hindmarsh, S. Young, and M. R. S. Hawkins, JCAP08, 041 (2018), arXiv:1801.06138 [astro-ph.CO]. [32] S. Young, I. Musco, and C. T. Byrnes, JCAP11, 012 (2019), arXiv:1904.00984 [astro-ph.CO]. [33] L. Parker, Phys. Rev. Lett.44, 1559 (1980)."},{"citing_arxiv_id":"2604.27496","ref_index":75,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Primordial black hole dark matter from axion inflation","primary_cat":"astro-ph.CO","submitted_at":"2026-04-30T06:49:42+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":5.0,"formal_verification":"none","one_line_summary":"PBHs generated by axion inflation with gauge-field coupling can comprise all dark matter in the asteroidal mass range while producing a LISA-measurable stochastic GW background.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"Choptuik, Phys. Rev. Lett.70, 9 (1993). [71] C. R. Evans and J. S. Coleman, Phys. Rev. Lett.72, 1782 (1994),gr-qc/9402041. [72] I. Musco, J. C. Miller, and A. G. Polnarev, Class. Quant. Grav.26, 235001 (2009),0811.1452. [73] A. Escriv` a, Universe8, 66 (2022),2111.12693. [74] C. Germani and I. Musco, Phys. Rev. Lett.122, 141302 (2019),1805.04087. [75] A. Escriv` a, C. Germani, and R. K. Sheth, Phys. Rev. D101, 044022 (2020),1907.13311. [76] S. Young, Int. J. Mod. Phys. D29, 2030002 (2019),1905.01230. [77] M. Sasaki, T. Suyama, T. Tanaka, and S. Yokoyama, Class. Quant. Grav.35, 063001 (2018), 1801.05235. [78] B. Carr, A. J. Iovino, G. Perna, V. Vaskonen, and H. Veerm¨ ae (2026),2601.06024. [79] T."},{"citing_arxiv_id":"2604.22634","ref_index":71,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Constraints on the Primordial Black Hole Abundance using Pulsar Parameter Drifts","primary_cat":"astro-ph.CO","submitted_at":"2026-04-24T15:07:45+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":8.0,"formal_verification":"none","one_line_summary":"The first search for scalar-induced gravitational waves via pulsar parameter drifts yields f_PBH < 10^{-10} (95% CL) for PBH masses 0.3 to 4e4 solar masses, strongly disfavoring a primordial black hole origin for LVK binary black holes.","context_count":1,"top_context_role":"method","top_context_polarity":"use_method","context_text":"l , andC th is the critical threshold for collapse. Following [69, 70], we takeC th ≈ 0.58, with the characteristic scale defined by the radius rm at whichCis maximized. Noted that we only consider type I PBHs throughout this Letter. The PBH mass is indicated by the critical collapse scaling relation m=M H κ(C(rm)− C th(rm))γc ,(16) whereκ= 3.3,γ c = 0.36 [71], andM H ≃1.4× 1013M⊙ k/Mpc−1\u0001−2 is the horizon mass at the time of PBH formation. The joint probability density function follows a Gaussian distribution [68] P(C l(rm),C′′ l (rm)) = 1 2πσ0σ2 p 1−γ 2 exp \u0014 − r4 mC′′ l (rm)2 32σ2 2 \u0015 ×exp \" − 1 2(1−γ 2) \u0012 Cl(rm) σ0 +γ r2 mC′′ l (rm) 4σ2 \u00132# . (17) The associated variance parameters are given by σ2"},{"citing_arxiv_id":"2506.15496","ref_index":128,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Thermodynamical uncertainties for primordial black holes from cosmological phase transitions","primary_cat":"hep-ph","submitted_at":"2025-06-18T14:34:48+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":5.0,"formal_verification":"none","one_line_summary":"A state-of-the-art thermodynamic analysis of supercooled phase transitions yields a universal lower bound β/H_* ≃ 5 and shows that viable PBH dark-matter parameter space in classically conformal gauge-Higgs theories is severely limited by percolation and QCD constraints.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"patch exceeds a critical threshold, δc = ρ(tk) − ¯ρ(t) ¯ρ(t) , (25) where ρ(tk) = ρr(tk) + ρv(tk), ¯ρ(t) = ρr(t) + ρv(t) and tk denotes the time at which we evaluate the density contrast when the mode k re-enters the horizon. The threshold δc is determined from numerical relativity using the compaction function at Hubble crossing [127]. In a radiation-dominated Universe, δc ≈ 0.55 [128]. PBH formation requires sufficiently large late- blooming regions of false vacuum, screened by surround- ing regions of true vacuum, to collapse [62]. If a true vac- uum bubble nucleates too early, the region may not reach the necessary overdensity. As pointed out in [70], PBH formation may not only result from an overdensity inside a false vacuum region; rather, one must also consider the"},{"citing_arxiv_id":"2505.16820","ref_index":251,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Isotropy, anisotropies and non-Gaussianity in the scalar-induced gravitational-wave background: diagrammatic approach for primordial non-Gaussianity up to arbitrary order","primary_cat":"astro-ph.CO","submitted_at":"2025-05-22T15:55:50+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":6.0,"formal_verification":"none","one_line_summary":"Extends diagrammatic approach for scalar-induced gravitational waves to arbitrary-order local PNG, deriving semi-analytic spectra for energy density, anisotropies, bispectrum and trispectrum up to quartic terms.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"trum represented byP X−like(X=C,Z,P,N,CZ,PZ,NC) with that expressed in terms of gNL andτNL, specifically focusing on their respective contributions to the energy-density full spectrum ¯ωgw,in. Furthermore, we discuss the pure impacts of the primordial trispectrum on the SIGW background. As is customarily done, the primordial trispectrum for local-type PNG is expressed in the form outlined by [158, 251, 252], i.e., TζS(k1,k 2,k 3,k 4) =τNL (PζS(|k1 +k 3|)PζS(k3)PζS(k4) + 11perms) +54gNL 25 (PζS(k2)PζS(k3)PζS(k4) + 3perms),(6.3) whereτNL satisfies the conditionτNL≥(6fNL/5)2 [252, 253]. This condition, derived from theδNformalism [150-153], holds as long as the PNG arises from super-horizon evolution. The equality in this condition holds for single-field inflation models and certain special multi-"},{"citing_arxiv_id":"2505.08011","ref_index":46,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Primordial black holes and magnetic fields in conformal neutrino mass models","primary_cat":"hep-ph","submitted_at":"2025-05-12T19:24:16+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":5.0,"formal_verification":"none","one_line_summary":"Conformal U(1)' seesaw models produce PBHs contributing to dark matter and helical magnetic fields at seesaw scales of 10^4-10^11 GeV, with observable GW, microlensing, and Hawking signals at LISA, Roman, and future gamma-ray telescopes.","context_count":0,"top_context_role":null,"top_context_polarity":null,"context_text":null},{"citing_arxiv_id":"2503.01962","ref_index":69,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Curvature Perturbations from First-Order Phase Transitions: Implications to Black Holes and Gravitational Waves","primary_cat":"hep-ph","submitted_at":"2025-03-03T19:00:01+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":6.0,"formal_verification":"none","one_line_summary":"Covariant analysis of curvature perturbations from first-order phase transitions reveals gauge-dependent overestimation of primordial black holes and gravitational waves in prior non-covariant calculations, leading to strong suppression of both signals.","context_count":0,"top_context_role":null,"top_context_polarity":null,"context_text":null},{"citing_arxiv_id":"2502.20166","ref_index":79,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Numerical simulations of density perturbation and gravitational wave production from cosmological first-order phase transition","primary_cat":"hep-ph","submitted_at":"2025-02-27T15:04:55+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":5.0,"formal_verification":"none","one_line_summary":"3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.","context_count":0,"top_context_role":null,"top_context_polarity":null,"context_text":null},{"citing_arxiv_id":"2109.01398","ref_index":214,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Scalar induced gravitational waves review","primary_cat":"gr-qc","submitted_at":"2021-09-03T09:44:21+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":2.0,"formal_verification":"none","one_line_summary":"A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"The fraction of Hubble patches where PBH forms is exponentially suppressed and sensitive to the root mean squared of the distribution, which is related to the power spectrum. This is why we generally needPR∼ 10−2 to form a substantial fraction of PBHs. Precise estimations of the fraction of PBH is an active and ongoing research field, e.g., see Refs. [202,214-221] and references therein. For our purposes, it is enough to know that only large induced GWs have a large associated fraction of PBH and, inversely, the absence of large induced GWs rules out PBHs from large primordial fluctuations. For simplicity, we continue with the assumptions of the previous section and take a primordial spectrum with a Dirac delta peak atkp."},{"citing_arxiv_id":"2006.02838","ref_index":68,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Primordial Black Holes as Dark Matter: Recent Developments","primary_cat":"astro-ph.CO","submitted_at":"2020-06-03T17:57:28+00:00","verdict":"UNVERDICTED","verdict_confidence":"LOW","novelty_score":3.0,"formal_verification":"none","one_line_summary":"Primordial black holes in specific mass ranges could account for some or all dark matter while resolving structure-formation and seed problems in standard cosmology.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"[66] Ilia Musco, \"Threshold for primordial black holes: Dependence on the shape of the cosmological perturba- tions,\" Phys. Rev. D 100, 123524 (2019), arXiv:1809.02127 [gr-qc]. [67] Albert Escriva, Cristiano Germani, and Ravi Sheth, \"Universal threshold for primordial black hole forma- tion,\" Phys. Rev. D 101, 044022 (2020), arXiv:1907.13311 [gr-qc]. [68] Albert Escriv, Cristiano Germani, and Ravi Sheth, \"Analytical thresholds for black hole formation in general cosmological backgrounds,\" (2020), arXiv:2007.05564 [gr-qc]. [69] Vicente Atal and Cristiano Germani, \"The role of non-gaussianities in Primordial Black Hole formation,\" Phys. Dark Univ. 24, 100275 (2019), arXiv:1811.07857 [astro-ph.CO]. [70] Alex Kehagias, Ilia Musco, and Antonio Riotto, \"Non-Gaussian Formation of Primordial Black Holes:"},{"citing_arxiv_id":"2002.12778","ref_index":41,"ref_count":1,"confidence":0.9,"is_internal_anchor":false,"paper_title":"Constraints on Primordial Black Holes","primary_cat":"astro-ph.CO","submitted_at":"2020-02-27T05:17:54+00:00","verdict":"ACCEPT","verdict_confidence":"MODERATE","novelty_score":4.0,"formal_verification":"none","one_line_summary":"Updated compilation shows PBHs are tightly constrained across 55 orders of magnitude in mass, ruling out dominant dark matter contributions except in narrow windows, with many limits carrying observational uncertainties.","context_count":1,"top_context_role":"background","top_context_polarity":"background","context_text":"37-0.43. Subsequent work considered the relationship between the threshold and curvature profile more precisely and obtained 0.4-2/3 [38], with an analytic expression being obtained in Ref. [39]. In the context of inflationary scenarios, it was also shown that the collapse fraction depends on the shape of the peak in the power spectrum [40]. Recent work [41] uses numerical simulations to derive a simple expression for δc which accounts for the non-linear relation between the curvature perturbation and the density contrast and for non-linear effects arising at horizon crossing. The value of δc could also be affected by non-Gaussianity, this slightly changing the relationship between the curvature perturbation"}],"limit":50,"offset":0}