Superhorizon Isocurvature as a Window into Dark Matter Production

arXiv:2510.21917 · hep-ph, astro-ph.CO · Submitted 2025-10-24 · Read on arXiv

hep-ph, astro-ph.CO

Submitted: 2025-10-24

Updated: 2026-09-08

Comments: 22 pages, 9 figures. v2: Minor revisions: corrected typo, added limit to analytic calculation, expanded discussion. Results and conclusions unchanged

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Abundance — 24× in this paper · explained in 1 episode
• Non-Gaussianity — 4× in this paper · explained in 2 episodes
• Phase Transitions — 4× in this paper · explained in 2 episodes
• Hubble Tension — 3× in this paper · explained in 9 episodes
• Reheating — 3× in this paper · explained in 2 episodes
• Decoupling — 2× in this paper · explained in 2 episodes
• Degeneracy — 2× in this paper · explained in 3 episodes
• Primordial non-Gaussianity — 2× in this paper · explained in 2 episodes
• Spectral Distortions — 2× in this paper · explained in 2 episodes
• Benchmark — 1× in this paper · explained in 2 episodes
• Boltzmann Equation — 1× in this paper · explained in 2 episodes
• Domain Walls — 1× in this paper · explained in 2 episodes
• Nonminimal coupling — 1× in this paper · explained in 2 episodes
• Trace — 1× in this paper · explained in 2 episodes

Sources

• Planck 2018 results. VI. Cosmological parameters
• Planck 2018 results. X. Constraints on inflation
• Improved cosmological constraints from a joint analysis of the SDSS-II and SNLS supernova samples
• DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations
• CMB spectral distortions from small-scale isocurvature fluctuations
• BBN constraints on dark radiation isocurvature
• One $\mu$ to rule them all: CMB spectral distortions can probe domain walls, cosmic strings and low scale phase transitions
• Isocurvature perturbations in extra radiation
• DESI DR2 Results II: Measurements of Baryon Acoustic Oscillations and Cosmological Constraints
• General Constraints on Isocurvature from the CMB and Ly-$\alpha$ Forest
• Future constraints on neutrino isocurvature perturbations in the curvaton scenario
• Non-Gaussian isocurvature perturbations in dark radiation
• Free-streaming and Coupled Dark Radiation Isocurvature Perturbations: Constraints and Application to the Hubble Tension
• Dark Matter and Gravity Waves from a Dark Big Bang
• Finite Bubble Statistics Constrain Late Cosmological Phase Transitions
• Dark Radiation Isocurvature from Cosmological Phase Transitions
• Axion Cosmology
• Cosmology of axion dark matter
• Minimal solution to the axion isocurvature problem from a nonminimal coupling
• Gravitational waves from a universe filled with primordial black holes

Related papers

• Classification of g-modes for neutron stars with a strong transition: Novel universal relation including slow stable hybrid stars
• Higgsino Dark Matter Interpretation of the LUX-ZEPLIN 248 keV Nuclear-Recoil Event
• A Unified Bogoliubov Approach to Primordial Gravitational Waves: From Inflation to Reheating
• Probing Memory-Burdened Primordial Black Holes with High-Energy Neutrinos
• Enhanced Dark Matter Quantum Sensing via Phase-Space Geometric Interferometry
• Axions as Dark Matter, Dark Energy, and Dark Radiation