Pith. sign in

REVIEW 9 cited by

Fuzzy Axions and Associated Relics

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2412.12012 v1 pith:W3CNQSS2 submitted 2024-12-16 hep-th astro-ph.COhep-ph

Fuzzy Axions and Associated Relics

classification hep-th astro-ph.COhep-ph
keywords axionsfuzzydarkaxionmattermodelscalabi-yaucompactifications
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

We study fuzzy axion dark matter in type IIB string theory, for axions descending from the Ramond-Ramond four-form in compactifications on orientifolds of Calabi-Yau hypersurfaces. Such models can be tested by cosmological measurements if a significant relic abundance of fuzzy dark matter arises, which we argue is most common in models with small numbers of axions. We construct a topologically exhaustive ensemble of more than 350,000 Calabi-Yau compactifications yielding up to seven axions, and in this setting we perform a systematic analysis of misalignment production of fuzzy dark matter. In typical regions of moduli space, the fuzzy axion, the QCD axion, and other axions have comparable decay constants of $f_a \approx 10^{16}$ GeV. We find that overproduction of heavier axions is problematic, except at special loci in moduli space where decay constant hierarchies can occur: without a contrived reheating epoch, it is necessary to fine-tune initial displacements. The resulting dark matter is typically a mix of fuzzy axions and heavier axions, including the QCD axion. Dark photons are typically present as a consequence of the orientifold projection. We examine the signatures of these models by simulating halos with multiple fuzzy axions, and by computing new cosmological constraints on ultralight axions and dark radiation. We also give evidence that cosmic birefringence is possible in this setting. Our findings determine the phenomenological correlates of fuzzy axion dark matter in a corner of the landscape.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 9 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Growth of Structure in Multi-species Wave Dark Matter

    astro-ph.CO 2025-10 unverdicted novelty 7.0

    Derives the power spectrum evolution and cross-spectra for arbitrary multi-species wave and particle dark matter, incorporating free-streaming, Jeans scales, and intrinsic fluctuations.

  2. Testing F-theory GUTs with the Axiverse

    hep-th 2026-06 unverdicted novelty 6.0

    In F-theory GUTs, non-universal ALPs induced by hypercharge flux satisfy g_aγ/m_a well below the QCD axion prediction when gauge couplings unify near the string scale.

  3. Counting axions with IAXO

    hep-ph 2026-06 unverdicted novelty 5.0

    Projections for IAXO in two-axion parameter space plus spectral analysis of flavor oscillations show where the experiment can discriminate multi-axion signals from single-axion ones, extending to N-axion cases.

  4. Tachyonic Encore: A universal shift of inflationary observables

    hep-th 2026-06 unverdicted novelty 5.0

    A light axion spectator induces post-inflation tachyonic phases that produce a nearly scale-invariant boost to the curvature power spectrum and alter key inflationary observables in a largely potential-independent manner.

  5. The Atacama Cosmology Telescope: Probing new signatures of ultralight axions with gravitational lensing

    astro-ph.CO 2026-06 unverdicted novelty 5.0

    New upper limits on ultralight axion dark matter fraction (<1.5% at 10^{-26} eV, <9% at 10^{-25} eV at 95% CL) from combined CMB lensing data, plus marginal 2.1σ preference at 10^{-24.5} eV driven by few points.

  6. Sharpening the Supersymmetric Axion Weak Gravity Conjecture

    hep-th 2026-05 unverdicted novelty 5.0

    The paper verifies the bound fS/|n| ≤ (π/(2 κ_d)) sqrt((d-1)/(d-2)) for axion instantons and sharpens it to fS/|n| ≤ (1/κ_4) sqrt(7/2) for supersymmetric 4d instantons using three approaches in the string landscape.

  7. Probing High-Quality Axions with Gravitational Waves

    hep-ph 2026-04 unverdicted novelty 5.0

    High-quality axion models with N_DW=1 and dark matter abundance requirement restrict the gauge breaking scale to 1.6e11-1e16 GeV, yielding a band of gravitational wave signals from two-step phase transitions consisten...

  8. Nucleosynthesis and CMB bounds on photophilic ALPs: a fresh look

    hep-ph 2025-10 unverdicted novelty 5.0

    Updated model-independent BBN and CMB bounds on photophilic ALPs that incorporate rare decays to light hadrons, show extended constraints for multiple reheating temperatures, and flag parameter space that may alleviat...

  9. Axions at the meV Crossroads: Theory, Cosmology, Astrophysics, and Experiments

    hep-ph 2026-03 conditional novelty 2.0

    The meV axion window is presented as a coherent, cross-validated search program in which string theory, stellar cooling, dark matter, and new detector concepts converge on the same mass range.