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Affleck-Dine curvaton

Aurora Ireland1,*, Gordan Krnjaic2,3,4,†, and Takuya Okawa2,5,‡

  • *Contact author: anireland@stanford.edu
  • †Contact author: krnjaicg@uchicago.edu
  • ‡Contact author: o.takuya@wustl.edu
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Phys. Rev. D 113, 103537 – Published 27 May, 2026

DOI: https://doi.org/10.1103/7hr7-rtvh

Abstract

The Standard Model of particle physics does not explain the origin of the universe’s baryon asymmetry or its primordial fluctuations. The Affleck-Dine mechanism is a well motivated scenario for generating the baryon asymmetry through the postinflationary dynamics of a complex scalar field with baryon number. The curvaton mechanism is a popular approach for producing curvature perturbations through the dynamics of a light spectator field that decays after inflation. We demonstrate that the same complex field can viably perform both roles without any modifications to the minimal realization of Affleck-Dine baryogenesis. This scenario can also accommodate appreciable levels of primordial non-Gaussianity, beyond those achievable with only a real-valued curvaton field, and may be observable with future cosmic microwave background experiments.

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Phys. Rev. D 113, 103537– Published 27 May, 2026
  • Received 28 July 2025
  • Accepted 16 March 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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