TY - JOUR

T1 - Superradiance in string theory

AU - Mehta, Viraf M.

AU - Demirtas, Mehmet

AU - Long, Cody

AU - Marsh, David J.E.

AU - McAllister, Liam

AU - Stott, Matthew J.

N1 - Publisher Copyright:
© 2021 IOP Publishing Ltd and Sissa Medialab.

PY - 2021/7

Y1 - 2021/7

N2 - We perform an extensive analysis of the statistics of axion masses and interactions in compactifications of type IIB string theory, and we show that black hole superradiance excludes some regions of Calabi-Yau moduli space. Regardless of the cosmological model, a theory with an axion whose mass falls in a superradiant band can be probed by the measured properties of astrophysical black holes, unless the axion self-interaction is large enough to disrupt formation of a condensate. We study a large ensemble of compactifications on Calabi-Yau hypersurfaces, with 1 ≤ h 1,1 ≤ 491 closed string axions, and determine whether the superradiance conditions on the masses and self-interactions are fulfilled. The axion mass spectrum is largely determined by the Kahler parameters, for mild assumptions about the contributing instantons, and takes a nearly-universal form when h 1,1 ≫ 1. When the Kahler moduli are taken at the tip of the stretched Kahler cone, the fraction of geometries excluded initially grows with h 1,1, to a maximum of ≈ 0.5 at h 1,1 ≈ 160, and then falls for larger h 1,1. Further inside the Kahler cone, the superradiance constraints are far weaker, but for h 1,1 ≫ 100 the decay constants are so small that these geometries may be in tension with astrophysical bounds, depending on the realization of the Standard Model.

AB - We perform an extensive analysis of the statistics of axion masses and interactions in compactifications of type IIB string theory, and we show that black hole superradiance excludes some regions of Calabi-Yau moduli space. Regardless of the cosmological model, a theory with an axion whose mass falls in a superradiant band can be probed by the measured properties of astrophysical black holes, unless the axion self-interaction is large enough to disrupt formation of a condensate. We study a large ensemble of compactifications on Calabi-Yau hypersurfaces, with 1 ≤ h 1,1 ≤ 491 closed string axions, and determine whether the superradiance conditions on the masses and self-interactions are fulfilled. The axion mass spectrum is largely determined by the Kahler parameters, for mild assumptions about the contributing instantons, and takes a nearly-universal form when h 1,1 ≫ 1. When the Kahler moduli are taken at the tip of the stretched Kahler cone, the fraction of geometries excluded initially grows with h 1,1, to a maximum of ≈ 0.5 at h 1,1 ≈ 160, and then falls for larger h 1,1. Further inside the Kahler cone, the superradiance constraints are far weaker, but for h 1,1 ≫ 100 the decay constants are so small that these geometries may be in tension with astrophysical bounds, depending on the realization of the Standard Model.

KW - astrophysical black holes

KW - dark matter theory

KW - string theory and cosmology

KW - xions

UR - http://www.scopus.com/inward/record.url?scp=85118409630&partnerID=8YFLogxK

U2 - 10.1088/1475-7516/2021/07/033

DO - 10.1088/1475-7516/2021/07/033

M3 - Article

AN - SCOPUS:85118409630

SN - 1475-7516

VL - 2021

JO - Journal of Cosmology and Astroparticle Physics

JF - Journal of Cosmology and Astroparticle Physics

IS - 7

M1 - 033

ER -