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A<sc>bstract</sc> The phenomenon of cosmological gravitational particle production (CGPP) is expected to occur during the period of inflation and the transition into a hot big bang cosmology. Particles may be produced even if they only couple directly to gravity, and so CGPP provides a natural explanation for the origin of dark matter. In this work we study the gravitational production of massive spin-2 particles assuming two different couplings to matter. We evaluate the full system of mode equations, including the helicity-0 modes, and by solving them numerically we calculate the spectrum and abundance of massive spin-2 particles that results from inflation on a hilltop potential. We conclude that CGPP might provide a viable mechanism for the generation of massive spin-2 particle dark matter during inflation, and we identify the favorable region of parameter space in terms of the spin-2 particle’s mass and the reheating temperature. As a secondary product of our work, we identify the conditions under which such theories admit ghost or gradient instabilities, and we thereby derive a generalization of the Higuchi bound to Friedmann-Robertson-Walker (FRW) spacetimes.
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This content will become publicly available on January 7, 2026
A universal feature for the Higgs phenomenon in Anti de Sitter space
Abstract In Anti de Sitter space both massive and massless high-spin particles can have consistent local interactions. Both can couple to conserved currents. In this paper we show that when the particles have spin one or greater, there exists a universal feature associated to the particle becoming massive: the currents possess a non-vanishing boundary flux.
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- Award ID(s):
- 2210349
- PAR ID:
- 10613037
- Editor(s):
- Henneaux, M; Nepomechie, R; Seminara, D
- Publisher / Repository:
- IOP Publishing Ltd
- Date Published:
- Journal Name:
- Journal of Physics A: Mathematical and Theoretical
- Edition / Version:
- 1
- Volume:
- 58
- Issue:
- 3
- ISSN:
- 1751-8113
- Page Range / eLocation ID:
- 035401
- Format(s):
- Medium: X Size: 399KB Other: pdf
- Size(s):
- 399KB
- Sponsoring Org:
- National Science Foundation
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