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arXiv · 2203.06349

Large Spin-2 Signals at the Cosmological Collider

Xi Tong·Zhong-Zhi Xianyu
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Abstract

We study the theory and phenomenology of massive spin-2 fields during the inflation with nonzero background chemical potential, and extend the cosmological collider physics to tensor modes. We identify a unique dimension-5 and parity-violating chemical potential operator for massive spin-2 fields, which leads to a ghost-free linear theory propagating one scalar mode and two tensor modes. The chemical potential greatly boosts the production of one tensor mode even for very heavy spin-2 particles, and thereby leads to large and distinct cosmological collider signals for massive spin-2 particles. The large signals show up at the tree-level in both the curvature trispectrum and the tensor-curvature mixed bispectrum.

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Xi Tong, Zhong-Zhi Xianyu. 2022-03-12. Large Spin-2 Signals at the Cosmological Collider. https://doi.org/10.1007/jhep10(2022)194

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