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arXiv · 2312.08430

Coherent spin states and emergent de Sitter quasinormal modes

Klaas Parmentier
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Abstract

As a toy model for the microscopic description of matter in de Sitter space, we consider a Hamiltonian acting on the spin-j representation of SU(2). This is a model with a finite-dimensional Hilbert space, from which quasinormal modes emerge in the large-spin limit. The path integral over coherent spin states can be evaluated at the semiclassical level and from it we find the single-particle de Sitter density of states, including 1/j corrections. Along the way, we discuss the use of quasinormal modes in quantum mechanics, starting from the paradigmatic upside-down harmonic oscillator.

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Klaas Parmentier. 2023-12-13. Coherent spin states and emergent de Sitter quasinormal modes. https://arxiv.org/abs/2312.08430

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