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arXiv · 1804.07740

Berry phase of primordial scalar and tensor perturbations in single-field inflationary models

Hamideh Balajani·Mohammad Mehrafarin
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Abstract

In the framework of the single-field slow-roll inflation, we derive the Hamiltonian of the linear primordial scalar and tensor perturbations in the form of time-dependent harmonic oscillator Hamiltonians. We find the invariant operators of the resulting Hamiltonians and use their eigenstates to calculate the adiabatic Berry phase for sub-horizon modes in terms of the Lewis-Riesenfeld phase. We conclude by discussing the discrepancy in the results of Pal et. al [Class. Quant. Grav. 30 (2013) 12] for these Berry phases, which is resolved to yield agreement with our results.

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Hamideh Balajani, Mohammad Mehrafarin. 2018-04-20. Berry phase of primordial scalar and tensor perturbations in single-field inflationary models. https://arxiv.org/abs/1804.07740

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