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arXiv · 1808.05134

Preinflationary dynamics in loop quantum cosmology: Monodromy Potential

Abstract

In this article we explore the pre-inflationary background dynamics of an FLRW universe sourced by a scalar field with monodromy potential in LQC framework. In particular we calculate the number of e-folds, $N_{inf}$, produced during the slowly rolling phase of the inflation and find out the critical value of the ratio of the kinetic to potential energy, $r_w^c$, at the quantum bounce that is required to produce $N_{inf}\simeq 60.$ Two different monodromy potentials, namely, linear and quadratic with a modulation term are investigated to this effect. The effects on the value of $N_{inf}$ due to parameters associated with the strength, decay constant and the phase factor of the modulation term are calculated. In addition to this we present the qualitative picture of the background dynamics by carrying out a dynamical system analysis. We produce the phase portraits and carry out a detailed linear stability analysis of the finite fixed points, if any, for each of the potentials.

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Manabendra Sharma, M. Shahalam, Wu Qiang, Anzhong Wang. 2018-10-23. Preinflationary dynamics in loop quantum cosmology: Monodromy Potential. https://doi.org/10.1088/1475-7516%2F2018%2F11%2F003

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