Waterfall stiff period can generate observable primordial gravitational waves

Dimopoulos, Konstantinos (2022) Waterfall stiff period can generate observable primordial gravitational waves. Journal of Cosmology and Astroparticle Physics, 2022 (10). ISSN 1475-7516

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Abstract

Abstract: A toy-model is studied, which considers two flat directions meeting at an enhanced symmetry point such that they realise the usual hybrid inflation mechanism. The kinetic term of the waterfall field features a pole at its Planckian vacuum expectation value (VEV), as with α-attractors. Consequently, after the phase transition which terminates hybrid inflation, the waterfall field never rolls to its VEV. Instead, it drives a stiff period, where the barotropic parameter of the Universe w ≈ 1/2 results in a peak in the spectrum of primordial gravitational waves, which will be observable by the forthcoming LISA mission as well as by Advanced LIGO.

Item Type:
Journal Article
Journal or Publication Title:
Journal of Cosmology and Astroparticle Physics
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/3100/3103
Subjects:
ID Code:
177389
Deposited By:
Deposited On:
11 Oct 2022 16:05
Refereed?:
Yes
Published?:
Published
Last Modified:
22 Nov 2022 11:56