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arXiv · 1809.10563

Two-field Cosmological $α$-attractors with Noether Symmetry

Lilia Anguelova·Elena Mirela Babalic·Calin Iuliu Lazaroiu
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Abstract

We study Noether symmetries in two-field cosmological $α$-attractors, investigating the case when the scalar manifold is an elementary hyperbolic surface. This encompasses and generalizes the case of the Poincare disk. We solve the conditions for the existence of a `separated' Noether symmetry and find the form of the scalar potential compatible with such, for any elementary hyperbolic surface. For this class of symmetries, we find that the $α$-parameter must have a fixed value. Using those Noether symmetries, we also obtain many exact solutions of the equations of motion of these models, which were studied previously with numerical methods.

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Lilia Anguelova, Elena Mirela Babalic, Calin Iuliu Lazaroiu. 2019-04-24. Two-field Cosmological $α$-attractors with Noether Symmetry. https://doi.org/10.1007/jhep04(2019)148

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