Gauge invariant fluctuations of the metric during inflation from new scalar-tensor Weyl-Integrable gravity model

MAURICIO BELLINI; CARLOS AUGUSTO ROMERO FILHO; MARÍA LAURA PUCHEU; JOSÉ EDGAR MADRIZ AGUILAR

PHYSICAL REVIEW D - PARTICLE AND FILDS

American Physical Society

Lugar: Washington; Año: 2016 vol. 94 p. 64075 - 64081

0556-2821

We investigate gauge invariant scalar fluctuations of the metric duringinflation in a non-perturbative formalism in the framework of a recentlyformulated scalar-tensor theory of gravity, in which the geometry of spacetimeis that of a Weyl integrable manifold. We show that in this scenario the Weylscalar field can play the role of the inflaton field. As an application of thetheory, we examine the case of a power law inflation. In this case, thequasi-scale invariance of the spectrum for scalar fluctuations of the metricis achieved for determined values of the parameter $omega$ of thescalar-tensor theory. We stress the fact that in our formalism the physicalinflaton field has a purely geometrical origin.