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arXiv · 1902.05031

A quasi-matter bounce equivalent to Starobinsky inflation

L. F. Guimarães·F. T. Falciano·G. Brando
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Abstract

In this paper we construct a bounce model that mimics the Starobinsky inflationary model. Our construction relies on Wands' duality, which shows that the Mukhanov-Sasaki equation has a symmetry transformation by changing appropriately its time-dependent mass term. One of the advantages of this constructive method is that one can control every contribution to the primordial power spectrum and check how far we can emulate a given primordial model with a different scenario. In particular, we show that mapping the Starobinsky inflation into a quasi-matter bounce gives the correct relation between the scalar spectral index $n_s-1$ and the tensor-to-scalar ratio $r$.

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L. F. Guimarães, F. T. Falciano, G. Brando. 2019-02-13. A quasi-matter bounce equivalent to Starobinsky inflation. https://doi.org/10.1103/physrevd.99.103515

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