Constraining tachyonic inflationary β-exponential model with Continuous Spontaneous Localization collapse scheme

Abstract

In this work, we consider the dynamics of the self-induced collapse of the tachyon wave function in inflationary scenarios. We analyze the modifications on the power spectrum by considering the ${\hat{I}}^2$-exponential potential, whose parameters have updated constraints by the Planck 2018 baseline data and recent results from the Atacama Cosmology Telescope (ACT). Moreover, we show that for this kind of potential, just for a narrow range of ${\hat{I}}^2$-parameter, there is agreement between the theoretical predictions and the current observational data. Considering the proposal for a collapse scheme that leads to the modification of Schrödinger evolution of the inflation wave function from the employment of a Continuous Spontaneous Localization (CSL) approach, we derive the scalar spectral index and tensor-to-scalar ratio. We then obtained the constraints on both collapse and ${\hat{I}}^2$-parameters that, in turn, yield deviations in the $n_s$ vs. $r$ plane when compared to the ${\hat{I}}^2$-exponential potential standard estimate. The CSL scheme applied to tachyonic inflation driven by a ${\hat{I}}^2$-potential offers an adequate description of the recent data.

19 pages, 4 figures; Published in the Modern Physics Letters A