Inflationary Twin Models

Abstract

We introduce the concept of inflationary twin models, that is, a class of generalized (kinetic or "K-inflation") field theories which lead exactly to the same cosmological evolution during the inflationary period as a given standard scalar field theory of inflation. The twin concept permits to introduce generalized, K-inflation theories in a controlled manner, maintaining some inflationary predictions unaltered. Further, this concept allows to extend analytical tools like the slow-roll expansion to the realm of K-inflation theories, facilitating their investigation. Twins of a standard scalar field model of inflation still may result in different results for some inflationary observables, because of their nontrivial scalar speed of sound. This implies that non-standard twins may lead to completely viable models of inflation, even if their standard twin is ruled out by observations. We provide some explicit examples of this possibility, including the physical case of a dilaton--Dirac-Born-Infeld theory.

References in corpus (7)

• Observational Signatures and Non-Gaussianities of General Single Field Inflation
• Hidden supersymmetry of domain walls and cosmologies
• Universality classes for models of inflation
• Doppelganger defects
• The First-Order Euler-Lagrange equations and some of their uses
• First-order formalism for dark energy and dust
• On the presence of twinlike models in cosmology

Cited by in corpus (6)

• Centrality dependence of chemical freeze-out parameters and strangeness equilibration in RHIC and LHC energies
• Singular Pöschl-Teller II potentials and gravitating kinks
• New twinlike models for scalar fields
• Twinlike models for parametrized dark energy
• $\beta$-function reconstruction of Palatini inflationary attractors
• Modeling Dark Matter Halos with Nonlinear Field Theories