Conformal inflation with chameleon coupling

Understand

We investigate the possibility that the inflaton, in particular in conformal inflation models, is also a chameleon, i.e.

• that it couples to the energy density of some heavy non-relativistic matter present during inflation.
• We find new and interesting attractor behaviours, either prolonging inflation, or changing the observables $n_s,r$, depending on the sign of the chameleon coupling exponent.
• We also check that the chameleon coupling with the heavy matter field strongly suppress entropy modes during inflation.