Chaotic inflation with four-form couplings

Understand

We consider chaotic inflation models with a pseudo-scalar field containing the general couplings to the four-form flux.

• The four-form mixing with the pseudo-scalar field induces a quadratic potential for inflaton while the coexisting four-form mixing with graviton generates a non-minimal gravity coupling for inflaton.
• The shift symmetry is respected by the derived inflaton couplings and it is broken spontaneously only by the fixed four-form flux.
• We discuss the success of inflationary predictions and robustness against higher order terms.