Palatini formulation for gauge theory: implications for slow-roll inflation by Syksy Rasanen et al. on Wednesday 30 November

We consider a formulation of gauge field theory where the gauge field

$A_\alpha$ and the field strength $F_{\alpha\beta}$ are independent variables,

as in the Palatini formulation of gravity. For the simplest gauge field action,

this is known to be equivalent to the usual formulation. We add non-minimal

couplings between $F_{\alpha\beta}$ and a scalar field, solve for

$F_{\alpha\beta}$ and insert it back into the action. This leads to modified

gauge field and scalar field terms. We consider slow-roll inflation and show

that because of the modifications to the scalar sector, adding higher order

terms to the inflaton potential does not spoil its flatness, unlike in the

usual case. Instead they make the effective potential closer to quadratic. The

modifications also solve the problem that Higgs inflation in the Palatini

formulation is sensitive to higher order terms.

arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.15584v1