Extranatural Warped Inflation

We investigate whether inflation in the early universe can be induced by an extra component of a five-dimensional $\mathrm{U}(1)$ gauge field in the Randall-Sundrum warped spacetime or not. We show that an effective potential obtained by quantum corrections can act as an inflaton potential by finding parameter regions consistent with Planck 2018 results. In our model, fields involved in inflation obey a different type of boundary condition from that of the visible particles, and a surviving Wilson line phase can play a specific role for physics beyond the standard model.