Vainshtein screening for slowly rotating stars

Understand

We study the Vainshtein mechanism in the context of slowly rotating stars in scalar-tensor theories.

• While the Vainshtein screening is well established for spherically symmetric spacetimes, we examine its validity in the axisymmetric case for slowly rotating sources.
• We show that the deviations from the general relativity solution are small in the weak-field approximation outside the star: the solution for the frame-dragging function is the same as in general relativity at leading order.
• Moreover, in most cases the corrections are suppressed by powers of the Vainshtein radius provided that the screening operates in spherical symmetry.