D. O. E. Silva

The Fourier restriction problem for biradial functions

We determine the exact strong-type Fourier restriction range for the unit sphere $\mathbb{S}^{d-1}$ on the class of $O(d-k)\times O(k)$-invariant functions, for every $d\geq4$ and $2\leq k\leq d-2$. This includes the critical estimates beyond the biradial Stein--Tomas endpoint left open by Mandel and Oliveira e Silva....