Аннотация:
We give the solution of the Turán, Fejér, Delsarte, Logan, and Bohman
extremal problems for the Fourier transform on the hyperboloid
$\mathbb{H}^{d}$
or Lobachevsky space.
We apply the averaging function method over the sphere
and the solution of these problems for the Jacobi transform on the
half-line.