×

The complex moment problem in the exponential form and inverse spectral problems for the block Jacobi type correspondence matrices. (English) Zbl 1258.47025

The author considers a complex moment problem of the form \[ c_{t,j}=\int_0^\infty \int_0^{2\pi} r^t e^{ij\theta}\,d\rho (r,\theta ),\quad t\in \mathbb Z_+,\;j\in \mathbb Z. \] For this case, an analogue of the correspondence with Jacobi matrices is proposed; there are two corresponding matrices having block three-diagonal structure and acting on the space of \(\ell_2\) type as commuting (bounded) selfadjoint and unitary operators. The moment problem is interpreted in terms of direct and inverse spectral problems for these operators.

MSC:

47A57 Linear operator methods in interpolation, moment and extension problems
47B36 Jacobi (tridiagonal) operators (matrices) and generalizations
30E05 Moment problems and interpolation problems in the complex plane