Abstract:
In a wide class of block Jacobi matrices, an estimate of norms of Green matrix (resolvent) entries is proved, which depends on the rate of growth of norms of the off-diagonal entries of the matrix and on the distance from the spectral parameter to the essential spectrum if the latter is nonempty. The sharpness of this estimate is shown by an example.
The first author was supported by the RFBR 19-01-00657A grant as well as by the Knut and Alice Wallenberg Foundation (§§1–2) and by the RScF 20-11-20032 grant (§§3–4). The second author was supported by the RFBR 19-01-00565A grant (§§1–2) and by the RScF 20-11-20032 grant (§§3–4).
Citation:
S. N. Naboko, S. Simonov, “Estimates of Green matrix entries of selfadjoint unbounded block Jacobi matrices”, Algebra i Analiz, 35:1 (2023), 243–261; St. Petersburg Math. J., 35:1 (2024), 185–199