B. Mityagin

collaborators

5 papers

math.SP2026

Eigensystems of Dirac operators with singular potentials

Boris Mityagin, Petr Siegl

We perturb one-dimensional Dirac operators on a bounded interval subject to Dirichlet boundary conditions by potentials with Fourier coefficients exhibiting power-decay. As a conse…

math.CV2026

Estimates of $I^$ -functions and their $lo g$ -derivatives

Miron Bekker, Boris Mityagin

We provide a lower bound for a weighted ratio of $I^ -$ functions and its $lo g -$ derivative. Then we apply this result to estimate the norm of the operator associated with the CesÃ…

math.SP2026

Riesz property in the case of multiple eigenvalues

Boris Mityagin, Petr Siegl

We analyze spectra and the Riesz property of spectral projections of non-symmetric perturbations of self-adjoint operators with eigenvalues having arbitrary multiplicities, includi…

math.SP2026

Spectral projections of an anharmonic oscillator with complex polynomial potential

Boris Mityagin, Petr Siegl

For a broad class of polynomial potentials $V$ , with an important and instructive representative being $V (x) = x^{2 a} + i x^{b}$ , $x \in R$ , $a, b \in N$ , we show tha…

math.SP2025

Local form subordination without a power decay and a criterion of Riesz basesness

Boris Mityagin, Petr Siegl

We revisit the local form subordination condition on the perturbation of a self-adjoint operators with compact resolvent, which is used to show the Riesz basis property of the eige…

Eigensystems of Dirac operators with singular potentials

Estimates of I^-functions and their log-derivatives

Riesz property in the case of multiple eigenvalues

Spectral projections of an anharmonic oscillator with complex polynomial potential

Local form subordination without a power decay and a criterion of Riesz basesness

Estimates of $I^$ -functions and their $lo g$ -derivatives