J. Adduci

most citedConvergence Radii for Eigenvalues of Tri--diagonal Matrices

4 citations · 4 across the 3 of their papers we have counts for

collaborators

3 papers

math.SP2011

Root System of a Perturbation of a Selfadjoint Operator with Discrete Spectrum

James Adduci, Boris Mityagin

We analyze the perturbations $T + B$ of a selfadjoint operator $T$ in a Hilbert space $H$ with discrete spectrum ${t_{k}}$ , $T ϕ_{k} = t_{k} ϕ_{k}$ , as an extension of our constructions i…

math.SP2009

Eigensystem of an $L^{2}$ -perturbed harmonic oscillator is an unconditional basis

James Adduci, Boris Mityagin

We prove the following. For any complex valued $L^{p}$ -function $b (x)$ , $2 \leq p < \infty$ or $L^{\infty}$ -function with the norm $∥ b ∣ L^{\infty} ∥ < 1$ , the spectrum of a perturbe…

math.SP2009★ 4 cited

Convergence Radii for Eigenvalues of Tri--diagonal Matrices

J. Adduci, P. Djakov, B. Mityagin

Consider a family of infinite tri--diagonal matrices of the form $L + z B,$ where the matrix $L$ is diagonal with entries $L_{k k} = k^{2},$ and the matrix $B$ is off--diagonal, with non…

Root System of a Perturbation of a Selfadjoint Operator with Discrete Spectrum

Eigensystem of an L2-perturbed harmonic oscillator is an unconditional basis

Convergence Radii for Eigenvalues of Tri--diagonal Matrices

Eigensystem of an $L^{2}$ -perturbed harmonic oscillator is an unconditional basis