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arXiv · 0910.0155

Denjoy-Carleman differentiable perturbation of polynomials and unbounded operators

Andreas Kriegl·Peter W. Michor·Armin Rainer
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Abstract

Let $t\mapsto A(t)$ for $t\in T$ be a $C^M$-mapping with values unbounded operators with compact resolvents and common domain of definition which are self-adjoint or normal. Here $C^M$ stands for $C^\om$ (real analytic), a quasianalytic or non-quasianalytic Denjoy-Carleman class, $C^\infty$, or a H\"older continuity class $C^{0,\al}$. The parameter domain $T$ is either $\mathbb R$ or $\mathbb R^n$ or an infinite dimensional convenient vector space. We prove and review results on $C^M$-dependence on $t$ of the eigenvalues and eigenvectors of $A(t)$.

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Andreas Kriegl, Peter W. Michor, Armin Rainer. 2009-10-01. Denjoy-Carleman differentiable perturbation of polynomials and unbounded operators. https://doi.org/10.1007/s00020-011-1900-5

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