150 citations · 355 across the 12 of their papers we have counts for
10 papers · 1 filter
Convergent Quantum Normal Forms, -symmetry and reality of the spectrum
Emanuela Caliceti, Sandro Graffi
A class of non-selfadjoint, $\PT$-symmetric operators is identified similar to a self-adjoint one, thus entailing the reality of the spectrum. The similarity transformation is expl…
Quadratic PT-symmetric operators with real spectrum and similarity to self-adjoint operators
Emanuela Caliceti, Sandro Graffi, Michael Hitrik +1
It is established that a PT-symmetric elliptic quadratic differential operator with real spectrum is similar to a self-adjoint operator precisely when the associated fundamental ma…
A criterion for the reality of the spectrum of PT symmetric Schroedinger operators with complex-valued periodic potentials
E. Caliceti, S. Graffi
Consider in the \Sc operator family depending on the real parameter , where is a complex-valued but symmetric periodic potential. A…
Perturbation theory of PT-symmetric Hamiltonians
E. Caliceti, F. Cannata, S. Graffi
In the framework of perturbation theory the reality of the perturbed eigenvalues of a class of $\PT$symmetric Hamiltonians is proved using stability techniques. We apply this metho…
Spectral theory and distributional Borel summability for the quantum Hénon-Heiles model
Emanuela Caliceti
The Borel summability in the distributional sense is established of the divergent perturbation theory for the ground state resonance of the quantum Hénon-Heiles model.
Spectra of PT-Symmetric Operators and Perturbation Theory
Emanuela Caliceti, Sandro Graffi, Johannes Sjoestrand
Criteria are formulated both for the existence and for the non-existence of complex eigenvalues for a class of non self-adjoint operators in Hilbert space invarariant under a parti…