943 citations · 1.2k across the 6 of their papers we have counts for
6 papers
The Naimark dilated PT-symmetric brachistochrone
Uwe Guenther, Boris F. Samsonov
The quantum mechanical brachistochrone system with PT-symmetric Hamiltonian is Naimark dilated and reinterpreted as subsystem of a Hermitian system in a higher-dimensional Hilbert…
Determining role of Krein signature for 3D Arnold tongues of oscillatory dynamos
Oleg N. Kirillov, Uwe Guenther, Frank Stefani
Using a homotopic family of boundary eigenvalue problems for the mean-field -dynamo with helical turbulence parameter and homotopy parameter , we…
Visualization of Branch Points in PT-Symmetric Waveguides
Shachar Klaiman, Nimrod Moiseyev, Uwe Gunther
The visualization of an exceptional point in a PT symmetric directional coupler(DC) is demonstrated. In such a system the exceptional point can be probed by varying only a single p…
The MHD alpha^2-dynamo, Z_2-graded pseudo-Hermiticity, level crossings and exceptional points of branching type
U. Guenther, F. Stefani, G. Gerbeth
The spectral branching behavior of the 2x2 operator matrix of the magneto-hydrodynamic alpha^2-dynamo is analyzed numerically. Some qualitative aspects of level crossings are brief…
Inverse Problems in Magnetohydrodynamics: Theoretical and Experimental Aspects
Frank Stefani, Thomas Gundrum, Gunter Gerbeth +2
We consider inverse problems related to the velocity reconstruction in electrically conducting fluids from externally measured magnetic fields. The underlying theory is presented i…
Gravitational excitons from extra dimensions
U. Guenther, A. Zhuk
We study inhomogeneous multidimensional cosmological models with a higher dimensional space-time manifold under dimensional reduction and show that small inhomogeneous excitations…