Heinz Langer

4 ta ish

Vienna University of Technology

1. A Krein Space Approach to PT-symmetry

   Heinz Langer, Christiane Tretter

   Maqola20044 iqtibos

   ABIABI:AkademIndex/2026.other.204973

2. A new concept for block operator matrices:the quadratic numerical range

   Heinz Langer, A. Markus, V. Matsaev +1

   Maqola20013 iqtibos

   ABIABI:AkademIndex/2026.other.459937

3. The Essential Spectrum of Some Matrix Operators

   F. V. Atkinson, Heinz Langer, R. Mennicken +1

   Maqola19942 iqtibos

   ABIABI:AkademIndex/2026.other.544576

4. SPECTRAL DECOMPOSITION OF SOME NONSELFADJOINT BLOCK OPERATOR MATRICES

   Heinz Langer, Christiane Tretter

   Maqola20072 iqtibos

   ABIABI:AkademIndex/2026.other.712329