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    • NonHermitian Starshaped Quantum Graphs 

      Autor: Znojil , Miloslav
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      A compact review is given, and a few new numerical results are added to the recent studies of the q-pointed one-dimensional star-shaped quantum graphs. These graphs are assumed endowedwith certain specific, manifestly ...
    • Weakly Ordered ACommutative Partial Groups of Linear Operators Densely Defined on Hilbert Space 

      Autor: Janda , Jirí
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      The notion of a generalized effect algebra is presented as a generalization of effect algebra for an algebraic description of the structure of the set of all positive linear operators densely defined on a Hilbert space ...
    • Intervals in Generalized Effect Algebras and their Subgeneralized Effect Algebras 

      Autor: Riečanová , Zdenka; Zajac , Michal
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      We consider subsets G of a generalized effect algebra E with 0∈G and such that every interval [0, q]G = [0, q]E ∩ G of G (q ∈ G , q ≠ 0) is a sub-effect algebra of the effect algebra [0, q]E. We give a condition on E and ...
    • Complex Covariance 

      Autor: Kleefeld , Frieder
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      According to some generalized correspondence principle the classical limit of a non-Hermitian quantum theory describing quantum degrees of freedom is expected to be the well known classical mechanics of classical degrees ...
    • Inherited Properties of Effect Algebras Preserved by Isomorphisms 

      Autor: Paseka , Jan; Riečanová , Zdenka
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      We show that isomorphism of effect algebras preserves properties of effect algebras derived from effect algebraic sum ? of elements. These are partial order, order convergence, order topology, existence of states and other ...
    • Generalized Continuity Equation for QuasiHermitian Hamiltonians 

      Autor: Hammou , Amine B.
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      The continuity relation is generalized to quasi-Hermitian one-dimensional Hamiltonians. As an application we show that the reflection and transmission coefficients computed with the generalized current obey the conventional ...
    • On the Solvability of Some Partial Differential Inequality 

      Autor: Himmel , Martin
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      The Dulac criterion is a classical method for ruling out the existence of periodic solutions in planar differential equations. In this paper the applicability and therefore reversibility of this criterionis under consideration.
    • Emmy Noether and Linear Evolution Equations 

      Autor: Leach , P. G. L.
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      Noether’s Theorem relates the Action Integral of a Lagrangian with symmetries which leave it invariant and the first integrals consequent upon the variational principle and the existence of the symmetries. These each have ...
    • Spectral Singularities do not Correspond to Bound States in the Continuum 

      Autor: Mostafazadeh , Ali
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      We show that, contrary to a claim made in arXiv:1011.0645, the von Neumann-Winger bound states that lie in the continuum of the scattering states are fundamentally different from Naimark’s spectral singularities.
    • Stationary and Dynamical Solutions of the GrossPitaevskii Equation for a BoseEinstein Condensate in a PT symmetric Double Well 

      Autor: Cartarius , Holger; Dast , Dennis; Haag , Daniel; Wunner , Günter; Eichler , Rüdiger; Main , Jorg
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      We investigate the Gross-Pitaevskii equation for a Bose-Einstein condensate in a PT symmetric double-well potential by means of the time-dependent variational principle and numerically exact solutions. A one-dimensional ...
    • Spectral Analysis of Schrödinger Operators with Unusual Semiclassical Behavior 

      Autor: Exner , Pavel; Barseghyan , Diana
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      In this paper we discuss several examples of Schrödinger operators describing a particle confined to a region with thin cusp-shaped ‘channels’, given either by a potential or by a Dirichlet boundary; we focus on cases when ...
    • The Twodimensional Harmonic Oscillator on a Noncommutative Space with Minimal Uncertainties 

      Autor: Dey , Sanjib; Fring , Andreas
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2013)
      The two dimensional set of canonical relations giving rise to minimal uncertainties previously constructed from a q-deformed oscillator algebra is further investigated. We provide a representation for this algebra in terms ...