TY  - JOUR
A1  - Baumgärtel, Hellmut
T1  - Lax-phillips evolutions in quantum mechanics and two-space scattering
Y1  - 2004
SN  - 0034-4877
ER  - 
TY  - JOUR
A1  - Baumgärtel, Hellmut
T1  - Lax-phillips evolutions in quantum mechanics and two-space scattering
Y1  - 2004
SN  - 0034-4877
ER  - 
TY  - BOOK
A1  - Baumgärtel, Hellmut
T1  - A modified approach to the Doplicher-Roberts theorem on the construction of field algebra and the symmetry group in superselection theory
T3  - Preprint / SFB 288, Differentialgeometrie und Quantenphysik
Y1  - 1994
VL  - 134
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Baumgärtel, Hellmut
T1  - Generalized eigenvectors for resonances in the Friedrichs model and their associated Gamov vectors
N2  - A Gelfand triplet for the Hamiltonian H of the Priedrichs model on R with multiplicity space K, dim K < infinity, is constructed such that exactly the resonances (poles of the inverse of the Livsic-matrix) are (generalized) eigenvalues of H. The corresponding eigen(anti)linear forms are calculated explicitly. Using the wave matrices for the wave (Moller) operators the corresponding eigen(anti)linear forms on the Schwartz space S for the unperturbed Hamiltonian Ho are also calculated. It turns out that they are of pure Dirac type and can be characterized by their corresponding Gamov vector lambda -> k/(zeta(0)-lambda)(-1), zeta(0) resonance, k epsilon K, which is uniquely determined by restriction of S to S boolean AND H-+(2), where H-+(2) denotes the Hardy space of the upper half-plane. Simultaneously this restriction yields a truncation of the generalized evolution to the well-known decay semigroup for t >= 0 of the Toeplitz type on H-+(2). That is: Exactly those pre-Gamov vectors a lambda -> k/(zeta-lambda)(-1), ( from the lower half-plane, k epsilon K., have an extension to a generalized eigenvector of H if zeta is a resonance and if k is from that subspace of K which is uniquely determined by its corresponding Dirac type antilinear form
Y1  - 2006
UR  - http://www.worldscinet.com/rmp/rmp.shtml
U6  - https://doi.org/10.1142/S0129055X06002589
SN  - 0129-055X
ER  - 
TY  - BOOK
A1  - Baumgärtel, Hellmut
T1  - Operatoralgebraic methods in quantum field theory : a series of lectures
Y1  - 1995
PB  - Akademie Verl.
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Baumgärtel, Hellmut
T1  - Fourier transformation of Hilbert C*-systems, with compact groups, by their regular representation
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Baumgärtel, Hellmut
T1  - On Haag dual nets over compact spaces
Y1  - 1995
ER  - 
TY  - BOOK
A1  - Baumgärtel, Hellmut
T1  - Some operatoralgebraic fundamentals of the algebraic quantum field theory
T3  - Preprint / Universität Potsdam, Fachbereich Mathematik
Y1  - 1993
VL  - 1993, 09
PB  - Univ.
CY  - Potsdam
ER  - 
TY  - BOOK
A1  - Baumgärtel, Hellmut
T1  - Operatoralgebren und Quantenfeldtheorie
T3  - Preprint / Universität Potsdam, Fachbereich Mathematik
Y1  - 1993
VL  - 1993, 12
PB  - Univ.
CY  - Potsdam
ER  - 
TY  - BOOK
A1  - Baumgärtel, Hellmut
T1  - Über Superauswahlstrukturen und deren Eichgruppen
T3  - Preprint / Universität Potsdam, Institut für Mathematik
Y1  - 1997
VL  - 1997, 06
PB  - Univ.
CY  - Potsdam
ER  -