19 citations · 62 across the 20 of their papers we have counts for
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Gaussian elements in CCR algebras
Shigeru Yamagami
A system of matrix units in the Weyl algebra of convolution type is constructed with the aid of a Gaussian element so that it includes von Neumann's minimal projection, which expli…
Scaling Flow on Covariance Forms of CCR Algebras
Shigeru Yamagami
In connection with parametric rescaling of free dynamics of CCR, we introduce a flow on the set of covariance forms and investigate its thermodynamic behavior at low temperature wi…
Kakutani Dichotomy on Free States
Taku Matsui, Shigeru Yamagami
Two quasi-free states on a CAR or CCR algebra are shown to generate quasi-equivalent representations unless they are disjoint.
Geometry of Coherent States of CCR Algebras
Shigeru Yamagami
Geometric positions of square roots of coherent states of CCR algebras are investigated along with an explicit formula for transition amplitudes among them, which is a natural exte…
Geometry of Quasi-Free States of CCR Algebras
Shigeru Yamagami
Geometric positions of square roots of quasi-free states of CCR algebras are investigated together with an explicit formula for transition amplitudes among them.
Geometric Mean of States and Transition Amplitudes
Shigeru Yamagami
The transition amplitude between square roots of states, which is an analogue of Hellinger integral in classical measure theory, is investigated in connection with operator-algebra…