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Operators of the q-oscillator

Franciszek Hugon Szafraniec (2007)

Banach Center Publications

We scrutinize the possibility of extending the result of [19] to the case of q-deformed oscillator for q real; for this we exploit the whole range of the deformation parameter as much as possible. We split the case into two depending on whether a solution of the commutation relation is bounded or not. Our leitmotif is subnormality. The deformation parameter q is reshaped and this is what makes our approach effective. The newly arrived parameter, the operator C, has two remarkable properties: it...

Optimal Holomorphic Hypercontractivity for CAR Algebras

Ilona Królak (2010)

Bulletin of the Polish Academy of Sciences. Mathematics

We present a new proof of Janson’s strong hypercontractivity inequality for the Ornstein-Uhlenbeck semigroup in holomorphic algebras associated with CAR (canonical anticommutation relations) algebras. In the one generator case we calculate optimal bounds for t such that U t is a contraction as a map L ( ) L p ( ) for arbitrary p ≥ 2. We also prove a logarithmic Sobolev inequality.

Positive energy quantization of linear dynamics

Jan Dereziński, Christian Gérard (2010)

Banach Center Publications

The abstract mathematical structure behind the positive energy quantization of linear classical systems is described. It is separated into three stages: the description of a classical system, the algebraic quantization and the Hilbert space quantization. Four kinds of systems are distinguished: neutral bosonic, neutral bosonic, charged bosonic and charged fermionic. The formalism that is described follows closely the usual constructions employed in quantum physics to introduce noninteracting quantum...

Remarks on q-CCR relations for |q| > 1

Marek Bożejko (2007)

Banach Center Publications

In this paper we give a construction of operators satisfying q-CCR relations for q > 1: A ( f ) A * ( g ) - A * ( g ) A ( f ) = q N f , g I and also q-CAR relations for q < -1: B ( f ) B * ( g ) + B * ( g ) B ( f ) = | q | N f , g I , where N is the number operator on a suitable Fock space q ( ) acting as Nx₁ ⊗ ⋯ ⊗ xₙ = nx₁ ⊗ ⋯ ⊗xₙ. Some applications to combinatorial problems are also given.

Supersymmetry and Ghosts in Quantum Mechanics

Robert, Didier (2008)

Serdica Mathematical Journal

2000 Mathematics Subject Classification: 81Q60, 35Q40.A standard supersymmetric quantum system is defined by a Hamiltonian [^H] = ½([^Q]*[^Q] +[^Q][^Q]*), where the super-charge [^Q] satisfies [^Q]2 = 0, [^Q] commutes with [^H]. So we have [^H] ≥ 0 and the quantum spectrum of [^H] is non negative. On the other hand Pais-Ulhenbeck proposed in 1950 a model in quantum-field theory where the d'Alembert operator [¯] = [(∂2)/( ∂t2)] − Δx is replaced by fourth order operator [¯]([¯] + m2), in order to...

The spin-statistics relation in nonrelativistic quantum mechanics and projective modules

Nikolaos A. Papadopoulos, Mario Paschke, Andrés Reyes, Florian Scheck (2004)

Annales mathématiques Blaise Pascal

In this work we consider non-relativistic quantum mechanics, obtained from a classical configuration space 𝒬 of indistinguishable particles. Following an approach proposed in [8], wave functions are regarded as elements of suitable projective modules over C ( 𝒬 ) . We take furthermore into account the G -Theory point of view (cf. [HPRS,S]) where the role of group action is particularly emphasized. As an example illustrating the method, the case of two particles is worked out in detail. Previous works (cf....

Truncated Infinitesimal Shifts, Spectral Operators and Quantized Universality of the Riemann Zeta Function

Hafedh Herichi, Michel L. Lapidus (2014)

Annales de la faculté des sciences de Toulouse Mathématiques

We survey some of the universality properties of the Riemann zeta function ζ ( s ) and then explain how to obtain a natural quantization of Voronin’s universality theorem (and of its various extensions). Our work builds on the theory of complex fractal dimensions for fractal strings developed by the second author and M. van Frankenhuijsen in [60]. It also makes an essential use of the functional analytic framework developed by the authors in [25] for rigorously studying the spectral operator 𝔞 (mapping...

Two-parameter non-commutative Central Limit Theorem

Natasha Blitvić (2014)

Annales de l'I.H.P. Probabilités et statistiques

In 1992, Speicher showed the fundamental fact that the probability measures playing the role of the classical Gaussian in the various non-commutative probability theories (viz. fermionic probability, Voiculescu’s free probability, and q -deformed probability of Bożejko and Speicher) all arise as the limits in a generalized Central Limit Theorem. The latter concerns sequences of non-commutative random variables (elements of a * -algebra equipped with a state) drawn from an ensemble of pair-wise commuting...

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