A canonical random variable for the
q-deformed moments-cumulants formula (Trends in Infinite Dimensional Analysis and Quantum Probability)
A canonical random variable for the
q-deformed moments-cumulants formula (Trends in Infinite Dimensional Analysis and Quantum Probability)
Graphical representations of the
q-creation and the
q-annihilation operators and set partition statistics (Infinite Dimensional Analysis and Quantum Probability Theory)
In this note, we introduce acertain graphical representations of the
q-creation the
q-annihilation, the
q-numb er, and the scalar operators on the
q-Fock space.These are given as the cards on which some flow lines are drawn and increasing and decreasing of the number of lines correspond to creation and annihilation, respectively.By the cards arrangement technique with these cards, of which machinery is the same as of the partition function for the lattice spins model in statistical me- chanics, we write the moments of the
q-Poisson random variable using the number of arc crossings, which is the same set partition statistic as restricted crossings investigated by P. Biane.This result suggests another
q-deformed moments-cumulants relations, which interpolates between the usual and the free cases exactly.This is the joint work with Naoko Saitoh at Ochanomizu University.1The
q -Fock space For aHibert space 7{ and
q∈(−1,1) , the
q-Fock space
Fq(H) can be defined as follows: (see, for instance, [BS1], [BKS]) Let
Ffin(H) be the linear span of vectors of the form
ξ1⊗⋯⊗ξn∈H⊗n , where
n varies in
z≥0 and we put
H⊗0≅CΩ for some distinguished vector
Ω called vacuum.We consider the sesquilinear form
⟨⋅∣⋅⟩q on
FJjn(H) given by the sesquilinear extension of
⟨ξ1⊗⋯⊗ξn∣η1⊗⋯⊗ηm⟩q=δn,m∑π∈Snqi(π)⟨ξ1∣ηπ(1)⟩⋯⟨ξn∣ηπ(n)⟩ ,
The [Formula: see text]-bit is the [Formula: see text]-deformation of the [Formula: see text]-bit. It arises canonically from the quantum decomposition of Bernoulli random variables and the [Formula: see text]-parameter has a natural probabilistic and physical interpretation as asymmetry index of the given random variable. The connection between a new type of [Formula: see text]-deformation (generalizing the Hudson–Parthasarathy bosonization technique and different from the usual one) and the Azema martingale was established by Parthasarathy. Inspired by this result, Schürmann first introduced left and right [Formula: see text]-JW-embeddings of [Formula: see text] ([Formula: see text] complex matrices) into the infinite tensor product [Formula: see text], proved central limit theorems (CLT) based on these embeddings in the context of ∗-bi-algebras and constructed a general theory of [Formula: see text]-Levy processes on ∗-bi-algebras. For [Formula: see text], left [Formula: see text]-JW-embeddings define the Jordan–Wigner transformation, used to construct a tensor representation of the Fermi anti-commutation relations (bosonization). For [Formula: see text], they reduce to the usual tensor embeddings that were at the basis of the first quantum CLT due to von Waldenfels. The present paper is the first of a series of four in which we study these theorems in the tensor product context. We prove convergence of the CLT for all [Formula: see text]. The moments of the limit random variable coincide with those found by Parthasarathy in the case [Formula: see text]. We prove that the space where the limit random variable is represented is not the Boson Fock space, as in Parthasarathy, but the monotone Fock space in the case [Formula: see text] and a non-trivial deformation of it for [Formula: see text]. The main analytical tool in the proof is a non-trivial extension of a recently proved multi-dimensional, higher order Cesaro-type theorem. The present paper deals with the standard CLT, i.e. the limit is a single random variable. Paper1 deals with the functional extension of this CLT, leading to a process. In paper2 the left [Formula: see text]-JW–embeddings are replaced by symmetric [Formula: see text]-embeddings. The radical differences between the results of the present paper and those of2 raise the problem to characterize those CLT for which the limit space provides the canonical decomposition of all the underlying classical random variables (see the Introduction, Lemma 4.5 and Sec. 5 of the present paper for the origin of this problem). This problem is solved in the paper3 for CLT associated to states satisfying a generalized Fock property. The states considered in this series have this property.