English

Shifted Schur Functions

q-alg 2008-02-03 v1 Quantum Algebra

Abstract

The classical algebra Λ\Lambda of symmetric functions has a remarkable deformation Λ\Lambda^*, which we call the algebra of shifted symmetric functions. In the latter algebra, there is a distinguished basis formed by shifted Schur functions sμs^*_\mu, where μ\mu ranges over the set of all partitions. The main significance of the shifted Schur functions is that they determine a natural basis in Z(gl(n))Z(\frak{gl}(n)), the center of the universal enveloping algebra U(gl(n))U(\frak{gl}(n)), n=1,2,n=1,2,\ldots. The functions sμs^*_\mu are closely related to the factorial Schur functions introduced by Biedenharn and Louck and further studied by Macdonald and other authors. A part of our results about the functions sμs^*_\mu has natural classical analogues (combinatorial presentation, generating series, Jacobi--Trudi identity, Pieri formula). Other results are of different nature (connection with the binomial formula for characters of GL(n)GL(n), an explicit expression for the dimension of skew shapes λ/μ\lambda/\mu, Capelli--type identities, a characterization of the functions sμs^*_\mu by their vanishing properties, `coherence property', special symmetrization map S(gl(n))U(gl(n))S(\frak{gl}(n))\to U(\frak{gl}(n)). The main application that we have in mind is the asymptotic character theory for the unitary groups U(n)U(n) and symmetric groups S(n)S(n) as nn\to\infty. The results of this paper were used in \cite{Ok1--3}.

Keywords

Cite

@article{arxiv.q-alg/9605042,
  title  = {Shifted Schur Functions},
  author = {Andrei Okounkov and Grigori Olshanski},
  journal= {arXiv preprint arXiv:q-alg/9605042},
  year   = {2008}
}

Comments

65 pages, AMS-TeX