A.Varchenko

  1. Reality property of discrete Wronski map with imaginary step.

    Authors: E. Mukhin, V. Tarasov, A.Varchenko
    Subjects: Quantum Algebra
    Abstract

    For a set of quasi-exponentials with real exponents, we consider the discrete
    Wronskian (also known as Casorati determinant) with pure imaginary step 2h. We
    prove that if the coefficients of the discrete Wronskian are real and for every
    its roots the imaginary part is at most |h|, then the complex span of this set
    of quasi-exponentials has a basis consisting of quasi-exponentials with real
    coefficients. This result is a generalization of the statement of the B. and M.
    Shapiro conjecture on spaces of polynomials. The proof is based on the Bethe
    ansatz for the XXX model.

  2. Cohomology of a flag variety as a Bethe algebra.

    Authors: A.Varchenko, R.Rimanyi, V.Schechtman, V.Tarasov
    Subjects: Quantum Algebra
    Abstract

    We interpret the GL_n equivariant cohomology of a partial flag variety of
    flags of length N in \C^n as the Bethe algebra of a suitable gl_N[t] module
    associated with the tensor power (\C^N)^{\otimes n}.

  3. Bethe algebra of the gl_{N+1} Gaudin model and algebra of functions on the critical set of the master function.

    Authors: E. Mukhin, V. Tarasov, A.Varchenko
    Subjects: Quantum Algebra
    Abstract

    Consider a tensor product of finite-dimensional irreducible gl_{N+1}-modules
    and its decomposition into irreducible modules. The gl_{N+1} Gaudin model
    assigns to each multiplicity space of that decomposition a commutative (Bethe)
    algebra of linear operators acting on the multiplicity space. The Bethe ansatz
    method is a method to find eigenvectors and eigenvalues of the Bethe algebra.
    One starts with a critical point of a suitable (master) function and constructs
    an eigenvector of the Bethe algebra.

Syndicate content