Victor Nistor

  1. The $K$-groups and the index theory of certain comparison $C^*$-algebras.

    Authors: Victor Nistor, Bertrand Monthubert
    Subjects: K-Theory and Homology
    Abstract

    We compute the $K$-theory of comparison $C^*$-algebra associated to a
    manifold with corners. These comparison algebras are an example of the abstract
    pseudodifferential algebras introduced by Connes and Moscovici \cite{M3}. Our
    calculation is obtained by showing that the comparison algebras are a
    homomorphic image of a groupoid $C^*$-algebra. We then prove an index theorem
    with values in the $K$-theory groups of the comparison algebra.

  2. Closed form asymptotics for local volatility models.

    Authors: Nick Costanzino, Victor Nistor, Wen Cheng, John Liechty, Anna Mazzucato
    Subjects: Pricing of Securities
    Abstract

    We obtain new closed-form pricing formulas for contingent claims when the
    asset follows a Dupire-type local volatility model. To obtain the formulas we
    use the Dyson-Taylor commutator method re- cently developed in [7, 8, 10] for
    short time asymptotic expansions of heat kernels, and obtain a family of
    general explicit closed form approx- imate solutions for both the pricing
    kernel and derivative price. We also perform analytic as well as a numerical
    error analysis, and compare our results to other known methods.

  3. Approximate Solutions to Second Order Parabolic Equations I: analytic estimates.

    Authors: Radu Constantinescu, Nick Costanzino, Anna L Mazzucato, Victor Nistor
    Subjects: Analysis of PDEs
    Abstract

    We establish a new type of local asymptotic formula for the Green's function
    of a parabolic linear operator with non-constant coefficients. Our procedure
    leads to an elementary, algorithmic construction of approximate solutions to
    parabolic equations which are accurate to arbitrary prescribed order in the
    short-time limit.

RSS-материал