45 citations · 402 across the 46 of their papers we have counts for
11 papers · 1 filter
On CY-LG correspondence for (0,2) toric models
Lev A. Borisov, Ralph M. Kaufmann
We conjecture a description of the vertex (chiral) algebras of the (0,2) nonlinear sigma models on smooth quintic threefolds. We provide evidence in favor of the conjecture by conn…
The Drinfel'd Double and Twisting in Stringy Orbifold Theory
Ralph M. Kaufmann, David Pham
This paper exposes the fundamental role that the Drinfel'd double $\dkg$ of the group ring of a finite group and its twists $\dbkg$, $β\in Z^3(G,\uk)$ as defined by Dijkgraaf--…
A Note on the Two Approaches to Stringy Functors for Orbifolds
Ralph M. Kaufmann
In this note, we reconcile two approaches that have been used to construct stringy multiplications. The pushing forward after pulling back that has been used to give a global strin…
Discrete torsion, symmetric products and the Hilbert scheme
Ralph M. Kaufmann
We combine our results on symmetric products and second quantization with our description of discrete torsion in order to explain the ring structure of the cohomology of the Hilber…
Stringy K-theory and the Chern character
Tyler J. Jarvis, Ralph Kaufmann, Takashi Kimura
For a finite group G acting on a smooth projective variety X, we construct two new G-equivariant rings: first the stringy K-theory of X, and second the stringy cohomology of X. For…
Singularities with Symmetries, orbifold Frobenius algebras and Mirror Symmetry
Ralph M. Kaufmann
Previously, we introduced a duality transformation for Euler --Frobenius algebras. Using this transformation, we prove that the simple singularities and Pham singulariti…
Pointed Admissible G-Covers and G-equivariant Cohomological Field Theories
Tyler J. Jarvis, Ralph Kaufmann, Takashi Kimura
For any finite group G we define the moduli space of pointed admissible G-covers and the concept of a G-equivariant cohomological field theory (G-CohFT), which, when G is the trivi…
The algebra of discrete torsion
Ralph M. Kaufmann
We analyze the algebraic structures of G--Frobenius algebras which are the algebras associated to global group quotient objects. Here G is any finite group. These algebras turn out…
Second quantized Frobenius algebras
Ralph M. Kaufmann
We show that given a Frobenius algebra there is a unique notion of its second quantization, which is the sum over all symmetric group quotients of n--th tensor powers, where the qu…
Orbifolding Frobenius Algebras
Ralph M. Kaufmann
We study the general theory of Frobenius algebras with group actions. These structures arise when one is studying the algebraic structures associated to a geometry stemming from a…
The tensor product in the theory of Frobenius manifolds
Ralph M. Kaufmann
We introduce the operation of forming the tensor product in the theory of analytic Frobenius manifolds. Building on the results for formal Frobenius manifolds which we extend to th…