Now showing items 1-12 of 12

• #### A categorical model for the virtual braid group ﻿

[OWP-2011-19] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-18)
• #### Combinatorics of Vassiliev invariants ﻿

[OWP-2011-22] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-20)
This paper is an introductory survey of the combinatorial aspects of the Vassiliev theory of knot invariants following the lectures delivered at the Advanced School on Knot Theory and its Applications to Physics and Biology ...
• #### Commuting Differential Operators and Higher-dimensional Algebraic Varieties ﻿

[OWP-2012-02] (Mathematisches Forschungsinstitut Oberwolfach, 2012-03-20)
Several algebro-geometric properties of commutative rings of partial differential operators as well as several geometric constructions are investigated.
• #### Cryptanalysis of Public-key Cryptosystems Based on Algebraic Geometry Codes ﻿

[OWP-2012-01] (Mathematisches Forschungsinstitut Oberwolfach, 2012-03-20)
This paper addresses the question of retrieving the triple $(\mathcal{X},\mathcal{P},\mathcal{E})$ from the algebraic geometry code $\mathcal{C}_L(\mathcal{X},\mathcal{P},\mathcal{E})$, where $\mathcal{X}$ is an algebraic ...
• #### Crystal energy functions via the charge in types A and C ﻿

[OWP-2011-25] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-23)
The Ram-Yip formula for Macdonald polynomials (at $t=0$) provides a statistic which we call charge. In types $A$ and $C$ it can be defined on tensor products of Kashiwara-Nakashima single column crystals. In this ...
• #### Localized Endomorphisms of Graph Algebras ﻿

[OWP-2011-04] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-7)
Endomorphisms of graph $C^*$-algebras are investigated. A combinatorial approach to analysis of permutative endomorphisms is developed. Then invertibility criteria for localized endomorphisms are given. Furthermore, ...
• #### A note on delta hedging in markets with jumps ﻿

[OWP-2011-23] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-21)
Modelling stock prices via jump processes is common in financial markets. In practice, to hedge a contingent claim one typically uses the so-called delta-hedging strategy. This strategy stems from the Black–Merton–Scholes ...
• #### On Canonical Forms for Two-person Zero-sum Limit Average Payoff Stochastic Games ﻿

[OWP-2011-35] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-29)
We consider two-person zero-sum mean payoff undiscounted stochastic games. We give a sufficient condition for the existence of a saddle point in uniformly optimal stationary strategies. Namely, we obtain sufficient ...
• #### On commuting varieties of nilradicals of borel subalgebras of reductive lie algebras ﻿

[OWP-2012-14] (Mathematisches Forschungsinstitut Oberwolfach, 2012-12-04)
Let $G$ be a connected reductive algebraic group defined over an algebraically closed field $\mathbb{k}$ of characteristic zero. We consider the commuting variety $\mathcal{C}(\mathfrak{u})$ of the nilradical $\mathfrak{u}$ ...
• #### Quotients of Index Two and General Quotients in a Space of Orderings ﻿

[OWP-2011-36] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-30)
In this paper we investigate quotient structures and quotient spaces of a space of orderings arising from subgroups of index two. We provide necessary and sufficient conditions for a quotient structure to be a quotient ...
• #### A real algebra perspective on multivariate tight wavelet frames ﻿

[OWP-2012-11] (Mathematisches Forschungsinstitut Oberwolfach, 2012-08-13)
Recent results from real algebraic geometry and the theory of polynomial optimization are related in a new framework to the existence question of multivariate tight wavelet frames whose generators have at least one vanishing ...
• #### The Weyl group of the Curtz algebra ﻿

[OWP-2011-31] (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-28)
The Weyl group of the Cuntz algebra $\mathcal{O}_n$ is investigated. This is (isomorphic to) the group of polynomial automorphisms $\lambda_u$ of $\mathcal{O}_n$, namely those induced by unitaries u that can be written ...