Search Results - "Walther, Uli"

On Feynman graphs, matroids, and GKZ-systems by Walther, Uli

“…We show in several important cases that the A -hypergeometric system attached to a Feynman diagram in Lee–Pomeransky form, obtained by viewing the coefficients…”
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Dependence of Lyubeznik numbers of cones of projective schemes on projective embeddings by Reichelt, Thomas, Saito, Morihiko, Walther, Uli

“…We construct complex projective schemes with Lyubeznik numbers of their cones depending on the choices of projective embeddings. This answers a question of…”
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Matroid connectivity and singularities of configuration hypersurfaces by Denham, Graham, Schulze, Mathias, Walther, Uli

“…Consider a linear realization of a matroid over a field. One associates with it a configuration polynomial and a symmetric bilinear form with linear…”
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Koszul and local cohomology, and a question of Dutta by Ma, Linquan, Singh, Anurag K., Walther, Uli

“…For ( A , m ) a local ring, we study the natural map from the Koszul cohomology module H dim A ( m ; A ) to the local cohomology module H m dim A ( A ) . We…”
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Algebraic aspects of hypergeometric differential equations by Reichelt, Thomas, Schulze, Mathias, Sevenheck, Christian, Walther, Uli

“…We review some classical and modern aspects of hypergeometric differential equations, including A -hypergeometric systems of Gel ′ fand, Graev, Kapranov and…”
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On normalized Horn systems by Berkesch, Christine, Matusevich, Laura Felicia, Walther, Uli

“…We characterize the (regular) holonomicity of Horn systems of differential equations under a hypothesis that captures the most widely studied classical…”
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Singularities and holonomicity of binomial D-modules by Berkesch Zamaere, Christine, Matusevich, Laura Felicia, Walther, Uli

“…We study binomial D-modules, which generalize A-hypergeometric systems. We determine explicitly their singular loci and provide three characterizations of…”
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Homological Methods for Hypergeometric Families by Matusevich, Laura Felicia, Miller, Ezra, Walther, Uli

“…We analyze the behavior of the holonomic rank in families of holonomic systems over complex algebraic varieties by providing homological criteria for…”
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A connectedness result in positive characteristic by Singh, Anurag K., Walther, Uli

“…Let (R,\mathfrak{m}) be a complete local ring of dimension at least two, which contains a separably closed coefficient field of positive characteristic. Using…”
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Algorithmic computation of local cohomology modules and the local cohomological dimension of algebraic varieties by Walther, Uli

“…In this paper we present algorithms that compute certain local cohomology modules associated to ideals in a ring of polynomials containing the rational…”
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The Jacobian module, the Milnor fiber, and the D-module generated by $$f^s$$ f s by Walther, Uli

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The Jacobian module, the Milnor fiber, and the D-module generated by by Walther, Uli

“…(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).For a germ f on a complex manifold X, we introduce a complex derived from the…”
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The Jacobian module, the Milnor fiber, and the D-module generated by fs by Walther, Uli

“…For a germ f on a complex manifold X , we introduce a complex derived from the Liouville form acting on logarithmic differential forms, and give an exactness…”
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On the Lyubeznik numbers of a local ring by Walther, Uli

“…We collect some information about the invariants \lambda_{p,i}(A) of a commutative local ring A containing a field introduced by G. Lyubeznik in 1993…”
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Gauß-Manin systems of families of Laurent polynomials and A-hypergeometric systems by Reichelt, Thomas, Walther, Uli

“…In this note we study families of Gauß-Manin systems arising from Laurent polynomials with parametric coefficients under projection to the parameter space. For…”
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On Lyubeznik type invariants by Reichelt, Thomas, Walther, Uli, Zhang, Wenliang

“…We discuss for an affine variety Y embedded in affine space X two sets of integers attached to Y⊆X via local and de Rham cohomology spectral sequences. We…”
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Hypergeometric D-modules and twisted Gauß–Manin systems by Schulze, Mathias, Walther, Uli

“…The Euler–Koszul complex is the fundamental tool in the homological study of A-hypergeometric differential systems and functions. We compare Euler–Koszul…”
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On the b-Functions of Hypergeometric Systems by Reichelt, Thomas, Sevenheck, Christian, Walther, Uli

“…Abstract For any integer $d\times (n+1)$ matrix $A$ and parameter $\beta\in\mathbb{C}^d$ let $M_A(\beta)$ be the associated $A$-hypergeometric (or GKZ) system…”
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Irregularity of hypergeometric systems via slopes along coordinate subspaces by Schulze, Mathias, Walther, Uli

“…We study the irregularity sheaves attached to the A -hypergeometric D-module M A ( β ) introduced by I. M. Gel'fand and others in [GGZ], [GZK], where A ∈ Z d ×…”
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On a conjecture of Lynch by Singh, Anurag K., Walther, Uli

“…We comment on a conjecture of Lynch on annihilators of local cohomology. Communicated by Lawrence Ein…”
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