Results 1  10
of
74,254
A method for calculating vertextype Feynman integrals
, 1986
"... A method is proposed for exact calculation of the dimensionally regulated vertextype Feynman diagrams. This method is used to obtain expressions for a class of massless vertex integrals which extend the number of exactly calculable Feynman diagrams in the quantum field theory and which are of inter ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
A method is proposed for exact calculation of the dimensionally regulated vertextype Feynman diagrams. This method is used to obtain expressions for a class of massless vertex integrals which extend the number of exactly calculable Feynman diagrams in the quantum field theory and which
Vertex
"... Abstract. The structural semantics of UMLbased metamodeling were recently explored[1], providing a characterization of the models adhering to a metamodel. In particular, metamodels can be converted to a set of constraints expressed in a decidable subset of firstorder logic, an extended Horn logic. ..."
Abstract
 Add to MetaCart
Abstract. The structural semantics of UMLbased metamodeling were recently explored[1], providing a characterization of the models adhering to a metamodel. In particular, metamodels can be converted to a set of constraints expressed in a decidable subset of firstorder logic, an extended Horn logic. We augment the constructive techniques found in logic programming, which are also based on an extended Horn logic, to produce constructive techniques for reasoning about models and metamodels. These methods have a number of practical applications: At the metalevel, it can be decided if a (composite) metamodel characterizes a nonempty set of models, and a member can be automatically constructed. At the modellevel, it can be decided if a submodel has an embeddeding in a wellformed model, and the larger model can be constructed. This amounts to automatic model construction from an incomplete model. We describe the concrete algorithms for constructively solving these problems, and provide concrete examples. 1 Preliminaries Metamodels, Domains, and Logic This paper describes constructive techniques, similar to those found in logic programming, for reasoning about domainspecific modeling languages (DSMLs) defined with metamodels. Before we proceed, we must describe how a metamodel can be viewed as a formal object that characterizes the wellformed models adhering to that metamodel. We will refer to the models that adhere to metamodel X as the models of metamodel X. In order to build some intuition for
The tropical vertex
"... Abstract. Elements of the tropical vertex group are formal families of symplectomorphisms of the 2dimensional algebraic torus. We prove ordered product factorizations in the tropical vertex group are equivalent to calculations of certain genus 0 relative GromovWitten invariants of toric surfaces. ..."
Abstract

Cited by 33 (10 self)
 Add to MetaCart
Abstract. Elements of the tropical vertex group are formal families of symplectomorphisms of the 2dimensional algebraic torus. We prove ordered product factorizations in the tropical vertex group are equivalent to calculations of certain genus 0 relative GromovWitten invariants of toric surfaces
A lecture on the Liouville vertex operators
 Int. J. Mod. Phys. A
, 2004
"... We reconsider the construction of exponential fields in the quantized Liouville theory. It is based on a freefield construction of a continuous family or chiral vertex operators. We derive the fusion and braid relations of the chiral vertex operators. This allows us to simplify the verification of ..."
Abstract

Cited by 53 (12 self)
 Add to MetaCart
We reconsider the construction of exponential fields in the quantized Liouville theory. It is based on a freefield construction of a continuous family or chiral vertex operators. We derive the fusion and braid relations of the chiral vertex operators. This allows us to simplify the verification
Vertex algebras and mirror symmetry
 557. MR 2002f:17046
"... Mirror Symmetry for CalabiYau hypersurfaces in toric varieties is by now well established. However, previous approaches to it did not uncover the underlying reason for mirror varieties to be mirror. We are able to calculate explicitly vertex algebras that correspond to holomorphic parts of A and B ..."
Abstract

Cited by 30 (5 self)
 Add to MetaCart
Mirror Symmetry for CalabiYau hypersurfaces in toric varieties is by now well established. However, previous approaches to it did not uncover the underlying reason for mirror varieties to be mirror. We are able to calculate explicitly vertex algebras that correspond to holomorphic parts of A and B
Improving the performance of the vertex elimination algorithm for derivative calculation
 in AD2004: Proceedings of the 4th International Conference on Automatic Differentiation
, 2005
"... heuristics aiming to find elimination sequences that minimise the number of floatingpoint operations (flops) for vertex elimination Jacobian code. We also used the depthfirst traversal algorithm to reorder the statements of the Jacobian code with the aim of reducing the number of memory accesses. ..."
Abstract

Cited by 2 (1 self)
 Add to MetaCart
. In this work, we study the effects of reducing flops or memory accesses within the vertex elimination algorithm for Jacobian calculation. On RISC processors, we observed that for data residing in registers, the number of flops gives a good estimate of the execution time, while for outofregister data
TWOLOOP CALCULATIONS WITH VERTEX CORRECTIONS IN THE WALECKA MODEL
, 1994
"... Twoloop corrections with scalar and vector form factors are calculated for nuclear matter in the Walecka model. The onshell form factors are derived from vertex corrections within the framework of the model and are highly damped at large spacelike momenta. The twoloop corrections are evaluated fi ..."
Abstract
 Add to MetaCart
Twoloop corrections with scalar and vector form factors are calculated for nuclear matter in the Walecka model. The onshell form factors are derived from vertex corrections within the framework of the model and are highly damped at large spacelike momenta. The twoloop corrections are evaluated
Improving the Performance of the Vertex Elimination Algorithm for Derivative Calculation
"... We study two aspects of the vertex elimination algorithm in calculating Jacobians. First, we used Markowitzlike heuristics aiming at minimising the number of floatingpoint operations to find elimination sequences and then generate the Jacobian code. Second, we used the depthfirst traversal algorit ..."
Abstract
 Add to MetaCart
We study two aspects of the vertex elimination algorithm in calculating Jacobians. First, we used Markowitzlike heuristics aiming at minimising the number of floatingpoint operations to find elimination sequences and then generate the Jacobian code. Second, we used the depthfirst traversal
Results 1  10
of
74,254