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1.
The 2-dimensional BF theory is both a gauge theory and a topological Poisson σ-model corresponding to a linear Poisson bracket. In [3], Torossian discovered a connection which governs correlation functions of the BF theory with sources for the B-field. This connection is flat, and it is a close relative of the KZ connection in the WZW model. In this Letter, we show that flatness of the Torossian connection follows from (properly regularized) quantum equations of motion of the BF theory. 相似文献
2.
We introduce left central and right central functions and left and right leaves in quasi-Poisson geometry, generalizing central (or Casimir) functions and symplectic leaves from Poisson geometry. They lead to a new type of (quasi-)Poisson reduction, which is both simpler and more general than known quasi-Hamiltonian reductions. We study these notions in detail for moduli spaces of flat connections on surfaces, where the quasi-Poisson structure is given by an intersection pairing on homology. 相似文献
3.
Adjoint triples and pairs are basic operators used in several domains, since they increase the flexibility in the framework in which they are considered. This paper introduces multi-adjoint algebras and several properties; also, we will show that an adjoint triple and its “dual” cannot be considered in the same framework.Moreover, a comparison among general algebraic structures used in different frameworks, which reduce the considered mathematical requirements, such as the implicative extended-order algebras, implicative structures, the residuated algebras given by sup-preserving aggregations and the conjunctive algebras given by semi-uninorms and u-norms, is presented. This comparison shows that multi-adjoint algebras generalize these structures in domains which require residuated implications, such as in formal concept analysis, fuzzy rough sets, fuzzy relation equations and fuzzy logic. 相似文献
4.
T. Rapcsák 《Journal of Optimization Theory and Applications》2005,127(1):165-176
Some properties of the spaces of paths are studied in order to define and characterize the local convexity of sets belonging
to smooth manifolds and the local convexity of functions defined on local convex sets of smooth manifolds.
This paper is dedicated to the memory of Guido Stampacchia. This research was supported in part by the Hungarian Scientific
Research Fund, Grants OTKA-T043276 and OTKA-T043241, and by CNR, Rome, Italy. 相似文献
5.
George N. Galanis 《Periodica Mathematica Hungarica》2007,54(1):1-13
A new methodology leading to the construction of a universal connection for Fréchet principal bundles is proposed in this
paper. The classical theory, applied successfully so far for finite dimensional and Banach modelled bundles, collapses within
the framework of Fréchet manifolds. However, based on the replacement of the space of continuous linear mappings by an appropriate
topological vector space, we endow the bundle J
1
P of 1-jets of the sections of a Fréchet principal bundle P with a connection form by means of which we may “reproduce” every connection of P.
相似文献
6.
It is shown that, up to a diffeomorphism, the linearized Poisson structure does not depend on the choice of the transversal near the zero section. 相似文献
7.
Barbara Opozda 《Geometriae Dedicata》1998,69(1):1-14
We propose to study n-dimensional purely real submanifolds of the standard affine complex space Cn from an affine point of view. Such submanifolds are naturally endowed with a unique transversal bundle. Fundamental theorems are given as well as a theorem of Cartan–Norden type. Examples illustrating particular affine properties of such submanifolds are provided. 相似文献
8.
9.
We elaborate on nonassociative differential geometry of phase spaces endowed with nonholonomic (non-integrable) distributions and frames, nonlinear and linear connections, symmetric and nonsymmetric metrics, and correspondingly adapted quasi-Hopf algebra structures. The approach is based on the concept of nonassociative star product introduced for describing closed strings moving in a constant R-flux background. Generalized Moyal-Weyl deformations are considered when, for nonassociative and noncommutative terms of star deformations, there are used nonholonomic frames (bases) instead of local partial derivatives. In such modified nonassociative and nonholonomic spacetimes and associated complex/real phase spaces, the coefficients of geometric and physical objects depend both on base spacetime coordinates and conventional (co) fiber velocity/momentum variables like in (non) commutative Finsler-Lagrange-Hamilton geometry. For nonassociative and (non) commutative phase spaces modelled as total spaces of (co) tangent bundles on Lorentz manifolds enabled with star products and nonholonomic frames, we consider associated nonlinear connection, N-connection, structures determining conventional horizontal and (co) vertical (for instance, 4+4) splitting of dimensions and N-adapted decompositions of fundamental geometric objects. There are defined and computed in abstract geometric and N-adapted coefficient forms the torsion, curvature and Ricci tensors. We extend certain methods of nonholonomic geometry in order to construct R-flux deformations of vacuum Einstein equations for the case of N-adapted linear connections and symmetric and nonsymmetric metric structures. 相似文献
10.
Given a supervector bundle , we exhibit a parametrization of Quillen superconnections on by graded connections on the Cartan–Koszul supermanifold . The relation between the curvatures of both kind of connections, and their associated Chern classes, is discussed in detail. In particular, we find that Chern classes for graded vector bundles on split supermanifolds can be computed through the associated Quillen superconnections. 相似文献