English
Related papers

Related papers: Geometry of the Pfaff lattices

200 papers

In contrast to SPD matrices, few tools exist to perform Riemannian statistics on the open elliptope of full-rank correlation matrices. The quotient-affine metric was recently built as the quotient of the affine-invariant metric by the…

Differential Geometry · Mathematics 2022-01-19 Yann Thanwerdas , Xavier Pennec

Let G be a complex semisimple Lie group, K a maximal compact subgroup and V an irreducible representation of K. Denote by M the unique closed orbit of G in P(V) and by O its image via the moment map. For any measure on M we construct a map…

Differential Geometry · Mathematics 2010-12-10 Leonardo Biliotti , Alessandro Ghigi

We study the perfect matching lattice of a matching covered graph $G$, generated by the incidence vectors of its perfect matchings. Building on results of Lov\'asz and de Carvalho, Lucchesi, and Murty, we give a polynomial-time algorithm…

Combinatorics · Mathematics 2025-11-07 Olha Silina

This paper is devoted to the complete classification of space curves under affine transformations in the view of Cartan's theorem. Spivak has introduced the method but has not found the invariants. Furthermore, for the first time, we…

Differential Geometry · Mathematics 2012-01-11 Mehdi Nadjafikhah , Ali Mahdipour Shirayeh

We study the linear Pfaffian systems satisfied by a certain class of hypergeometric functions, which includes Gau\ss's ${}_2 F_{1}$, Thomae's ${}_L F_{L-1}$ and Appell-Lauricella's $F_D$. In particular, we present a fundamental system of…

Classical Analysis and ODEs · Mathematics 2014-08-05 Teruhisa Tsuda

We introduce a linear-time algorithm for computing the Frobenius normal form (FNF) of symmetric Toeplitz matrices by utilizing their inherent structural properties through a graph-theoretic approach. Previous results of the authors…

Combinatorics · Mathematics 2025-05-28 Hojin Chu , Homoon Ryu

Lattice Boltzmann models are briefly introduced together with references to methods used to predict their ability for simulations of systems described by partial differential equations that are first order in time and low order in space…

Numerical Analysis · Mathematics 2024-11-15 Pierre Lallemand , François Dubois , Li-shi Luo

Grothendieck duality theory assigns to essentially-finite-type maps f of noetherian schemes a pseudofunctor f^\times right-adjoint to Rf_*, and a pseudofunctor f^! agreeing with f^\times when f is proper, but equal to the usual inverse…

Algebraic Geometry · Mathematics 2019-02-20 Srikanth B. Iyengar , Joseph Lipman , Amnon Neeman

For a system of ordinary differential equations (ODEs) or, more generally, an involutive distribution of vector fields, the problem of its integration is considered. Among the many approaches to this problem, solvable structures provide a…

Classical Analysis and ODEs · Mathematics 2023-08-29 A. J. Pan-Collantes , C. Muriel , A. Ruiz , J. L. Romero

Orthogonal and symplectic matrix integrals are investigated. It is shown that the matrix integrals can be considered as a $\tau$-function of the coupled KP hierarchy, whose solution can be expressed in terms of pfaffians.

solv-int · Physics 2009-10-31 Saburo Kakei

Given a generically \'etale morphism $f\colon Y\to X$ of quasi-smooth Berkovich curves, we define a different function $\delta_f\colon Y\to[0,1]$ that measures the wildness of the topological ramification locus of $f$. This provides a new…

Algebraic Geometry · Mathematics 2016-09-01 Adina Cohen , Michael Temkin , Dmitri Trushin

We consider integrable models, or in general any model defined by an $R$-matrix, on random surfaces, which are discretized using random Manhattan lattices. The set of random Manhattan lattices is defined as the set dual to the lattice…

High Energy Physics - Theory · Physics 2013-07-22 J. Ambjorn , A. Sedrakyan

We introduce a geometric approach to the construction of moment maps in finite and infinite-dimensional complex geometry. We apply this to two settings: K\"ahler manifolds and holomorphic vector bundles. Our new approach exploits the…

Differential Geometry · Mathematics 2026-02-05 Ruadhaí Dervan , Michael Hallam

We study maps from a 2D world-sheet to a 2D target space which include folds. The geometry of folds is discussed and a metric on the space of folded maps is written down. We show that the latter is not invariant under area preserving…

High Energy Physics - Theory · Physics 2019-08-15 O. Ganor , J. Sonnenschein , S. Yankielowicz

We define, within the Schroedinger functional scheme (SF), the matrix elements of the twist-2 operators corresponding to the first two moments of non-singlet parton densities. We perform a lattice one-loop calculation that fixes the…

High Energy Physics - Lattice · Physics 2009-10-31 A. Bucarelli , F. Palombi , R. Petronzio , A. Shindler

An extension of the notion of solvable structure for involutive distributions of vector fields is introduced. The new structures are based on a generalization of the concept of symmetry of a distribution of vector fields, inspired in the…

Exactly Solvable and Integrable Systems · Physics 2023-06-21 A. J. Pan-Collantes , A. Ruiz , C. Muriel , J. L. Romero

We study the uniqueness of a vortex equation involving an entire function on the complex plane. As geometric applications, we show that there is a unique harmonic map $u:\mathbb{C}\rightarrow \mathbb{H}^2$ satisfying $\partial u\neq 0$ with…

Differential Geometry · Mathematics 2017-10-31 Qiongling Li

Starting from suitable tableaux over finite dimensional Lie algebras, we provide a scheme for producing involutive linear Pfaffian systems related to various classes of submanifolds in homogeneous spaces which constitute integrable systems.…

Differential Geometry · Mathematics 2007-12-06 Emilio Musso , Lorenzo Nicolodi

Ferrers graphs and tables of partitions are treated as vectors. Matrix operations are used for simple proofs of identities concerning partitions. Interpreting partitions as vectors gives a possibility to generalize partitions on negative…

Combinatorics · Mathematics 2007-05-23 Milan kunz

This paper surveys the role of moment maps in K\"ahler geometry. The first section discusses the Ricci form as a moment map and then moves on to moment map interpretations of the K\"ahler--Einstein condition and the scalar curvature…

Symplectic Geometry · Mathematics 2020-04-21 Oscar Garcia-Prada , Dietmar Salamon