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Related papers: Distinguishing the Chambers of the Moment Polytope

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Consider a Hamiltonian action of a compact Lie group on a compact symplectic manifold. A theorem of Kirwan's says that the image of the momentum mapping intersects the positive Weyl chamber in a convex polytope. I present a new proof of…

dg-ga · Mathematics 2008-02-03 Reyer Sjamaar

Consider a finite collection of affine hyperplanes in $\mathbb R^d$. The hyperplanes dissect $\mathbb R^d$ into finitely many polyhedral chambers. For a point $x\in \mathbb R^d$ and a chamber $P$ the metric projection of $x$ onto $P$ is the…

Metric Geometry · Mathematics 2020-09-02 Zakhar Kabluchko

Let $M$ be a quantizable symplectic manifold acted on by $T=(S^1)^r$ in a Hamiltonian fashion and $J$ a moment map for this action. Suppose that the set $M^{T}$ of fixed points is discrete and denote by ${\alpha}_{pj}\in{\mathbb Z}^r$ the…

Symplectic Geometry · Mathematics 2007-11-05 Andrés Viña

Given a Lie group acting on a manifold $M$ preserving a closed $n+1$-form $\omega$, the notion of homotopy moment map for this action was introduced in Callies-Fregier-Rogers-Zambon [6], in terms of $L_{\infty}$-algebra morphisms. In this…

Differential Geometry · Mathematics 2016-06-30 Yael Fregier , Camille Laurent-Gengoux , Marco Zambon

We show a homotopy decomposition of $p$-localized suspension $\Sigma M_{(p)}$ of a quasitoric manifold $M$ by constructing power maps. As an application we investigate the $p$-localized suspension of the projection $\pi$ from the…

Algebraic Topology · Mathematics 2014-12-23 Sho Hasui , Daisuke Kishimoto , Takashi Sato

Associated to any manifold equipped with a closed form of degree >1 is an `L-infinity algebra of observables' which acts as a higher/homotopy analog of the Poisson algebra of functions on a symplectic manifold. In order to study Lie group…

Differential Geometry · Mathematics 2016-08-17 Martin Callies , Yael Fregier , Christopher L. Rogers , Marco Zambon

The main purpose of this article is to extend some of the ideas from Schubert calculus to the more general setting of Hamiltonian torus actions on compact symplectic manifolds with isolated fixed points. Given a generic component of the…

Symplectic Geometry · Mathematics 2009-09-10 R. F. Goldin , S. Tolman

Consider a Hamiltonian torus action on a connected symplectic manifold M for which the associated moment map Phi is proper in some sense. Let Q be a closed submanifold of M. We show that under certain local conditions on Q one has…

Symplectic Geometry · Mathematics 2007-05-23 Michael Otto

Any finite simplicial complex K and a partition of the vertex set of K determines a canonical quotient space of the moment-angle complex of K. We prove that the cohomology groups of such a space can be computed via some Hochster's type…

Algebraic Topology · Mathematics 2019-02-01 Li Yu

In this paper we determine the homotopy types of the reduced suspension space of certain connected orientable closed smooth $5$-manifolds. As applications, we compute the reduced $K$-groups of $M$ and show that the suspension map between…

Algebraic Topology · Mathematics 2024-03-21 Pengcheng Li , Zhongjian Zhu

We define inductively a sequence of purely algebraic invariants - namely, classes in the Quillen cohomology of the Pi-algebra \pi_* X - for distinguishing between different homotopy types of spaces. Another sequence of such cohomology…

Algebraic Topology · Mathematics 2009-10-31 David Blanc

We show that the problem of deciding membership in the moment polytope associated with a finite-dimensional unitary representation of a compact, connected Lie group is in NP and coNP. This is the first non-trivial result on the…

Computational Complexity · Computer Science 2017-06-27 Peter Bürgisser , Matthias Christandl , Ketan D. Mulmuley , Michael Walter

The discriminant method is a tool for describing the cohomology, or the homotopy type, of certain spaces of smooth maps with uncomplicated singularities from a smooth compact manifold L to R^k. We recast some of it in the language of…

Algebraic Topology · Mathematics 2013-08-20 Rui M. G. Reis , Michael S. Weiss

Given a multisymplectic manifold $(M,\omega)$ and a Lie algebra $\frak{g}$ acting on it by infinitesimal symmetries, Fregier-Rogers-Zambon define a homotopy (co-)moment as an $L_{\infty}$-algebra-homomorphism from $\frak{g}$ to the…

Differential Geometry · Mathematics 2016-10-28 Leonid Ryvkin , Tilmann Wurzbacher

In [GT], Goldin and the second author extend some ideas from Schubert calculus to the more general setting of Hamiltonian torus actions on compact symplectic manifolds with isolated fixed points. (See also [Kn99] and [Kn08].) The main goal…

Symplectic Geometry · Mathematics 2012-07-30 Silvia Sabatini , Susan Tolman

Consider a closed non-degenerate 3-form $\omega$ with an infinitesimal action of a Lie algebra $\mathfrak{g}$. Motivated by the fact that the observables associated to $\omega$ form a Lie 2-algebra, we introduce homotopy moment maps defined…

Differential Geometry · Mathematics 2020-03-16 Leyli Mammadova , Marco Zambon

We derive moment identities for the stochastic integrals of multiparameter processes in a random-connection model based on a point process admitting a Papangelou intensity. Those identities are written using sums over partitions, and they…

Probability · Mathematics 2019-04-23 Nicolas Privault

Let P be a convex polytope not simple in general. In the focus of this paper lies a simplicial complex K_P which carries complete information about the combinatorial type of P. In the case when P is simple, K_P is the same as dP*, where P*…

Combinatorics · Mathematics 2015-05-08 A. A. Ayzenberg , V. M. Buchstaber

For each prime p, we exhibit pairs of p-groups all of whose integral cohomology groups are isomorphic. The method used involves very little calculation. The groups are exhibited as kernels of homomorphisms from a compact Lie group G to…

Algebraic Topology · Mathematics 2007-12-03 Ian J. Leary

We show that the linear map defined by multiplication with a general bi-homogeneous form between two bi-graduated pieces of the first cohomology of a nonsingular quadric in the projective space is of maximal rank. This is the first non…

Algebraic Geometry · Mathematics 2010-06-29 Salvatore Giuffrida , Renato Maggioni , Riccardo Re
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