arXiv research

Researchers describe Casimir functions for 3- and 4-step nilpotent Lie groups.

We study the geometrical structure of the coadjoint orbits of an arbitrary complex or real Lie algebra ${\mathfrak g}$ containing some ideal ${\mathfrak n}$. It is shown that any coadjoint orbit in ${\mathfrak g}^*$ is a bundle with the affine subspace of ${\mathfrak g}^*$ as its fibre. This fibre is an isotropic subma…

Constructs infinite-dimensional Siegel disc as symplectic and Kaehler quotient.

We prove that there exists a geometric bijection between the sets of adjoint and coadjoint orbits of a semidirect product, provided a similar bijection holds for particular subgroups. We also show that under certain conditions the homotopy types of any two orbits in bijection with each other are the same. We apply our …

For a Lie groupoid $\mathcal{G}$ with Lie algebroid $A$, we realize the symplectic leaves of the Lie-Poisson structure on $A^*$ as orbits of the affine coadjoint action of the Lie groupoid $\mathcal{J}\mathcal{G}\ltimes T^*M$ on $A^*$, which coincide with the groupoid orbits of the symplectic groupoid $T^*\mathcal{G}$ …

The paper studies a special Grassmannian space and shows it's an orbit of a unitary group.

The paper finds symplectic compactifications of coadjoint orbits.

This thesis studies the symplectic structure of holomorphic coadjoint orbits, and their projections. A holomorphic coadjoint orbit O is an elliptic coadjoint orbit which is endowed with a natural invariant Kählerian structure. These coadjoint orbits are defined for a real semi-simple connected non-compact Lie group G w…

Study vortex loops as coadjoint orbits of diffeomorphisms.

Unified framework for smooth structures on coadjoint orbits.

Study pseudo-Riemannian metrics on Jordan superalgebras.

Study nonlinear flags as coadjoint orbits of Hamiltonian diffeomorphisms.

The paper classifies foliations formed by generic coadjoint orbits of specific Lie groups.

For a complex Lie group $G$ with a real form $G_0\subset G$, we prove that any Hamiltionian automorphism $φ$ of a coadjoint orbit $\mathcal O_0$ of $G_0$ whose connected components are simply connected, may be approximated by holomorphic $\mathcal O_0$-invariant symplectic automorphism of the corresponding coadjoint or…

Study isotropic embeddings of Lie group orbits and their application to magnetic geodesic flows.

Let $G$ be a linear connected complex reductive Lie group. The purpose of this paper is to give explicit symplectic isomorphisms from twisted cotangent bundles of the complex generalized flag varieties, whose transition functions are given by affine transformations instead of linear transformations, onto the complex co…

Geometric quantization shows compatibility of symmetries on coadjoint orbits and Kähler-Einstein manifolds.

Study of weighted nonlinear flags in symplectic geometry.

Contact Lie algebras have specific properties related to stabilizers and invariant polynomials.

The abstract describes a foliation of orbits for a specific class of Lie groups.

This thesis explores Hamiltonian systems and Kähler structures on complex coadjoint orbits.

Geometric integrator preserves coadjoint orbits in dissipative systems.

We study the general geometrical structure of the coadjoint orbits of a semidirect product formed by a Lie group and a representation of this group on a vector space. The use of symplectic induction methods gives new insight into the structure of these orbits. In fact, each coadjoint orbit of such a group is obtained b…

We investigate, in some details, symplectic equivalence between several conformal classes of Lorentz metrics on the hyperboloid of one sheet $H^{1,1} \cong T \times T - Δ$ and affine coadjoint orbits of the group $Diff_+(Δ)$ of orientation preserving diffeomorphisms of $Δ\cong T$ with its natural projective structure. …

The main goal of this paper is to compute the characteristic class of the Alekseev-Lachowska *-product on coadjoint orbits. We deduce an analogue of the Weyl dimension formula in the context of deformation quantization.

We apply the Guillemin-Lerman-Sternberg theorem to reprove a formula of Heckman for the Duistermaat-Heckman measure associated to the coadjoint action of $T$, a maximal torus of a compact semisimple Lie group $G$, on a regular coadjoint $G$-orbit in the dual space of the Lie algebra of $G$. This formula is, in an appro…

We study the adjoint and coadjoint representations of a class of Lie group including the Euclidean group. Despite the fact that these representations are not in general isomorphic, we show that there is a geometrically defined bijection between the sets of adjoint and coadjoint orbits of such groups. In addition, we sh…

Coadjoint orbits for the group SO(6) parametrize Riemannian G-reductions in six dimensions, and we use this correspondence to interpret symplectic fibrations between these orbits, and to analyse moment polytopes associated to the standard Hamiltonian torus action on the coadjoint orbits. The theory is then applied to d…

A Poisson-Lie group acting by the coadjoint action on the dual of its Lie algebra induces on it a non-trivial class of quadratic Poisson structures extending the linear Poisson bracket on the coadjoint orbits.

We give an identification of the triple reduced product of three coadjoint orbits in SU(3) with a space of Hitchin pairs over a genus 0 curve with three punctures, where the residues of the Higgs field at the punctures are constrained to lie in fixed coadjoint orbits. Using spectral curves for the corresponding Hitchin…

This paper develops a geometric framework for Wilson surfaces in higher gauge theory.

Study convex hulls of orbits for compact groups, defining new invariants related to polynomial degrees.

Quantum systems on coadjoint orbits yield spectra matching Dolbeault and de Rham indices.

The study examines Kähler structures on coadjoint orbits of Lie groups using coherent and squeezed states.

Study on deformation of affine structures on Lie groups using cohomology.

Let G_R be a Lie group acting on an oriented manifold M, and let $ω$ be an equivariantly closed form on M. If both G_R and M are compact, then the integral $\int_M ω$ is given by the fixed point integral localization formula (Theorem 7.11 in [BGV]). Unfortunately, this formula fails when the acting Lie group G_R is not…

The cohomology of affine structures on Lie groups is compared with that of Koszul-Vinberg algebras.

For a given manifold $M$ we consider the non-linear Grassmann manifold $Gr_n(M)$ of $n$-dimensional submanifolds in $M$. A closed $(n+2)$-form on $M$ gives rise to a closed 2-form on $Gr_n(M)$. If the original form was integral, the 2-form will be the curvature of a principal $S^1$-bundle over $Gr_n(M)$. Using this $S^…

Abstract: Bijection strengthened to Morita equivalence integrating Poisson and Cartan-Dirac structures.

Gauge theory connects hyperbolic metrics to Virasoro orbits, revealing their geometric and topological properties.

The paper calculates quantum cohomology for coadjoint orbits and Hamiltonian groups.

Researchers create a new metric on complex projective space bundles.

Jordan algebras in information geometry linked to metrics on probability distributions.

Dual pairs constructed for volume preserving diffeomorphisms using symplectic geometry.

We investigate some basic questions concerning the relationship between the restricted Grassmannian and the theory of Banach Lie-Poisson spaces. By using universal central extensions of Lie algebras, we find that the restricted Grassmannian is symplectomorphic to symplectic leaves in certain Banach Lie-Poisson spaces, …

We show that the leaves of an LA-groupoid which pass through the unit manifold are, modulo a connectedness issue, Lie groupoids. We illustrate this phenomenon by considering the cotangent Lie algebroids of Poisson groupoids thus obtaining an interesting class of symplectic groupoids coming from their symplectic foliati…

The coadjoint orbits of compact Lie groups carry many Kähler structures, which include a Riemannian metric and a complex structure. We provide a fairly explicit formula for the Levi-Civita connection of the Riemannian metric, and we use the complex structure to give a fairly explicit construction of a canonical Dirac o…

New model calculates Wilson surfaces in higher gauge theory.