EuDML | Browse

Page 1

Displaying 1 – 7 of 7

The degenerate C. Neumann system I: symmetry reduction and convexity

Holger Dullin, Heinz Hanßmann (2012)

Open Mathematics

The C. Neumann system describes a particle on the sphere S n under the influence of a potential that is a quadratic form. We study the case that the quadratic form has ℓ +1 distinct eigenvalues with multiplicity. Each group of m σ equal eigenvalues gives rise to an O(m σ)-symmetry in configuration space. The combined symmetry group G is a direct product of ℓ + 1 such factors, and its cotangent lift has an Ad*-equivariant momentum mapping. Regular reduction leads to the Rosochatius system on S ℓ,...

The Gromov width of complex Grassmannians.

Karshon, Yael, Tolman, Susan (2005)

Algebraic & Geometric Topology

The magnetic geodesic flow on a homogeneous symplectic manifold.

Efimov, D.I. (2005)

Sibirskij Matematicheskij Zhurnal

The Quantum Birkhoff Normal Form and Spectral Asymptotics

San Vũ Ngọc (2006)

Journées Équations aux dérivées partielles

In this talk we explain a simple treatment of the quantum Birkhoff normal form for semiclassical pseudo-differential operators with smooth coefficients. The normal form is applied to describe the discrete spectrum in a generalised non-degenerate potential well, yielding uniform estimates in the energy $E$ . This permits a detailed study of the spectrum in various asymptotic regions of the parameters $(E, ℏ)$ , and gives improvements and new proofs for many of the results in the field. In the completely resonant...

The reduction of the standard k-cosymplectic manifold associated to a regular lagrangian

Adara M. Blaga (2007)

Banach Center Publications

The aim of the paper is to define a k-cosymplectic structure on the standard k-cosymplectic manifold associated to a regular Lagrangian and to reduce it via Marsden-Weinstein reduction.

The space of clouds in Euclidean space.

Hausmann, Jean-Claude, Rodriguez, Eugenio (2004)

Experimental Mathematics

Toric structures on near-symplectic 4-manifolds

David T. Gay, Margaret Symington (2009)

Journal of the European Mathematical Society

A near-symplectic structure on a 4-manifold is a closed 2-form that is symplectic away from the 1-dimensional submanifold along which it vanishes and that satisfies a certain transversality condition along this vanishing locus. We investigate near-symplectic 4-manifolds equipped with singular Lagrangian torus fibrations which are locally induced by effective Hamiltonian torus actions. We show how such a structure is completely characterized by a singular integral affine structure on the base of...