Zobrazeno 1 - 10
of 1 124
pro vyhledávání: '"Tudor S"'
Publikováno v:
Geometric Methods in Physics XXXX, Workshop, Bia{\l}owie\.za, Poland, Springer, 2023
The restricted Siegel disc is a homogeneous space related to the connected component $T_0(1)$ of the Universal Teichm\"uller space via the period mapping. In this paper we show that it is a coadjoint orbit of the universal central extension of the re
Externí odkaz:
http://arxiv.org/abs/2405.13533
Autor:
Diez, Tobias, Ratiu, Tudor S.
We initiate the study of the norm-squared of the momentum map as a rigorous tool in infinite dimensions. In particular, we calculate the Hessian at a critical point, show that it is positive semi-definite along the complexified orbit, and determine a
Externí odkaz:
http://arxiv.org/abs/2405.13308
We analyze discrete optimal control problems and their connection with back propagation and deep learning. We consider in particular the symmetric representation of the discrete rigid body equations developed via optimal control analysis and optimal
Externí odkaz:
http://arxiv.org/abs/2404.06556
Publikováno v:
Forum of Mathematics, Sigma, Vol 4 (2016)
This paper develops the theory of multisymplectic variational integrators for nonsmooth continuum mechanics with constraints. Typical problems are the impact of an elastic body on a rigid plate or the collision of two elastic bodies. The integrators
Externí odkaz:
https://doaj.org/article/d158b8404a94470b8be0e994f8fb57b9
Autor:
Ratiu, Tudor S., Ziegler, Francois
Publikováno v:
Commun. Contemp. Math. Vol. 24, No. 4 (2022) 2150057 (13 pages)
Frobenius reciprocity asserts that induction from a subgroup and restriction to it are adjoint functors in categories of unitary G-modules. In the 1980s, Guillemin and Sternberg established a parallel property of Hamiltonian G-spaces, which (as we sh
Externí odkaz:
http://arxiv.org/abs/2007.09434
Autor:
Diez, Tobias, Ratiu, Tudor S.
The space of smooth sections of a symplectic fiber bundle carries a natural symplectic structure. We provide a general framework to determine the momentum map for the action of the group of bundle automorphism on this space. Since, in general, this a
Externí odkaz:
http://arxiv.org/abs/2002.01273
Autor:
Diez, Tobias, Ratiu, Tudor S.
Given a closed surface endowed with a volume form, we equip the space of compatible Riemannian structures with the structure of an infinite-dimensional symplectic manifold. We show that the natural action of the group of volume-preserving diffeomorph
Externí odkaz:
http://arxiv.org/abs/1909.11551
Autor:
Ratiu, Tudor S., Zung, Nguyen Tien
The main purpose of this paper is to investigate commuting flows and integrable systems on the configuration spaces of planar linkages. Our study leads to the definition of a natural volume form on each configuration space of planar linkages, the not
Externí odkaz:
http://arxiv.org/abs/1909.09707
In this paper we prove the existence of a simultaneous local normalization for couples $(X,\mathcal{G})$, where $X$ is a vector field which vanishes at a point and $\mathcal{G}$ is a singular underlying geometric structure which is invariant with res
Externí odkaz:
http://arxiv.org/abs/1904.09784