{"id":26,"date":"2025-07-20T22:53:03","date_gmt":"2025-07-20T20:53:03","guid":{"rendered":"https:\/\/wp.ull.es\/8ibmgmft\/?page_id=26"},"modified":"2026-02-02T22:53:25","modified_gmt":"2026-02-02T21:53:25","slug":"programme","status":"publish","type":"page","link":"https:\/\/wp.ull.es\/8ibmgmft\/programme\/","title":{"rendered":"PROGRAMME"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"26\" class=\"elementor elementor-26\">\n\t\t\t\t<div class=\"elementor-element elementor-element-647de3d6 e-flex e-con-boxed rael-particle-no e-con e-parent\" data-id=\"647de3d6\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;rae_animations_entrance&quot;:&quot;none&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-262f001 elementor-widget elementor-widget-image\" data-id=\"262f001\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"526\" src=\"https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4.jpg\" class=\"attachment-full size-full wp-image-586\" alt=\"\" srcset=\"https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4.jpg 1024w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-300x154.jpg 300w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-768x395.jpg 768w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-100x51.jpg 100w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-150x77.jpg 150w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-200x103.jpg 200w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-450x231.jpg 450w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-600x308.jpg 600w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/4-900x462.jpg 900w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-58754f5 elementor-widget elementor-widget-image\" data-id=\"58754f5\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"1024\" height=\"546\" src=\"https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario.jpg\" class=\"attachment-full size-full wp-image-570\" alt=\"\" srcset=\"https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario.jpg 1024w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-300x160.jpg 300w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-768x410.jpg 768w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-100x53.jpg 100w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-150x80.jpg 150w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-200x107.jpg 200w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-450x240.jpg 450w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-600x320.jpg 600w, https:\/\/wp.ull.es\/8ibmgmft\/wp-content\/uploads\/sites\/231\/2026\/01\/horario-900x480.jpg 900w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d615588 elementor-widget elementor-widget-heading\" data-id=\"d615588\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Plenary Speaker<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6253b73b elementor-widget elementor-widget-text-editor\" data-id=\"6253b73b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<h3><strong>Paula Balseiro (UFF, Brazil)<\/strong><\/h3>\n<p style=\"font-weight: 400\"><strong>Title:<\/strong> <em>\u00a0On conserved measures for nonholonomic systems with symmetries [<a href=\"https:\/\/drive.google.com\/file\/d\/1PfyA2bO84B2jXOUYuokajwHSDhtHI0TT\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><br \/><strong>Abstract:<\/strong> One of the principal differences between Hamiltonian systems\u2014described on symplectic manifolds\u2014and nonholonomic systems is the existence of an invariant volume for the dynamics. However, certain nonholonomic systems also admit an invariant measure. In this talk, we consider nonholonomic systems reduced by the action of a Lie group of symmetries. Under suitable assumptions, we explore the existence of an invariant volume for the underlying geometric structure. This viewpoint provides a geometric insight into the problem; moreover, as a direct consequence, this volume is preserved by the reduced nonholonomic dynamics.<br \/>This is joint work with J.C. Marrero and N. Sansonetto.<\/p>\n<h3><strong>Angel Ballesteros (University of Burgos, Spain)<\/strong><\/h3>\n<p><strong>Title:<\/strong> <em>From quantum reference frames to Poisson-Lie groups\u00a0<\/em><\/p>\n<p><strong>Abstract:<\/strong> The necessity of considering \u201cquantum reference frames\u201d, namely reference frames associated to dynamical material systems obeying the laws of<br \/>quantum theory, has been recently stressed both from quantum information and quantum gravity perspectives. In this talk recent results providing a novel group-<br \/>theoretical framework for such quantum reference frames will be presented. In particular, we demonstrate a correspondence between certain quantum<br \/>reference frame transformations and transformations generated by a quantum group deformation of the centrally extended Galilei group. In this approach,<br \/>since Poisson-Lie groups are just the semiclassical counterpart of quantum groups, the classification of Poisson-Lie structures on the Galilei group<br \/>becomes essential in order to identify and construct the appropriate quantum Galilei group. Moreover, the relativistic generalization of this result can be envisaged by considering a suitable Poisson-Lie structure on the Poincar\u00e9 group and by constructing its associated quantum group deformation.<\/p>\n<h3><strong>Mar\u00eda Barbero (Technical University of Madrid, Spain)\u00a0<\/strong><\/h3>\n<p style=\"font-weight: 400\"><strong>Title:\u00a0<\/strong><em>Discretization maps in optimal control theory {<a href=\"https:\/\/drive.google.com\/file\/d\/1YCJ-qLTSkLBrCRL1V6U_XUPfC5ZVfyPM\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p style=\"font-weight: 400\"><strong>Abstract:\u00a0<\/strong>We have recently introduced in the literature a generalization of retraction maps called discretization maps. They are useful to obtain symplectic numerical integrators by adapting the continuous problem to the discretization rule rather than viceversa, as typically done in numerical integration. Consequently, the manifold where the equations of motion live are discretized, in stead of discretizing the equations.<\/p>\n<p>We will describe how discretization maps can be used to define numerical integrators for optimal control problems so that some structure is preserved.<\/p>\n<h3><strong>Alessandro Bravetti (University of Camerino, Italy)<\/strong><\/h3>\n<p><strong>Title:<\/strong>\u00a0<em>A Geometric Perspective on Asymmetric Relaxation Dynamics [<a href=\"https:\/\/drive.google.com\/file\/d\/1et8wImu4W566gfrMu7GfRxes1ikmtW82\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> Asymmetric relaxation toward equilibrium is a recently-identified phenomenon that has attracted increasing attention in the study of thermodynamic systems. In this talk, we introduce a geometric approach based on gradient flows on appropriate manifolds to describe relaxation dynamics. This framework allows us to formulate a general criterion for determining the emergence of asymmetry in the approach to equilibrium. We conclude by outlining future perspectives and potential extensions.<\/p>\n<h3><strong>Alejandro Cabrera (UFRJ, Brazil)<\/strong><\/h3>\n<p><strong>Title:<\/strong> <em>Local symplectic groupoids, multiplication, and Poisson integrators [<a href=\"https:\/\/drive.google.com\/file\/d\/1WE6s_b0hlnrE1n3OqcEQtIhUmjhssOJl\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> This talk is based on joint work in progress with D. Iglesias and J.C. Marrero. First, we shall overview the role of local symplectic groupoids in the<br \/>construction of Poisson integrators, following O. Cosserat, as well as recent joint work with D. Martin de Diego and M. Vaquero about using approximate<br \/>geometric data. We observe that only the &amp;quot;strict bi-realization&amp;quot; data is used in these approaches, but not groupoid multiplication. We then explain how multiplication &amp;quot;m&amp;quot; can be incorporated into this construction and, also, how generating functions for m can be incorporated yielding a practical numerical algorithm. Finally, we show some illustrative examples and discuss future directions.<\/p>\n<h3><strong>Alberto Ibort (University Carlos III\u00a0 of Madrid, Spain)<\/strong>\u00a0 \u00a0<\/h3>\n<p><b><span lang=\"EN-US\">Title:<\/span><\/b><span lang=\"EN-US\">\u00a0<\/span><em><span lang=\"EN-US\">The multisymplectic formalism for field theories revisited<\/span><\/em><span lang=\"EN-US\"><br \/><\/span><b><span lang=\"EN-US\">Abstract:<\/span><\/b><span lang=\"EN-US\">\u00a0<\/span><span lang=\"EN-US\">The multisymplectic formalism for field theories, so relevant in the description of first order Hamiltonian field theories, will be revisited focusing the attention on its extension to higher order field theories.\u00a0 A novel construction that would provide the dual version of the infinite jet bundle will be presented and discussed.<\/span><\/p>\n<h3><strong>Eduardo Garc\u00eda R\u00edo (University of Santiago de Compostela)<\/strong><\/h3>\n<p><strong>Title:<\/strong> <em>Ricci solitons on Lie groups <span lang=\"EN-US\"> [<a href=\"https:\/\/drive.google.com\/file\/d\/1Lpn3n1vEbBHoNe27XoOFU7cGcOYaS2m4\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/span><\/em><\/p>\n<p><strong>Abstract:<\/strong> Ricci solitons, being self-similar solutions of the Ricci flow have received special attention during the last years. Although a complete description<br \/>of such metris is far from being complete, they are quite well-understood in the homogeneous setting. For instance, Riemannian Ricci solitons on Lie groups<br \/>are homothetic to algebraic ones.<br \/>The Lorentzian situation is much richer, allowing the existence of many Ricci solitons without Riemannian counterpart. Hence our main purpose is to present some classification results for Ricci solitons on low-dimensional Lorentzian Lie groups. We show that any four-dimensional Lie group admits a Ricci soliton left-<br \/>invariant Lorentzian metric. As a consequence some non-Einstein compact Lorentzian Ricci solitons are constructed in dimensions three and four.<br \/>(This is joint work with Rosal\u00eda Rodr\u00edguez-Gigirey and Ram\u00f3n V\u00e1zquez- Lorenzo)<\/p>\n<h3><strong>Francoise Gay-Balmaz (Nanyang Technological University, Singapur)<\/strong><\/h3>\n<p><strong>Title:<\/strong> <em>General Relativistic Fluids: Reduction by Symmetries and Junction <\/em><em>Conditions [<a href=\"https:\/\/drive.google.com\/file\/d\/1PZfC2Y4EIVU9zvlwqARSzBAMBI2cxv9z\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> We introduce a new Lagrangian variational framework for general relativistic fluids, allowing symmetry reduction in the relativistic context. By<br \/>including Gibbons-Hawking-York (GHY) boundary terms, this approach naturally produces the Israel-Darmois junction conditions, connecting the fluid\u2019s<br \/>internal dynamics to the gravitational field in the exterior spacetime.<\/p>\n<h3>Katarzyna\u00a0Grabowska (University of Warsaw, Poland)<\/h3>\n<p><strong>Title:<\/strong> <em>Affine Dirac aglebroids in nonholonomic mechanics [<a href=\"https:\/\/drive.google.com\/file\/d\/1iVBJf1e2Ioyc8YZPVEcA5ghyuQcDgPjz\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><br \/><strong>Abstract:<\/strong> The concept of a Dirac algebroid, a linear almost Dirac structure on a vector bundle, was introduced to generate phase equations for mechanical<br \/>systems with linear nonholonomic constraints. It was successfully applied to systems described by the so-called mechanical Lagrangian or Hamiltonian, as well as systems with magnetic-like or gyroscopic potentials. In contrast to other structures reported in the literature in this context, the Dirac algebroid we use is built only from constraints and canonical geometric structures of the underlying bundles and is universal, in the sense that it is independent of the particular Hamiltonian or Lagrangian. This approach can be readily generalized to affine nonholonomic constraints via the concept of an affine Dirac algebroid. During the talk, we will recall the main ideas and provide examples.<\/p>\n<p>References<br \/>[1] Grabowska, K., and Grabowski, J. Dirac algebroids in Lagrangian and Hamiltonian mechanics, Journal of Geometry and Physics, 61 (2011),\u00a02233\u20132253.<br \/>[2] Garc\u00eda-Naranjo, L. C., Marrero, J. C., de Diego, D. M., and Vald\u00e9s, E. P. P. Almost-Poisson brackets for nonholonomic systems with gyroscopic terms and Hamiltonisation, J Nonlinear Sci 32 (2024)<br \/>[3] Grabowska K, Borczy\u0144ska M., Majsak J., and Sobczak, T. Dirac structures in. nonholonomic mechanics, arXiv:2504.18853<\/p>\n<h3>Janusz Grabowski (IMPAN, Poland)<\/h3>\n<div>\n<div><strong>Title:<\/strong> <em>Lifting contact and Jacobi structures [<a href=\"https:\/\/drive.google.com\/file\/d\/1wY3lnBeeLkfLC-tPYknrYY4tyP4ESofC\/view?usp=drive_link\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/div>\n<div><strong>Abstract:<\/strong> Contact structures, understood as maximally non-integrable hyperplane distributions, admit canonical symplectizations in the form of<\/div>\n<div>homogeneous symplectic principal bundles with structure group \u211d \u00d7 , the multiplicative group of nonzero real numbers.<\/div>\n<div>A natural generalization of this picture is given by principal \u211d \u00d7 -bundles endowed with homogeneous Poisson structures \u2014 Poissonizations of Jacobi structures understood as Jacobi bundles, as introduced by Marle [3]. This correspondence was further generalized in our joint work [1] with D. Iglesias, J. C. Marrero, E. Padr\u00f3n, and P. Urb\u00e1nski.We will present an\u00a0 introduction to Jacobi structures defined by Lie brackets on sections of line bundles, together with the construction of their canonical Poissonizations. We will also discuss tangent and phase lifts of principal \u211d- actions, which can be used to lift Jacobi structures and to associate Lie algebroids with Jacobi bundles. This approach goes back to an earlier joint paper [2] with G. Marmo. As a particular example, we will describe a canonical lift of contact structures \u2014 an analogue of the tangent lift of symplectic forms.<\/div>\n<div>\u00a0<\/div>\n<div><strong>References<\/strong><\/div>\n<div>[1] J. Grabowski, D. Iglesias, J. C. Marrero, E. Padr\u00f3n, P. Urb\u00e1nski, Poisson-\u00a0<span style=\"font-size: 16px;text-transform: inherit\">Jacobi reduction of homogeneous tensors, J. Phys. A, 37 (2004), 5383\u20135399.<\/span><\/div>\n<div>[2] J. Grabowski, G. Marmo, Jacobi structures revisited, J. Phys. A 34 (2001),\u00a0<span style=\"font-size: 16px;text-transform: inherit\">10975\u201310990.<\/span><\/div>\n<div>[3] C. M. Marle, On Jacobi manifolds and Jacobi bundles, in \u201dSymplectic\u00a0<span style=\"font-size: 16px;text-transform: inherit\">geometry, groupoids, and integrable systems\u201d (Berkeley, CA, 1989), 227\u2013246,<\/span><\/div>\n<div>Math. Sci. Res. Inst. Publ. 20, Springer,New York, 1991.<\/div>\n<\/div>\n<h3>Sergio Grillo (Instituto Balseiro, Bariloche, Argentina)<\/h3>\n<p><strong>Title:<\/strong> <em>Variational reduction of homogeneous presymplectic Hamiltonian systems [<a href=\"https:\/\/drive.google.com\/file\/d\/1mGp6QpIc7IB8YjLOhMjaW3wFVGkmJ0RI\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> Given a homogeneous (symplectic) Hamiltonian system on a manifold $M$, with respect to a principal action $\\mathbb{R}^{+}\\times M\\rightarrow M$, we have shown in a previous paper that an associated reduced system can be defined (unless locally), and it is given by a contact Hamiltonian system on $M\/\\mathbb{R}^{+}$. Moreover, we have written a related reconstruction equation and solved it up to quadratures. In this talk we extend our study to the case of homogeneous pre-symplectic Hamiltonian systems, but focusing on the variational formulation of them. We show that (unless locally) a reduced variational principle can be associated to such systems, in such a way that the trajectories of the original system can be reconstructed from the critical points of the mentioned reduced principle. As a by-product, we obtain a variational formulation for all the contact Hamiltonian systems, which offers an alternative to the so-called Herglotz variational principle.<\/p>\n<h3>Manuel de Le\u00f3n (ICMAT-CSIC and Real academia de Ciencias de Espa\u00f1a, Spain)<\/h3>\n<div>\n<p style=\"margin: 0cm;font-size: medium;font-family: Calibri, sans-serif;color: #000000\"><span style=\"color: #808080\"><b><span lang=\"EN-US\">Title: <\/span><\/b><em><span lang=\"EN-US\">New geometric structures in thermodynamics [<a href=\"https:\/\/drive.google.com\/file\/d\/19dy8DGxXs3zz-D71jVsbyMvccfV4d6tI\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/span><\/em><\/span><\/p>\n<p style=\"margin: 0cm;font-size: medium;font-family: Calibri, sans-serif;color: #000000\"><span style=\"color: #808080\"><strong style=\"font-family: Georgia, 'Times New Roman', 'Bitstream Charter', Times, serif;font-size: 16px\">Abstract:<\/strong><\/span><span style=\"color: #333333;font-family: Georgia, 'Times New Roman', 'Bitstream Charter', Times, serif;font-size: 16px\">\u00a0<\/span><span lang=\"EN-US\" style=\"color: #333333;font-family: Georgia, 'Times New Roman', 'Bitstream Charter', Times, serif;font-size: 16px\">Traditionally, the geometry of equilibrium thermodynamics has been mainly studied via contact geometry; in this geometric setting, thermodynamic properties are encoded by Legendre submanifolds of the thermodynamic phase space. In this lecture, we will show how different thermodynamic systems can be described using new geometric structures called partially cosymplectic and partially cosymplectic structures of higher order. Indeed, partially cosymplectic structures could be considered as natural extensions of contact geometry, even if they exhibit very different features. This geometric approach allows us to obtain discretisations of the thermodynamic systems and construct very convenient numerical integrators.<\/span><\/p>\n<\/div>\n<h3>Giuseppe Marmo (University of Napoli)<\/h3>\n<p><strong>Title:<\/strong>\u00a0<em>Differential Geometry of Quantum Evolution [<a href=\"https:\/\/drive.google.com\/file\/d\/1kF-lxNatwvp9ff5cg-0Z1Yi5Rtw3kZzb\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:\u00a0<\/strong>The description of any physical system requires the identification of:\u00a0Observables, say O; States, say S; A probability map pairing observables and states with values in\u00a0probability measures on the real line; Evolution equations of motion; A composition\/decomposition\u00a0rule for composing\/decomposing systems.\u00a0<\/p>\n<p>In this talk we shall consider as primary choice the evolution on the manifold of\u00a0observables, i.e., we take a dynamical point of view rather than a kinematical one. The additional structures which are required on observables or states because of the physical\u00a0interpretation shall be compatible with a given dynamics. This statement is usually implemented\u00a0 by requiring that the Lie derivative, with respect to the vector field describing the evolution ,of the\u00a0 tensor fields describing the additional geometrical structures identically vanishes. This ideology is fully developed in the book Geometry from Dynamics, Classical and\u00a0 Quantum, there Quantum Mechanics is considered in the Hilbert Space picture and the evolution\u00a0 is given by a vector field on the manifold of states.\u00a0<\/p>\n<p>Here we consider Quantum Mechanics in the C*-algebraic setting, evolution being described by a\u00a0vector field on the manifold of observables. We will show that alternative structures of Lie-Jordan\u00a0 algebras on the manifold of observables are possible. This would be the analog (Dirac\u2019s Analogy\u00a0 Principle)of alternative compatible Poisson structures invariant under Classical Evolution.\u00a0<\/p>\n<p><strong>Reference: <\/strong>J.F.Carinena, A.Ibort, G.Marmo, G.Morandi. Geometry from Dynamics,Classical and Quantum.\u00a0Springer, 2015<\/p>\n<h3>David Mart\u00edn de Diego\u00a0 (ICMAT, Spain)<\/h3>\n<div><span style=\"font-size: medium\"><b>Title:<\/b>\u00a0<em>Discrete mechanics and variational integrators [<a href=\"https:\/\/drive.google.com\/file\/d\/186p0uOZh7WbNvd0IFOCacNK2Ex5ewqKH\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/span><\/div>\n<div><b><span style=\"font-size: medium\">Abstract:\u00a0 <\/span><\/b><span style=\"font-size: medium\">Among the many mathematical results obtained by Juan Carlos Marrero and his collaborators, this talk will focus on some important contributions related to discrete mechanics. In [1,2,3,4] we describe discrete Lagrangian mechanical systems on Lie groupoids, their Hamiltonian counterparts, and their extension to nonholonomic systems [5]. These constructions are relevant for the development of new geometric integrators, in particular for the numerical integration of dynamical systems with symmetry. In this talk, we review these results and discuss further developments.<\/span><\/div>\n<div>\u00a0<\/div>\n<div><b><span style=\"font-size: medium\">References:<\/span><\/b><\/div>\n<div><span style=\"font-size: medium\">[1] Marrero, Juan C; \u00a0Mart\u00edn de Diego, David, \u00a0Mart\u00ednez, Eduardo: \u00a0Discrete Lagrangian and Hamiltonian mechanics on Lie groupoids. Nonlinearity 19 (2006), no. 6, 1313\u20131348.<\/span><\/div>\n<div><span style=\"font-size: medium\">[2] Cort\u00e9s, Jorge; de Le\u00f3n, Manuel; Marrero, Juan C.; Mart\u00edn de Diego, D.; Mart\u00ednez, Eduardo: A survey of Lagrangian mechanics and control on Lie algebroids and groupoids. Int. J. Geom. Methods Mod. Phys. 3 (2006), no. 3, 509\u2013558.<\/span><br \/><span style=\"font-size: medium;color: #333333;text-transform: inherit\">[3] \u00a0Marrero, Juan C; \u00a0Mart\u00edn de Diego, David, \u00a0Mart\u00ednez, Eduardo: The local description of discrete mechanics. \u00a0Fields Inst. Commun., 73 Springer, New York, 2015, 285\u2013317.<\/span><\/div>\n<div><span style=\"font-size: medium\">[4] \u00a0Marrero, Juan Carlos; de Diego, David Mart\u00edn; Mart\u00ednez, Eduardo: \u00a0Local convexity for second order differential equations on a Lie algebroid. J. Geom. Mech. 13 (2021), no. 3, 477\u2013499.<\/span><\/div>\n<div><span style=\"font-size: medium;text-transform: inherit;color: #000000;font-family: Helvetica\">[5]\u00a0<\/span><span style=\"font-size: medium;text-transform: inherit\">Iglesias, David; Marrero, Juan C.; de Diego, David Mart\u00edn; Mart\u00ednez, Eduardo. Discrete nonholonomic Lagrangian systems on Lie groupoids. J. Nonlinear Sci. 18 (2008), no. 3, 221\u2013276.<\/span><\/div>\n<div>\n<div>\u00a0<\/div>\n<div><span style=\"color: #333333;font-size: 20px;font-weight: bold;text-transform: inherit\">Tom Mestdag (University Antwerp, Belgium)\u00a0<\/span><\/div>\n<\/div>\n<p><strong style=\"font-size: 16px;color: #7a7a7a;text-transform: inherit\">Title<\/strong><span style=\"font-size: 16px;color: #7a7a7a;text-transform: inherit\">: <\/span><em style=\"font-size: 16px;color: #7a7a7a;text-transform: inherit\">The invariant inverse problem and EDS on Lie algebroids [<a href=\"https:\/\/drive.google.com\/file\/d\/1QNzRxcraftqbQTnwTfSfs2wYdUGujI5D\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong style=\"font-size: 16px;color: #7a7a7a;text-transform: inherit\">Abstract:<\/strong><span style=\"font-size: 16px;color: #7a7a7a;text-transform: inherit\"> Given an invariant system of second-order ODEs on a Lie group, when does an invariant Lagrangian exist? This question is the so-called \u00abinvariant\u00bb; inverse problem. In this talk, we discuss some aspects of the problem, and we explain how it fits within the context <\/span><span style=\"font-size: 16px;color: #7a7a7a;text-transform: inherit\">of exterior differential systems (EDS), once we have extended EDS theory from manifolds (and their tangent bundles) to Lie algebroids.<\/span><\/p>\n<h3><strong>Antonio de Nicola (University of Salerno, Italy)<\/strong><\/h3>\n<p><strong>Title:<\/strong> <em>Darboux-Lie Derivatives: a unified calculus for G-structures [<a href=\"https:\/\/drive.google.com\/file\/d\/1kEVJUooZyS2VvEoey73O6VGiL0tygeUS\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> In the theory of G-structures on manifolds, geometric structures are often described in terms of gauge equivalence classes of soldering forms.<br \/>However, a comprehensive calculus of derivatives for such forms and their gauge transformations has been lacking. In this talk, based on joint work with<br \/>Ivan Yudin, I will introduce the concept of the Darboux-Lie derivative, a new tool designed to fill this gap.\u00a0<\/p>\n<p>We define the Darboux-Lie derivative for fiber bundle maps from natural bundles to associated fiber bundles. This construction generalizes the <em>metamathematical<\/em> notion of a derivative, utilizing the Trautman lift as a very general framework. I will demonstrate how this single operator unifies various<br \/>classical concepts, showing that the standard Lie derivative, the covariant derivative, and the classical Darboux derivative for group valued maps are all<br \/>specific instances of the Darboux-Lie derivative.<br \/>Key properties of this new derivative will be discussed, including:<\/p>\n<ul>\n<li>Its behavior on products, tensor products, and compositions (Leibniz and chain rules).<\/li>\n<li>Its expression in terms of flows.<\/li>\n<li>The derivation of a Cartan-type magic formula for the covariant Darboux-Lie derivative.<\/li>\n<\/ul>\n<p>Finally, I will briefly outline applications to G-structures, specifically how this derivative characterizes infinitesimal automorphisms and torsion-free conditions.<\/p>\n<h3>Narciso Rom\u00e1n Roy (Technical University of Catalonia, Poland)<\/h3>\n<p><strong>Title:<\/strong> <em>Multicontact field theories: Foundations, symmetries and perspectives [<a href=\"https:\/\/drive.google.com\/file\/d\/1JJaRGyTcRY__SpCNaMRADI5640CpO3M6\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:\u00a0<\/strong>A new geometric framework\u2014based on contact and multisymplecticgeometry\u00a0 and known as multicontact structure\u2014 has recently been developed<br \/>to model action-dependent field theories. The purpose of this talk is, first, to review the foundations of multicontact geometry\u00a0and its use in formulating the<br \/>Lagrangian and Hamiltonian descriptions of such theories.\u00a0 Second, we examine their non-conservative features, introducing precise notions ofsymmetries and the\u00a0 corresponding dissipation laws,\u00a0 and establishing an adapted version of Noether\u2019s theorem.\u00a0 Finally, we outline several physical applications and discuss current perspectives and future developments in the field.<\/p>\n<p><strong>References:<\/strong><\/p>\n<p>1. M. de Le\u00f3n, J. Gaset, M. C. Mu\u00f1oz-Lecanda, X. Rivas, and N. Rom\u00e1n- Roy. <em>Multicontact formulation for non-conservative field theories<\/em>, J. Phys. A: Math.<br \/>Theor.\u00a056(2) (2023) 025201. DOI: 10.1088\/1751-8121\/acb575.<br \/>2. M. de Le\u00f3n, J. Gaset, M. C. Mu\u00f1oz-Lecanda, X. Rivas, and N. Rom\u00e1n-Roy. <em>Practical introduction to action-dependent field theories,<\/em> Fortschr. Phys. 7(5)<br \/>(2025) e70000. DOI: 10.1002\/prop.70000.<br \/>3. X. Rivas, N. Rom\u00e1n-Roy, and B.M. Zawora.<em> Symmetries and Noether\u2019s <\/em><em>theorem for multicontact field theories<\/em>,\u00a0Lett. Math. Phys.\u00a0115\u00a0(2025) 108. DOI:<br \/>10.1007\/s11005-025-01995-0.<br \/>4. M. de Le\u00f3n, R. Izquierdo-L\u00f3pez, and X Rivas. <em>Brackets in multicontact geometry and multisymplectization<\/em>, arXiv:2505.13224 (2025).<\/p>\n<h3>Arjan van der Schaft (University of Groningen, Netherlands)<\/h3>\n<p><strong>Title:<\/strong> <em>On the Geometry and Dynamics of Engineering Systems [<a href=\"https:\/\/drive.google.com\/file\/d\/1of2GMHCZEKvf_ap1xt5MIik_lviscTv2\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> Mechanics has always provided an immensely fruitful playing ground for the development of mathematics; from Hamiltonian dynamics, variational<br \/>principles, to geometric mechanics. The aim of this talk is to indicate that, next to the mechanical system case, there is a vast area of other physical systems<br \/>that, perhaps equally well, gives rise to interesting dynamical and geometric developments. In particular, we will consider classes of systems originating from<br \/>engineering. Complex engineering systems are often composed of subsystems stemming from different physical domains (mechanical, electrical, chemical,<br \/>etc.). This necessitates the consideration of a unified framework for the modeling and analysis of multi-physics systems, and has given rise to the<br \/>geometric theory of port-Hamiltonian systems. While the geometry of mechanical systems is, loosely speaking, based on the geometry of the cotangent bundle of the configuration manifold (with extensions to, e.g., symplectic and Poisson manifolds), the basic geometry of port-Hamiltonian systems is provided by the notion of a Dirac structure. Differently from the mechanical case, this Dirac structure is also determined by the interconnection structure of the system, as exemplified by Kirchhoff\u2019s current and voltage laws.<br \/>Furthermore, port-Hamiltonian systems theory admits the inclusion of energy-dissipation (which is essential to most engineering and natural systems), algebraic constraints, and interaction with the environment (through inputs and outputs). Special emphasis in this talk will be given to relaxation systems, which are port-Hamiltonian systems with only one type of energy storage (and hence no oscillatory behavior). It will be shown that such systems admit an alternative geometric description as gradient systems, where the Riemannian metric is given by the inverse of the Hessian matrix of the energy function (Hamiltonian).<br \/>Furthermore the dissipation potential qualifies as a candidate Lyapunov function, different from the Hamiltonian. This extends the Brayton-Moser formulation and analysis of nonlinear electrical networks, and provides interesting links to convex analysis. As an appealing example, we will also discuss continuous Hopfield neural networks from this perspective.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph {\"kioblocks\":[]} --><\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph {\"kioblocks\":[]} --><\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph {\"kioblocks\":[]} --><\/p>\n<p><!-- \/wp:paragraph --><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-2b0bba0 e-flex e-con-boxed rael-particle-no e-con e-parent\" data-id=\"2b0bba0\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;rae_animations_entrance&quot;:&quot;none&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-fe3eaf3 elementor-widget elementor-widget-heading\" data-id=\"fe3eaf3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Short talk <\/h2>\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-b7a7ff1 e-flex e-con-boxed rael-particle-no e-con e-parent\" data-id=\"b7a7ff1\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;rae_animations_entrance&quot;:&quot;none&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-7e98e05 elementor-widget elementor-widget-text-editor\" data-id=\"7e98e05\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<h3>Alexander Anahory (IE University, Spain)<\/h3>\n<p><strong>Title<\/strong>: <em>Mechanical Hamiltonization of unreduced Chaplygin systems [<a href=\"https:\/\/drive.google.com\/file\/d\/1yZyU4JEDKEFFC2c06QFINugFRuhjWHZX\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> In a recent paper, we proved that the trajectories of unreduced $\\phi$-simple Chaplygin kinetic systems are reparametrizations of horizontal geodesics with respect to a modified Riemannian metric. In this talk, we will show how one can construct these Riemannian metrics, which are not unique,<br \/>and see them in specific examples. We also extend these results to mechanical systems with invariant potential (not necessarily kinetic).<\/p>\n<h3>Miguel \u00c1ngel Berbel (Universidad Pontificia Comillas, Spain)<\/h3>\n<p><strong>Title<\/strong>: <em>Reconstruction in Lie-Poisson reduction for field theories.<\/em><\/p>\n<p><strong>Abstract:<\/strong> Any reduction procedure naturally poses a reconstruction problem: given a solution of the reduced system, can one recover a corresponding solution of the original unreduced problem? While reconstruction is always possible in mechanics, in Euler\u2013Poincar\u00e9 and Lagrange\u2013Poincar\u00e9 reduction for field theories, the obstruction to reconstruction is characterised by the curvature of a connection constructed from the reduced solution. Far less is known, however, in the Poisson\u2013covariant formulation of Hamiltonian field theories. In this talk, we present explicit reconstruction conditions for Lie\u2013Poisson systems and extend these results to the case where the symmetry group is a subgroup of the structure group of the configuration space.<\/p>\n<h3>C\u00e9dric M. Campos (Universidad de Valencia, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>The Tulczyjew\u2019s triple for Classical Field Theory [<a href=\"https:\/\/drive.google.com\/file\/d\/1TLGUJfwASnAZwDIg7wV_lf04a9TODS5N\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract<\/strong>: The Tulczyjew\u2019s triple associated with a fibration is introduced. For this purpose, a description of classical field theories of first order is presented.<br \/>The triple is adapted to the extended Hamiltonian formalism. Using this triple, we prove that Euler-Lagrange and Hamilton-De Donder-Weyl equations are the<br \/>local equations defining Lagrangian submanifolds of a premultisymplectic manifold.<\/p>\n<h3>Santiago Capriotti (Universidad Nacional del Sur, Argentina)<\/h3>\n<p><strong>Title:<\/strong> <em>Hamilton equations for gravity with basis [<a href=\"https:\/\/drive.google.com\/file\/d\/1tZmurZAu0G9iUL-nwAl_U74W9JwoaCHN\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> The vielbein formulation of gravity is a class of gravitational theories in which the metric and the connection are treated as independent variables. In this approach, the metric is introduced indirectly by means of a local frame on the tangent bundle. Consequently, one works with the frame bundle (and naturally associated bundles), and it is possible to set up a variational problem for gravity taking advantage of the geometrical structures present in these bundles. In a joint work with Guadalupe Quij\u00f3n, it was possible to develop a Hamiltonian version for this variational problem. This talk will present some of the features of that construction.<\/p>\n<h3>Matteo Dell\u2019Aqua (LMU, Germany)\u00a0<\/h3>\n<p><strong>Title:<\/strong> <em>On Disformal Transformations [<a href=\"https:\/\/drive.google.com\/file\/d\/1CzT-VVRmyPRvwLi2hb1ZY9YlltK9i617\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> Disformal transformations are non-natural transformations that relate some of the most prominent Modified Gravity theories, i.e. extensions of General Relativity that aim to model Dark Energy. Those transformations are geometrically interesting since they are not diffeomorphisms and relate systems of different order. In this talk, I will present preliminary results on the geometrical and physical implications of disformal-like transformations in mechanics. Particular attention will be paid to degrees of freedom, symmetries and dynamical equivalence. Work in progress with V. Errasti D\u00edez, J. Gaset Rif\u00e0 and M. Lainz Valc\u00e1zar.<\/p>\n<h3>Viviana Alejandra D\u00edaz (Universidad Nacional del Sur, Argentina)<\/h3>\n<p><strong>Title:<\/strong> <em>Lagrangian neural networks for nonholonomic mechanics [<a href=\"https:\/\/drive.google.com\/file\/d\/1HurajsNZVam3Dw8ZRoj2Lqvo0TK937vw\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> This talk presents an extension of Lagrangian Neural Networks (LNNs) to mechanical systems with nonholonomic constraints. LNNs provide a powerful framework for modeling physical systems, as they learn the system\u2019s Lagrangian and generate trajectories that nearly conserve energy. While previous studies have focused on unconstrained or holonomically constrained systems, here the methodology is adapted to handle nonholonomic restrictions. Classical benchmark examples illustrate that incorporating the constraints directly into the learning process improves trajectory prediction accuracy, enforces consistency with the nonholonomic constraints, and results in better energy behavior compared to unconstrained models.<\/p>\n<h3>Jordi Gaset Rif\u00e1 (CUNEF Universidad, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>From variational principles to geometry [<a href=\"https:\/\/drive.google.com\/file\/d\/1iLw7Z07KbEdJ6Zyl4SF3NYVlHqGpqUxS\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> A method to construct a geometric structure with the same solutions as a given variational principle is presented. The method applies to large<br \/>families of variational principles. In particular, the known results that assign cosymplectic geometry to Hamilton&amp;#39;s principle and cocontact geometry to Herglotz&amp;#39;s principle for regular Lagrangians are recovered. The unified Lagrangian-Hamiltonian formalism is also recovered via the absorption of the<br \/>holonomy conditions. The method is applied to singular action-dependent Lagrangians, which do not always lead to (pre)cocontact geometry. In these cases, the resulting geometry associated with the Herglotz&amp;#39;s variational principle is new.<\/p>\n<h3>Xavier Gr\u00e0cia (Universitat Polit\u00e8cnica de Catalunya, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>Time-dependent Riemannian metrics and connections [<a href=\"https:\/\/drive.google.com\/file\/d\/160p4soWynRUuF7-vrPOo0wQ7-m41SXzA\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> We study the notion of geodesics when a Riemannian metricdepends on the time parameter. This leads to the introduction of time-dependent covariant derivation operators, and the associated notion of<br \/>parallel transport.<\/p>\n<h3>Iv\u00e1n Guti\u00e9rrez Sagredo (Universidad de Burgos, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>Unimodularity and preservation of volume forms on Poisson-Lie groups and Poisson homogeneous spaces [<a href=\"https:\/\/drive.google.com\/file\/d\/1tqul158WlVvgvNE5fANwPM4fZc1vGGJn\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> In this talk I will introduce the notion of a Poisson-Lie (PL) group and a Poisson homogeneous space (PHS). Then I will briefly introduce Poisson cohomology (and in particular unimodularity) and its relation with the existence of preserved volume forms for Hamiltonian systems defined on PLs and PHSs. Moreover, under some assumptions, I will show how an infinitesimal characterisation can be given. I will illustrate all these results with some examples.<\/p>\n<h3>Rub\u00e9n Izquierdo L\u00f3pez (ICMAT, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>The graded Poisson bracket of general conservation laws in classical field <\/em><em>theories [<a href=\"https:\/\/drive.google.com\/file\/d\/12hFf_M2PNqHb9MY19RNDbQ3B7m1l1iOF\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract<\/strong>: In physics, the Noether correspondence between higher-form symmetries (symmetries parametrized by closed forms) and more general conservation laws (lower-degree forms that are closed on solutions) has attained importance in both classical and quantum theory. This correspondence is well known among physicists, but lacks a fully formalized mathematical framework. In this contribution, I will present a possible approach to the theory of general conservation laws in classical field theory using the graded Poisson brackets from multisymplectic geometry. I will emphasize on the duality between multivectors and forms and give some recent results regarding the algebra structure of Hamiltonian forms.<\/p>\n<h3>Mar\u00eda Jim\u00e9nez V\u00e1zquez (Universidad Carlos III, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>Equivariant Quantum Neural Networks: A groupoidal approach [<a href=\"https:\/\/drive.google.com\/file\/d\/1SAUKou7iAx-Yc9gSVFsMlRIc0nm3-FJb\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract<\/strong>: This talk introduces the theory of equivariant neural networks in both classical and quantum settings. Studying the geometry of the domains and<br \/>incorporating concepts such as symmetry and equivariance has significantly improved the efficiency and generalization of machine learning algorithms. We<br \/>present the general framework of this emerging field, often referred to as geometric deep Learning, and extend it to the quantum domain by employing a more abstract and foundational approach based on groupoid theory. This formulation establishes the theoretical underpinnings of equivariant quantum neural networks. Furthermore, we prove the Imprimitivity Theorem, which provides a one-to-one correspondence between representations of a groupoid and those of its isotropy groups.<\/p>\n<h3>Manuel Lainz (CUNEF, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>The groupoid of symmetries of a Hamiltonian system [<a href=\"https:\/\/drive.google.com\/file\/d\/1KRoccNnqgcUhekqIbVm8qYgyndjEcFMo\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> The jet groupoid of a manifold $\u03a0^1(MxM)$ is the set of invertible linear maps between its tangent spaces. A Hamiltonian system $(M, \\omega,H)$, induces several subgroups of the jet groupoid, by requiring the linear maps to preserve a combination of $\\omega, H, X_H$. We define these groupoids, compute their algebroids and interpret the A-connections. Flat and torsionless connections give rise to adapted coordinates. One important technical dificulty is that in most cases these subgroupoids fail to be manifolds, hece the algebroids are singular and fail to have constant rank. This is based on joint work with Victor M. Jim\u00e9nez.<\/p>\n<h3>\u00a0Asier L\u00f3pez-Gordon (Instytut Matematyczny PAN, Poland)<\/h3>\n<p><strong>Title:<\/strong> <em>Homogeneous Fronenius and Darboux theorems [<a href=\"https:\/\/drive.google.com\/file\/d\/1sbE75fkBWm42IIKOdstnKdm6T6KkD4gq\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> There are multiple situations in differential geometry and physics where a grading appears (the spin of particles, intensive\/extensive variables, the exterior product of differential forms, etc.). It is thus natural to seek coordinates which are simultaneously homogeneous (i.e. respecting the grading) and adapted to the geometric structure under consideration. I shall present a Frobenius theorem for involutive homogeneous distributions, as well as Darboux theorems for homogeneous presymplectic and Pfaffian forms. This is a joint work with Prof. J. Grabowski.<\/p>\n<h3>\u00a0Juan Manuel L\u00f3pez Medel (ICMAT, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>Discretization of Dirac structures [<a href=\"https:\/\/drive.google.com\/file\/d\/1kFOQneSf7FDFr8kgEJJ8QLiHmTnB26wV\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> We study the discretization of (almost-)Dirac structures using the notion of retraction and discretization maps on manifolds. Additionally, we apply the proposed discretization techniques to obtain numerical integrators for port-Hamiltonian systems and we discuss how to merge the discretization procedure<br \/>and the constraint algorithm associated to systems of implicit differential equations.<\/p>\n<h3>\u00c1lvaro Rodr\u00edguez Abella (Universidad Pontificia de Comillas, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>Safety filters for Large Language Models: A control theoretic approach to<\/em><br \/><em>toxicity prevention [<a href=\"https:\/\/drive.google.com\/file\/d\/1SbvBr-HZj4gZVTdkWWn7YrimtDDbkazG\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> The rapid integration of large language models (LLMs) into our everyday lives has outpaced safety considerations aimed at protecting users<br \/>from toxic outputs and preventing malicious actors from generating harmful text at scale. Our work addresses this issue by developing a framework for designing safety filters that preclude toxic outputs. To achieve this, we leverage Control Barrier Functions (CBFs) which enable the design of closed-<br \/>loop systems that remain safe. We consider the continuous-time model of an LLM, where tokens are regarded as the state of the model, and prove that by<br \/>only controlling the first token, any function satisfying mild assumptions becomes a CBF. Our approach can be utilized to design LLMs capable of<br \/>ensuring safety of its outputs without significantly affecting the original model\u2019s behavior.<\/p>\n<h3>Miguel Vaquero (ie University, Spain)<\/h3>\n<p><strong>Title:<\/strong> <em>Learning Hamiltonian Dynamics [<a href=\"https:\/\/drive.google.com\/file\/d\/1iR-45PvoTQTZAy1toOd6u--1vQZVCFul\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> Developing geometric integrators and geometry-aware learning paradigms are two complementary research directions in the study of dynamical systems. In this talk, we present recent advances that connect these areas by exploiting symplectic groupoids and Poisson geometry to learn Hamiltonian dynamics in a structure-preserving manner. We show how these geometric structures provide natural inductive biases for learning, allowing the resulting models to respect fundamental properties such as symplecticity, conservation laws, and invariants encoded by Poisson structures. This perspective leads to learning frameworks that are consistent with geometric integration theory and exhibit improved stability and long-time behavior when compared to unconstrained approaches.<\/p>\n<h3>Mats Vermeeren (Loughborough University, UK)<\/h3>\n<p><strong>Title:<\/strong> <em>Dual variables and variational principles for Hamiltonian PDEs [<a href=\"https:\/\/drive.google.com\/file\/d\/1EYKqn3d1xEs18dTQ3SrP7kGIvWo3LkxG\/view?usp=sharing\" target=\"_blank\" rel=\"noopener\">slides<\/a>]<\/em><\/p>\n<p><strong>Abstract:<\/strong> Does every Hamiltonian PDE have a Lagrangian formulation? We do<br \/>not claim a general answer to this question, but will give a strategy that appears quite effective in constructing variational principles for Hamiltonian PDEs.<br \/>It is well-known that in many cases (e.g. KdV equation) passing to a potential variable allows one to formulate a variational principle. We will show that such a potential variable can be thought of as an element of the dual space to the original phase space. We use this point of view to obtain a more general construction of variational principles for Hamiltonian PDEs. The same duality can also be observed in mechanics, but it is not the duality manifested in the Legendre transform. Instead it links the Hamiltonian formulation and the variational principle in phase space.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Plenary Speaker Paula Balseiro (UFF, Brazil) Title: \u00a0On conserved measures for nonholonomic systems with symmetries [slides]Abstract: One of the principal differences between Hamiltonian systems\u2014described on symplectic manifolds\u2014and nonholonomic systems is the existence of an invariant volume for the dynamics. However, &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"more-link\" href=\"https:\/\/wp.ull.es\/8ibmgmft\/programme\/\"> <span class=\"screen-reader-text\">PROGRAMME<\/span> Leer m\u00e1s \u00bb<\/a><\/p>\n","protected":false},"author":460,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"elementor_header_footer","meta":{"footnotes":""},"class_list":["post-26","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/pages\/26","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/users\/460"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/comments?post=26"}],"version-history":[{"count":2,"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/pages\/26\/revisions"}],"predecessor-version":[{"id":649,"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/pages\/26\/revisions\/649"}],"wp:attachment":[{"href":"https:\/\/wp.ull.es\/8ibmgmft\/wp-json\/wp\/v2\/media?parent=26"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}