<!DOCTYPE html><html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /></head><body><div data-html-editor-font-wrapper="true" style="font-family: arial, sans-serif; font-size: 13px;">Hola,<br><br>Les recuerdo que esta tarde es la jornada de dinámica en superficies a partir de las 14:00 en el IMERL.<br><br>Saludos<br><br><br>22 de febrero de 2023 16:49, <a target="_blank" tabindex="-1" href="mailto:smartinchich@cmat.edu.uy">smartinchich@cmat.edu.uy</a> escribió:<br> <blockquote><div><div><div style="font-family: arial, sans-serif;font-size: 13px"><div><div><div style="font-family: arial, sans-serif;font-size: 13px"><div><div><div style="font-family: arial, sans-serif;font-size: 13px"><div><div><div style="font-family: arial, sans-serif;font-size: 13px"> <p><signature></signature><span style="color: rgb(34, 34, 34);font-family: Arial, Helvetica, sans-serif;font-size: small;font-style: normal;font-variant-ligatures: normal;font-variant-caps: normal;font-weight: 400;letter-spacing: normal;orphans: 2;text-align: start;text-indent: 0px;text-transform: none;white-space: normal;widows: 2;word-spacing: 0px;-webkit-text-stroke-width: 0px;background-color: rgb(255, 255, 255);text-decoration-thickness: initial;text-decoration-style: initial;text-decoration-color: initial;display: inline !important;float: none">Hola,</span><br><br><span style="color: rgb(34, 34, 34);font-family: Arial, Helvetica, sans-serif;font-size: small;font-style: normal;font-variant-ligatures: normal;font-variant-caps: normal;font-weight: 400;letter-spacing: normal;orphans: 2;text-align: start;text-indent: 0px;text-transform: none;white-space: normal;widows: 2;word-spacing: 0px;-webkit-text-stroke-width: 0px;background-color: rgb(255, 255, 255);text-decoration-thickness: initial;text-decoration-style: initial;text-decoration-color: initial;display: inline !important;float: none">El <strong>lunes 27/02</strong> a partir de las <strong>14:00</strong> en el <strong>Salón de seminarios del IMERL</strong> (salón 101) tendremos una tarde dedicada a la dinámica en superficies, con dos charlas impartidas por líderes del área.<br><br><br>La primera:</span><br><br>Fabio Tal (Universidade de São Paulo)<br><br>Title : Rotational chaos for surface dynamics<br><br>Abstract: We study homeomorphisms of surfaces,with emphasys the annulus, trying to characterize when the associated dynamical system has positive topological entropy in the presence of points having different rotation numbers. We describe some previous results and we show that any homeomorphism of the annulus having an invariant circloid with a non-trivial rotation set has positive entropy, a result conjectured in the 90s.</p> <div style="color: rgb(34, 34, 34);font-family: Arial, Helvetica, sans-serif;font-size: small;font-style: normal;font-variant-ligatures: normal;font-variant-caps: normal;font-weight: 400;letter-spacing: normal;orphans: 2;text-align: start;text-indent: 0px;text-transform: none;white-space: normal;widows: 2;word-spacing: 0px;-webkit-text-stroke-width: 0px;background-color: rgb(255, 255, 255);text-decoration-thickness: initial;text-decoration-style: initial;text-decoration-color: initial">Joint with A. Passeggi<br><br><br>La segunda:<br><br>Patrice Le Calvez (Sorbonne Université)<br><br>Titre : The Calabi invariant of an irrational pseudo rotation; a finite dimensional approach.<br><br>Abstract : Some years ago, Michael Hutchings proved that the Calabi invariant of an irrational pseudo rotation of the disk is equal to its rotation number. The proof uses Embedded Contact Homology theory. We give a proof that uses finite dimensional arguments, related to the dynamical study of the gradient field of a generating function.<br><br><br>Saludos</div> <signature></signature> </div></div></div></div></div></div></div></div></div></div></div></div></blockquote> <signature></signature><br> </div></body></html>