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</o:shapelayout></xml><![endif]--></head><body lang=SL link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><img width=1058 height=295 style='width:11.025in;height:3.075in' id="Picture_x0020_1" src="cid:image001.png@01DA00D6.2A714A80"><o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'>Vabimo vas na 6. predavanje iz sklopa »Kolokviji na IJS« v akademskem letu 2023/24, ki bo <b>v sredo, 6.</b> <b>decembra 2023, ob 13:00</b> v Veliki predavalnici Instituta »Jožef Stefan« na Jamovi cesti 39 v Ljubljani. Predavanje bo <b>v angleščini</b>. Na voljo bodo kava, pijača in prigrizki.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><b><span lang=EN-US style='font-size:16.0pt'>Fizika na robu kaosa</span></b><b><span style='font-size:16.0pt'><o:p></o:p></span></b></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><span style='font-size:16.0pt'><o:p> </o:p></span></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><b><u><span lang=EN-US style='font-size:12.0pt'>izr. prof. dr. Lev Vidmar</span></u></b><b><u><span style='font-size:12.0pt'><o:p></o:p></span></u></b></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><i>Institut »Jožef Stefan« in Fakulteta za matematiko in fiziko, Univerza v Ljubljani, Slovenija<o:p></o:p></i></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'>Zadnjih nekaj desetletij raziskav je ključno prispevalo k razumevanju, kako se interagirajoči kvantni sistem, ki je izoliran od okolice, po vzbuditvi spet približa termičnemu ravnovesju. Ta proces imenujemo termalizacija, za stanje sistema pa pravimo, da je ergodično. Mehanizem termalizacije danes razumemo skozi hipotezo, da je vsako lastno stanje hamiltonke termalno že samo zase, kar je posledica mnogodelčnega kvantnega kaosa. Pod katerimi pogoji pa se lahko zgodi, da fizikalni sistem ne termalizira, da torej ni kaotičen in se mu ne more pripisati temperature? V zadnjem desetletju smo bili priča intenzivnim raziskavam tega vprašanja v kvantnih sistemih z velikim številom delcev. Osrednji motiv teh raziskav je iskanje nove vrste kvantnih faznih prehodov, ki jih opišemo kot prehode iz ergodične v neergodično fazo snovi. V predavanju bom opisal nekatere njihove lastnosti in podal primere raziskav, ki bodo morda vodili v novo razumevanje teh prehodov.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><b>O predavatelju</b>: Lev Vidmar je izredni profesor za področje fizike na Univerzi v Ljubljani in višji znanstveni sodelavec na Institutu »Jožef Stefan«. Pred kratkim je prejel Blinčevo nagrado za fizike na začetku kariere in pridobil prestižni projekt Evropskega raziskovalnega sveta (ERC).<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><span style='font-size:10.0pt'>Napovednik predavanja in posnetke preteklih predavanj najdete na <b>novi spletni strani »Kolokvijev na IJS«</b> </span><a href="https://kolokviji.ijs.si/"><span style='font-size:10.0pt'>https://kolokviji.ijs.si/</span></a><span style='font-size:10.0pt'>, posnetke pa tudi posebej na </span><a href="https://video.arnes.si/?hashtag=Kolokviji_IJS"><span style='font-size:10.0pt'>https://video.arnes.si/?hashtag=Kolokviji_IJS</span></a><span style='font-size:10.0pt'> (zadnje tri sezone) in </span><a href="http://videolectures.net/kolokviji_ijs"><span style='font-size:10.0pt'>http://videolectures.net/kolokviji_ijs</span></a><span style='font-size:10.0pt'> (starejši).<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'>______________<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'>We invite you to the 6th lecture in the framework of »JSI Colloquia« in the academic year 2023/24, which will take place on <b>Wednesday, December 6, 2023, at 1:00 PM</b> in the main lecture hall of Jožef Stefan Institute, Jamova cesta 39 in Ljubljana. The lecture will be held <b>in English</b>. Coffee, drinks and snacks will be available.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><b><span style='font-size:16.0pt'>Physics at the edge of chaos<o:p></o:p></span></b></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><span style='font-size:16.0pt'><o:p> </o:p></span></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><b><u><span style='font-size:12.0pt'>Izr. prof. dr. Lev Vidmar<o:p></o:p></span></u></b></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><i>Jožef Stefan Institute and Faculty of Mathematics and Physics, University of Ljubljana, Slovenia<o:p></o:p></i></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'>Recent decades of research contributed significantly to our understanding how an interacting quantum system, evolving in isolation from environment, approaches a thermal equilibrium. This process is called thermalization, and the state of the system is referred to as being ergodic. The mechanism of thermalization is today understood via the eigenstate thermalization hypothesis stating that all eigenstates of a Hamiltonian are already thermal, which is a consequence of many-body quantum chaos. Under what conditions can a physical system not thermalize, that is, not be chaotic and cannot be attributed a temperature? This question has been intensively studied in the last decade in many-body quantum systems. The main motivation of these studies is to establish a new type of quantum phase transitions dubbed ergodicity breaking phase transitions. I will describe some of their properties and provide examples of recent studies that may lead to a new understanding of these transitions.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><b>About the lecturer</b>: Lev Vidmar is an associate professor of physics at the University of Ljubljana and a senior scientific associate at the Jožef Stefan Institute. Recently, he received the Blinc Prize for early-career physicists and obtained a prestigious project from the European Research Council (ERC).<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><span style='font-size:10.0pt'>The lecture trailer and recordings of past lectures can be found on the <b>new website of »JSI colloquia«</b></span> <a href="https://kolokviji.ijs.si/"><span style='font-size:10.0pt'>https://kolokviji.ijs.si/</span></a><span style='font-size:10.0pt'>, and recordings specifically at </span><a href="https://video.arnes.si/en/?hashtag=Kolokviji_IJS"><span style='font-size:10.0pt'>https://video.arnes.si/en/?hashtag=Kolokviji_IJS</span></a><span style='font-size:10.0pt'> (last three seasons) and </span><a href="http://videolectures.net/kolokviji_ijs"><span style='font-size:10.0pt'>http://videolectures.net/kolokviji_ijs</span></a><span style='font-size:10.0pt'> (older).<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0cm;line-height:normal'><o:p> </o:p></p></div></body></html>