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Уважаемые коллеги!<br>
<br>
В пятницу 12 ноября в 11:30 состоится коллоквиум с докладом:<br>
<br>
John Chalker (Physics Department, University of Oxford)<br>
<font size="4"><b>Many-body delocalisation as symmetry breaking</b></font><br>
<br>
<div class="abstract tex">
I will start this talk with an overview of recent work on quantum
dynamics in many body systems far from equilibrium. This work has
led to an understanding from the
perspective of quantum information, of how a such systems may
approach an
equilibrium state at long times, in which initial conditions are
effectively forgotten. It
has also led to an appreciation that there are classes of system
in which an
equilibrium state is not reached at long times. One of these
classes is made up of
many-body localised systems, in which randomness in the
Hamiltonian is
responsible for a long-lived memory of the initial state of a
system. By varying the
strength of randomness, a transition can be induced between
localised and ergodic
phases, which seems very different from conventional
symmetry-breaking phase
transitions. <br>
In the second part of the talk I will discuss minimal models for
quantum chaos and
many-body localisation. The models are Floquet quantum circuits
for lattice spin
systems, in which time evolution is generated by unitary gates
that couple
neighbouring sites. In particular, I will examine the
circumstances in which a version
of the so-called diagonal approximation (originally developed for
the semiclassical
limit in low-dimensional chaotic systems) can be applied to these
systems. Within
this framework I will show that the many-body delocalisation
transition can be seen
as a form of symmetry breaking transition, having many of the
features generally
associated with conventional phase transitions in classical
statistical mechanical
models. <br>
</div>
<br>
ID и пароль онлайн-трансляции в Zoom те же, что и для предыдущих
трансляций докладов на Ученом совете:<br>
<div class="moz-cite-prefix"> <a class="moz-txt-link-freetext"
href="https://zoom.us/j/96899364518?pwd=MzBsR2lYT0lYL2x2b1oyNU9LeWlWUT09">https://zoom.us/j/96899364518?pwd=MzBsR2lYT0lYL2x2b1oyNU9LeWlWUT09</a><br>
Meeting ID: 968 9936 4518<br>
Пароль: 250319 </div>
<br>
Для приезда в Институт можно воспользоваться автобусом, который
будет организован по записи при числе желающих не менее 5. <br>
Для записи на автобус из Москвы в Черноголовку необходимо до 18:00
четверга отправить письмо на адрес электронной почты <a class="moz-txt-link-abbreviated" href="mailto:bus@itp.ac.ru">bus@itp.ac.ru</a>.
После этого записавшимся до 20:00 поступит подтверждение об отправке
или неотправке автобуса в зависимости от числа записавшихся. <br>
Запись на обратный автобус - как и раньше на Ученом совете.<br>
<br>
<br>
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