Dear all,
This week we begin this semester's noon seminar series. Our first
speaker on Thursday 24 Feb is Tomas Juškevičius (Czech Academy of
Sciences). Please find the title and abstract attached below.
For more information on the upcoming noon lectures, please visit
https://www.mff.cuni.cz/en/kam/teaching-and-seminars/noon-lectures
With best regards,
Misha.
--------------------------------------
Anticoncentration of sums of random vectors: on conjectures of
Leader-Radcliffe and Lee Jones
Tomas Juškevičius
Czech Academy of Sciences
February 24, 2022, 12:20 in S6
Abstract
In this talk we shall address the topic anticoncentration inequalities
for sums of random vectors. In particular, we shall asymptotically
establish two conjectures: one by Lee Jones (1978) and another by
Leader-Radcliffe (1994). Perhaps surprisingly, the essential ingredient
to establish the latter result is the Strong Perfect Graph Theorem by
Chudnovsky, Robertson, Seymour and Thomas (2002). The talk is based on
recent joint work with V. Kurauskas (Vilnius University).
----------------------------------------
Dear Colleagues,
let me to invite you to 122. Mathematical Colloquium - prof. Alexander
Scott
(on this Thursday 2.2.2023)
____________________________________________________________________
122. kolokvium:
GRAPHS OF LARGE CHROMATIC NUMBER
A. D. Scott
ctvrtek 2. unora 2023 ve 14:00, aula (refektar), prvni patro
MFF UK, Malostranske nam. 25, Praha 1
____________________________________________________________________
Abstract.
The chromatic number has been a~fundamental topic of study in graph theory
for more than 150 years. Graph colouring has a~deep combinatorial theory
and, as with
many NP-hard problems, is of interest in both mathematics and computer
science. An
important challenge is to understand graphs with very large chromatic
number. The
chromatic number tells us something global about the structure of a
graph: if $G$ has
small chromatic number then it can be partitioned into a~few very simple
pieces. But
what if $G$ has large chromatic number? Is there anything that we can
say about its
local structure? In particular, are there particular substructures that
it must
contain? In this talk, we will discuss recent progress and open problems
in this area.
________________________________________________________________________
(pdf pozvanky: https://kam.mff.cuni.cz/~klazar/scott.pdf)
Dear Colleagues,
we invite you to the next meeting of Prague Computer Science Seminar
*** on this Thursday, January 12th, at 4:15 pm ***
at MFF UK building
*** Malostranské náměstí 25, Lecture room S5 ***
The talk is
Pavel Ircing & Jan Švec: Searching Large Audiovisual Archives
more information is available at https://www.praguecomputerscience.cz/
Kind regards,
Petra Milštainová
on behalf of organizers of Prague Computer Science Seminar
--
Petra Milštainová
tel: +420 951 554 324
Univerzita Karlova
Matematicko-fyzikání fakulta UK
Informatický ústav Univerzity Karlovy
Malostranské nám. 25
118 00 Praha 1
Dear Colleagues,
we invite you to the next meeting of Prague Computer Science Seminar -
first in new year 2023
*** on Thursday, January 12th, at 4:15 pm ***
at MFF UK building
*** Malostranské náměstí 25, Lecture room S5 ***
The talk is
Pavel Ircing & Jan Švec: Searching Large Audiovisual Archives
more information is available at https://www.praguecomputerscience.cz/
Kind regards,
Petra Milštainová
on behalf of organizers of Prague Computer Science Seminar
--
Petra Milštainová
tel: +420 951 554 324
Univerzita Karlova
Matematicko-fyzikání fakulta UK
Informatický ústav Univerzity Karlovy
Malostranské nám. 25
118 00 Praha 1
Dear Colleagues,
let me to send a reminder for 5.1.2023 - prof. Ehud Hrushovski - 121.
Mathematical Colloquium
____________________________________________________________________
121. kolokvium:
ELEMENTARY RAMSEY THEORY, APPROXIMATE SUBGROUPS
AND A MODEL-THEORETIC GALOIS GROUP
E. Hrushovski
ctvrtek 5. ledna 2023 ve 14:00, aula (refektar), prvni patro
MFF UK, Malostranske nam. 25, Praha 1
____________________________________________________________________
Abstract.
A structure has the "elementary Ramsey property"
if any colouring, restricted to a subset that
approximates the full structure to a prescribed degree,
becomes definable. The
word elementary refers to the fact that it is really a property of the
first-order
theory, rather than the structure. This slight variation on structural
Ramsey
theory allows the following theorem: any theory T has
a canonical minimal expansion T^{ram} to one with the elementary Ramsey
property. It is a soft result in a hard field, but has the virtue of
bringing out
a hidden automorphism group, namely the automorphism group of T^{ram}
over T. In the case of Ramsey's original theorem, the theory is that of
a structureless set, the expansion consists of a linear
ordering < (thus an ordering is not merely an artefact of the proof!),
and the group is the two-element group exchanging < and its opposite
ordering >.
Evans, Hubička and Nešetřil have previously shown that such a theorem is not
possible in a more usual (aleph_0-categorical) framework of structural
Ramsey theory.
This construction is a special case of a canonical group construction
with a long history in model theory, going back to many including
Krupinski, Pillay, Lascar, Shelah, Galois. In another
setting it provides a locally compact group
associated with an approximate subgroup of any group, and
leads to a general classification of approximate subgroups.
I will define these various notions in the talk and try to explain
their relationship.
-------------------------------------------------------------------------------------
(pdf pozvanky - obsahuje laudatio a dalsi informace o kolokviich:
https://kam.mff.cuni.cz/~klazar/hrush.pdf)
--
Petra Milštainová
tel: +420 951 554 324
Univerzita Karlova
Matematicko-fyzikání fakulta UK
Informatický ústav Univerzity Karlovy
Malostranské nám. 25
118 00 Praha 1