News archive


Algebra seminar - September 19, 1pm, lecture room M5 PDF Print

We will continue on Thursday, September 19, in M5 at 1pm by the talk

J. Adamek

Ultrafilters in Locally Presentable Categories

Abstract:
For a number of locally finitely presentable categories K we describe the codensity monad of the full embedding of all finitely presentable objects into K. We introduce the concept of D-ultrafilter on an object, where D is a “nice” cogenerating object of K.
Example: in Pos we choose the 2-chain as D. A D-ultrafilter on a poset X is a prime up-set, closed under finite intersecitions, in the poset of all up-sets of X.

We prove that the above codensity monad assigns to every object an object representing all D-ultrafilters on it. Our result covers e.g. the categories of sets, vector spaces, posets, semilattices, graphs and M-sets for finite commutative monoids M.

Last Updated on Monday, 16 September 2019 09:30
 
25th mathematical hike - September 28th 2019 PDF Print

Dear Friends of Hikes and Mathematics,

you are invited to our 25th mathematical hike planned on September 28th. Start at 09:44 at the train station "Níhov". There is a train from Brno that leaves the station "Dolní nádraží" at 08:50.

We have planned a 16 km hike from Níhov to Tišnov regardless of the weather. We follow yellow and green paths, also we can visit the abbey "Porta coeli".

We would love to see you there, please join us. It's a great opportunity for a meeting of students, graduates and employees of our department of all age or mathematical categories.

We are planning our next hikes on 2nd of November, 14th of December.

All information and photos can be found at http://conference.math.muni.cz/vylety/. (in CZ)

Have a nice start of the semester. Looking forward to see you soon,

Jonatan Kolegar and Jana Bartoňová, organizers,
Jan Slovák, Director of the Department of Mathematics and Statistics

Last Updated on Friday, 13 September 2019 08:07
 
24th mathematical hike - July 19th 2019 PDF Print

Extreme hike! You are invited to our 24th mathematical hike, planned on Friday 19th of July. The destination is a point in time and space the next day, expect a 30 km walk through night and darkness. Meeting point 49.1941725N, 16.6594683E at 20:37.

Have a nice summer,

Jonatan Kolegar a Jana Bartoňová, organizers,
Jan Slovák, Director of the Department of Mathematics and Statistics

Last Updated on Friday, 21 June 2019 14:23
 
Differential equations seminar - June 12, 11am, seminar room on the 1st floor PDF Print

Seminar of differential equations will continue on June 12, 2019 at 11am in seminar room on the 1st floor.

prof. Stephen L. Clark (Missouri University of Science and Technology)

Krein's Formula and Sturm-Liouville Operators on a Compact Interval

Abstract:
Recalling parametrizations of self-adjoint extensions associated with a regular, symmetric, second-order differential expressions, we give a comprehensive accounting of all self-adjoint extensions of the minimal Sturm--Liouville operator in terms of Krein's formula for resolvent differences given Sturm--Liouville operators with Dirichlet boundary conditions at a and b as a convenient reference operator, and give a detailed description of the Krein extension of the minimal Sturm--Liouville operator.

Last Updated on Monday, 10 June 2019 10:07
 
Algebra seminar - May 30, 1pm, lecture room M5 PDF Print

We will continue on Thursday, May 30, in M5 at 1pm by the talk

M. Lieberman

Cofibrant generation and stable independence

Abstract:
We discuss recent joint work with Rosicky and Vasey concerning connections between stable independence notions and cofibrant generation of weak factorization systems in locally finitely presentable categories. In particular, we show that for a sufficiently nice class of morphisms M in an lfp category K, M is cofibrantly generated just in case the wide subcategory of K with morphisms precisely those in M has a stable independence relation. This result, and its consequences, cover a wide variety of examples and, in particular, provide an ideal context in which to analyze the stability of Ext-orthogonality classes of models of the sort considered in Baldwin/Eklof/Trlifaj.

Last Updated on Thursday, 23 May 2019 07:34
 
«StartPrev21222324252627282930NextEnd»

Page 30 of 50