Winter semester 2025/2026
October 6h - Triangulated categories, (co)homological functors, representable functors.
Relevant literature:
A. Neeman, Triangulated Categories.
D. Murfet, Triangulated Categories, Link
October 13th - Examples triangulated categories: Stable module category, stable homotopy category, derived category.
Relevant literature:
October 20th - Products of triangles via pre-triangles, detection of iso/mono/epi-morphisms/non-functoriality of mapping cones.
Relevant literature:
October 27th - Homotopy colimits.
Relevant literature:
D. Murfet, Triangulated Categories, Link
November 3rd - Functor category, restricted Yoneda embedding
Relevant literature:
Summer semester 2024/2025
February 24th - Linear topological rings, finite topology on endomorphism rings.
Relevant literature:
March 3rd - Complete and separated linear topological rings.
Relevant literature:
March 10th - Endomorphism ring is complete, "Complete free modules" over complete linear rings, monadic definition of modules.
Relevant literature:
Leonid Positselski, Contramodules, Link - Subsection 2.1.
March 17th - Definition of a contramodule, some basic properties of the category of contramodules.
Relevant literature:
March 24th - Abstract properties of the category of contramodules.
Relevant literature:
Leonid Positselski, Contramodules, Link - Subsection 2.1.
Jan Šťovíček and Leonid Positselski, The tilting-cotilting correspondence, Link - Sections 6.2 & 6.3
Leonid Positselsky and Jiří Rosická, Covers, envelopes, and cotorsion theories in locally presentable abelian categories and contramodule categories, Link - Section 5.
Leonid Positselsky, Answer to the following question at Mathoverflow, Link.
Locally presentable categories on nLab, Link.
Adjoint functor theorem on nLab, Link.
March 31th - Cocomplete categories a with projective generator, equivalence between Add(M) and Proj(Ctra-End(M)).
Relevant literature:
Jan Šťovíček and Leonid Positselski, The tilting-cotilting correspondence, Link - Sections 6.3 & 7.1
April 7th - category of discrete modules, contratensor product.
Relevant literature:
April 14th - fullness of the forgetful functor from contramodules to modules.
Relevant literature:
Jan Šťovíček and Leonid Positselski, The tilting-cotilting correspondence, Link - Theorem 6.10, Section 7.3
Jan Šťovíček and Leonid Positselski, Topologically semisimple and topologically perfect topological rings, Link - Corollary 4.4, Section 5
Leonid Positselski, Homological algebra of semimodules and semicontramodules: Semi-infinite homological algebra of associative algebraic structures, Link - Subsection A.1.2--- A counterexample to fullness of the forgetful functor
Leonid Positselski, Homological full-and-faithfulness of comodule inclusion and contramodule forgetful functors, Link - Example 7.2 --- Another counterexample to fullness of the forgetful functor
April 28th - The heart of a tilting module as a contramodule category, counterexample for a tilting complex
Relevant literature:
May 5th - Abelianization, restricted Yoneda embedding
Relevant literature:
Jan Šťovíček and Leonid Positselski, The tilting-cotilting correspondence, Link - Theorem 7.1
-, Topological endomorphism rings of tilting complexes, Link - Section 2
Daniel Murfet, Rings with Several Objects, Link
Henning Krause, Smashing subcategories and the telescope conjecture – an algebraic approach, Link
Amnon Neeman, Triangulated Categories, Chapters 5 and 6
May 12th and last - definable subcategories, derived topological Morita theory
Relevant literature:
-, Topological endomorphism rings of tilting complexes, Link - Section 4,5,6/li>
R. Göbel and J. Trlfaj, Approximations and Endomorphism Algebras of Modules, Section 13 and 15
Winter semester 2024/2025
October 14th - An overview of Morita theory, derived Morita theory, and the direction of the seminar.
Relevant literature:
October 21th - No seminar.
October 28th - No seminar.
November 4th - Derived category of a hereditary abelian category, tilting modules over hereditary rings, example over the quiver A3.
Relevant literature:
November 11th - An example of non-classical tilting module over the integers, proof that the representable functor is fully faithful.
Relevant literature:
November 18th - T-structures in triangulated categories, the heart of a t-structure is abelian and induces a cohomological functor.
Relevant literature:
November 25th - Realization functors, effacability, basics on abstract silting objects.
Relevant literature:
December 2nd - Abstract tilting theorem, compact tilting objects.
Relevant literature:
C. Psaroudakis, J. Vitória, Realisation functors in tilting theory, Link - Section 5
December 9th - I'm not here!
December 16th - Abstract Morita theorems for large and bounded tilting and cotilting complexes of R-modules.
Relevant literature:
January 6th - Example computed: The divisible tilting module over the integers, foreshadowing of contramodules.