nLab Tomasz Maszczyk

Tomasz Maszczyk is a Polish mathematician (Warsaw University and IMPAN) with main interests in algebraic geometry, noncommutative algebra and noncommutative geometry (both of algebraic and of operator-algebraic flavour). With Piotr Hajac, he coordinates a weakly active seminar in Warsaw on noncommutative geometry at IMPAN, frequently featuring international leading experts in noncommutative geometry.

Maszczyk created an original viewpoint and approach to noncommutative geometry based on monoidal abelian categories viewed as categories of quasicoherent sheaves. Galois and reconstruction theorems of various sort (Tannakian, Morita-type…), and remarkable and consistent application of categorical thinking (neglected by most of the mainstream schools in noncommutative geometry), play role at many places in his work. His works gave light to a number of problems related to cyclic homology, corings, Hopf-Galois extensions, descent theory and mathematics of regular differential operators in commutative and noncommutative algebraic geometry.

Most of Maszczyk’s main program is still unpublished (even on arXiv). Among his articles on the arXiv cf.

For an anouncement of some unpublished interesting results see the following abstract

T. Maszczyk, NCG Seminar IMPAN 18 Feb 2008


According to Grothendieck-Galois theory, there is a close relation between splittings of commutative rings by an appropriate base change and (groupoid) actions. The reconstruction of the action from a given splitting is called the Galois reconstruction. According to Grothendieck-Deligne-Saavedra Rivano-Tannaka theory, there is another close relation between representations of a given groupoid and the groupoid itself. The reconstruction of the groupoid from its representations is called the Tannaka reconstruction. We show that both reconstructions are particular cases of our theorem about splittings of flat covers in the bicategory of monoidal categories.

  • Hochschild cohomology, Entropy and information theory.

Tomasz Maszczyk has also developed a cohomological theory of Entropy based on Hochschild cohomology. It is related to the information cohomology of Baudot-Bennequin.

The link to the abstract of this talk is below.

Hochschild cohomology and Shannon entropy

Here is the link to Tomasz Maszczyk’s homepage.

category: people

Last revised on December 3, 2022 at 12:24:41. See the history of this page for a list of all contributions to it.