I am an associate professor at the Department of Algebra at Charles University in Prague.
Contact
Email: shaul at karlin.mff.cuni.cz

Publications
- Formalization in Lean of faithfully flat descent of projectivity. Code. 2026, Submitted.
- Openness with respect to levels in triangulated categories. With Souvik Dey and Jian Liu. 2025. Submitted.
- “Differential graded rings and their applications” – Habilitation thesis. Approved, 2025.
- Gorenstein acyclic complexes and finitistic dimensions. 2023. Submitted.
- Acyclic complexes of injectives and finitistic dimensions. With an appendix by Tsutomu Nakamura and Peder Thompson. 2023. Submitted.
- Categorical properties of reduction functors over non-positive DG-rings. Proceedings of the AMS 152 (2024), 489-500.
- The finitistic dimension conjecture via DG-rings. 2022. Submitted.
- Finitistic dimensions over commutative DG-rings. With Isaac Bird, Prashanth Sridhar and Jordan Williamson. Mathematische Zeitschrift (2025) 309, no.1, Paper No. 3.
- Sequence-regular commutative DG-rings. Journal of Algebra 647, 1 June 2024, Pages 400-435(2024).
- Lifting (co)stratifications between tensor triangulated categories. With Jordan Williamson. Israel Journal of Mathematics Volume 261, pages 249–280, (2024).
- Open loci results for commutative DG-rings. Journal of Pure and Applied Algebra 226 (2022), no. 5, Paper No. 106922.
- Koszul complexes over Cohen-Macaulay rings. Advances in Mathematics, Volume 386, 6 August 2021.
- Smooth flat maps over commutative DG-rings. Mathematische Zeitschrift (2021) 299:1673–1688
- Pole placement for overdetermined 2D systems. With Victor Vinnikov. Linear Algebra and Its Applications 610 (2021) pp. 529-559.
- The Cohen-Macaulay property in derived commutative algebra. Transactions of the AMS 373 (2020), no. 9, 6095–6138.
- Completion and torsion over commutative DG rings. Israel Journal of Mathematics, , Volume 232, Issue 2, pages 531–588.
- Injective DG-modules over non-positive DG-rings. Journal of Algebra 515 (2018) pp. 102-156
- Homological dimensions of local (co)homology over commutative DG-rings. Canadian Mathematical Bulletin 61(2018), no. 4, 865-877
- Tensor product of dualizing complexes over a field. J. Commut. Algebra, Volume 10, Number 2 (2018), 243-263.
- Adic reduction to the diagonal and a relation between cofiniteness and derived completion. Proceedings of the AMS, Volume 145, Number 12, December 2017, Pages 5131-5143.
- The twisted inverse image pseudofunctor over commutative DG rings and perfect base change. Advances in Mathematics, Volume 320, 7 November 2017, Pages 279-328.
- Hochschild cohomology commutes with adic completion. Algebra & Number Theory 10-5 (2016), 1001-1029.
- Relations between derived Hochschild functors via twisting. Communications in Algebra 44:7 (2016), 2898-2907.
- Reduction of Hochschild cohomology over algebras finite over their center. Journal of Pure and Applied Algebra 219 (2015), 4368-4377.
- Cohomologically Cofinite Complexes. With Marco Porta and Amnon Yekutieli. Communications in Algebra Volume 43, Issue 2, 2015.
- On the Homology of Completion and Torsion. With Marco Porta and Amnon Yekutieli. Algebras and Representation Theory February 2014, Volume 17, Issue 1, pp 31-67. Errata.
- Completion by Derived Double Centralizer. With Marco Porta and Amnon Yekutieli. Algebras and Representation Theory April 2014, Volume 17, Issue 2, pp 481-494.
Conference proceedings
- Tensor product of dualizing complexes over a field. In: Herbera D., Pitsch W., Zarzuela S. (eds) Extended Abstracts Spring 2015. Trends in Mathematics, vol 5. Birkhäuser, Cham
- Towards coherent duality over derived formal schemes – “Hochschild Cohomology in Algebra, Geometry, and Topology”, 2016, Oberwolfach reports.
- State feedback for overdetermined 2D systems: pole placement for bundle maps over an algebraic curve. With Victor Vinnikov. International Workshop on Multidimensional (nD) Systems, IEEE, 2009
Teaching
In the 2025/2026 winter semester I teach a course on Homological algebra and a course on Algebraic Geometry.
Grants
I was the principal investigator of the grant “Cohen-Macaulay rings and their applications in higher algebra and topology“.
Student supervision
PhD students
- Jindřich Novák (since October 2025).
Master students supervised
- Enrico Sabatini (graduated 2022, joint supervision with Prof. Jorge Nuno Dos Santos Vitória).
- Jindřich Novák (graduated 2025).
- Alžběta Kocmanová (since October 2025).
Bachelor thesis supervised
- Edward Young (graduated 2023).
- Emil Čuřín (graduated 2024).
Conferences
In Februrary 2020 I organized the conference Derived Categories.
Past positions
Before coming to Prague, I was a postdoctoral researcher at Bielefeld, Germany, hosted by Prof. Henning Krause, at Antwerp, Belgium, hosted by Prof. Wendy Lowen, at the Weizmann institute, Israel, and at Ben-Gurion university of the Negev. I graduated from Ben-Gurion at 2013. My PhD advisor was Prof. Amnon Yekutieli.