Dr. Itamar Stein

Dr. Itamar Stein

 I am a lecturer at the mathematics unit of SCE

My main research interest is the representation theory of semigroups and categories

I try to find a combinatorial description of fundamental invariants of category algebras - mainly homological invariants

Another research interest is ordinary group representation theory. I am interested in combinatorial interpretation of branching rules for finite groups

I have also studied string rewriting systems, a topic in theoretical computer science

I have earned my Ph.D. in mathematics at Bar-Ilan university. My advisor was Prof. Stuart Margolis


Mathematics department


Decibel / 2015


2013-2017  Ph.D.  in Mathematics.  Bar-Ilan University, Israel. Dissertation title: Quivers and global dimension of monoid algebras.  Adviser: Prof. Margolis, S.     

2009-2012  M.Sc. (Summa cum Laude) in Mathematics. Bar-Ilan University, Israel.  Dissertation title: Graded monoids and graded monoid presentations.  Adviser: Prof. Margolis S.      

2004-2007  B.Sc. (Summa cum Laude) in Mathematics. Bar-Ilan University, Israel.      


Representation theory: Algebras of groups, semigroups and categories. Combinatorial and homological properties.

Semigroup theory: Ehresmann semigroups and their corresponding categories.

Algebraic combinatorics: Representation theory of finite groups. Branching rules.

Theoretical computer science: String rewriting systems. Decision problems and algorithms


Linear algebra


1.      Algebras of Ehresmann semigroups and categories. Semigroup Forum. Springer US, 2017. p. 509-526.

2.      The Littlewood-Richardson rule for wreath products with symmetric groups and the quiver of the category F≀FIn. Communications in Algebra 45.5 (2017): 2105-2126.

3.      The representation theory of the monoid of all partial functions on a set and related monoids as EI-category algebras. Journal of Algebra 450 (2016): 549-569.

4.      Reducing the gradedness problem of string rewriting systems to a termination problem. RAIRO-Theoretical Informatics and Applications 49.3 (2015): 233-254.