Free idempotent generated semigroups and endomorphism monoids of free $G$-acts

Igor Dolinka, Victoria Gould, Dandan Yang

The study of the free idempotent generated semigroup $\mathrm{IG}(E)$ over a biordered set $E$ began with the seminal work of Nambooripad in the 1970s and has seen a recent revival…