January 16, 12:00-13:00, Seminar room 209, Manchester building.
Abstract: I plan to show a proof of the statement "residually-finite-by-residually-finite extensions are weakly sofic". The proof is based on characterization of weakly sofic groups by solvability of equations over groups. It looks different from other proofs of soficity and weak soficity. I plan to discuss relations of equations on and over groups with soficity in some details.