Critical CoHAs, vertex coalgebras and Deformed Drinfeld coproducts

Shivang Jindal, Sarunas Kaubrys, Alexei Latyntsev

We construct a vertex coproduct on the Kontsevich--Soibelman cohomological Hall algebra (CoHA) of a quiver with potential, following Joyce (2018). We show it forms a vertex bialgeb…