I'm looking for a reference for the answer to the following questions.
Let $X$ be an algebraic variety. When is the cup product a morphism of Mixed Hodge structures? Does $X$ have to be smooth?
I'm looking for a reference for the answer to the following questions.
Let $X$ be an algebraic variety. When is the cup product a morphism of Mixed Hodge structures? Does $X$ have to be smooth?