It's somewhat common in set notations to use * and + for set union and set intersection for very similar reasons. Some programming languages even use that in their type language (a union of two types is A * B and an intersection is A + B).
Interestingly, this is why Category Theory in part exists to describe the similarities between operators in mathematics such as how * and ∧ contrast/are similar. Category Theory gets a bad rap for being the origin of monads and fun phrases like "monads are a monoid in the category of endofunctors", but it also answers a few fun questions like why are * and ∧ so similar? (They are similar functions that operate in different "categories".) Admittedly that's a very rough, lay gloss on it, but it's still an interesting perspective on what people talk about when they talk about Category Theory.
senderista•4h ago