4
votes
1answer
69 views

Equivalence of definition for polarized K3

In the literature there are two different definitions of polarized K3 surfaces. 1) A polarized K3 is the data $(X,\omega)$. Where $X$ is a K3 surface and $\omega$ is an ample class in ...
5
votes
1answer
815 views

Intersection form on quotient manifold

I have a simple algebraic topology question. Let $M$ and $N$ be 2-dimensional oriented manifolds (say $H^{2}(M,\mathbb{Z})\cong \mathbb{Z}\alpha_{M}$ and $H^{2}(M,\mathbb{Z})\cong ...