A note on the primitive cohomology lattice of a projective surface

The isometry class of the intersection form of a compact complex surface can be easily determined from complex-analytic invariants. For projective surfaces the primitive lattice is another naturally occurring lattice. The goal of this note is to show that it can be determined from the intersection lattice and the self-intersection of a primitive ample class, at least when the primitive lattice is indefinite. Examples include the Godeaux surfaces, the Kunev surface and a specific Horikawa surface. There are also some results concerning (negative) definite primitive lattices, especially for canonically polarized surfaces of general type.

Keywords

complex projective surfaces, primitive intersection lattice

2010 Mathematics Subject Classification

Primary 14J80, 32J15. Secondary 57N65.

Full Text (PDF format)

Received 30 December 2021

Received revised 17 January 2022

Accepted 21 January 2022

Published 30 January 2024