The $C_2$-equivariant ordinary cohomology of complex quadrics I: The antisymmetric case
Published: Oct 30, 2025
Last Updated: Oct 30, 2025
Authors:Steven R. Costenoble, Thomas Hudson
Abstract
In this, the first of three papers about $C_2$-equivariant complex quadrics, we calculate the equivariant ordinary cohomology of smooth antisymmetric quadrics. One of these quadrics coincides with a $C_2$-equivariant Grassmannian, and we use this calculation to prove an equivariant refinement of the result that there are 27 lines on a cubic surface in $\mathbb{P}^3$.