Chiral Hodge Cohomology and Mathieu Moonshine.

We construct a filtration of chiral Hodge cohomolgy of a K3 surface |$X$|⁠ , such that its associated graded object is a unitary representation of the |$\mathcal{N}=4$| superconformal vertex algebra with central charge |$c=6$| and its subspace of primitive vectors has the property; its equivariant character for a symplectic automorphism |$g$| of finite order acting on |$X$| agrees with the McKay–Thompson series for |$g$| in Mathieu moonshine. [ABSTRACT FROM AUTHOR]