# Fortnightly links (30)

Daniel Huybrechts, Motives of derived equivalent K3 surfaces is a short but cute paper, showing that derived equivalent K3 surfaces have isomorphic Chow motives. Equality of invariants deduced from motives (e.g. the zeta function if the K3 surface is defined over a finite field) was already known, but now it has been shown in complete generality that all these equalities can be lifted to an isomorphism of the Chow motives for derived equivalent K3 surfaces. Cool!

The fight to fix symplectic geometry is an interesting article on the state of the foundations in symplectic geometry.

NIST Digital Library of Mathematical Functions is an online version of

*the*standard reference on special functions by Abramowitz and Stegun. I really enjoy the quality of the website, as a showcase of how it should be done. Soon I will explain on this blog what this picture (for different values of $\alpha$ and $\beta$) has to do with the Hochschild cohomology of $\mathbb{P}^n$ and Gerstenhaber algebras.