GEPI

The fragile light element lithium is easily burned in stellar interiors, which makes it a sensitive diagnostic of internal stellar mixing.

I review the basic angular momentum evolution and mixing pictures for stars, and argue that rotation is correlated with lithium depletion and that differences in the initial rotation rates are driven by interactions between protostars and their accretion disks. This provides a possible causal linkage between the presence of planets and the degree of mixing in their host stars. Major open questions related to mixing and rotational evolution are highlighted and discussed.