## Wild harmonic bundles and related topics II

Harmonic bundles are flat bundles equipped with a pluri-harmonic metric. They are very useful in the study of flat bundles on complex projective manifolds. Indeed, according to the fundamental theorem of Corlette, any semisimple flat bundle on a projective manifold has a pluri-harmonic metric. Moreover, Simpson generalized many important theorems for polarizable variation of Hodge structures, such as Hard Lefschetz Theorem, to the context of harmonic bundles.