Lecture 6 (Thu, Mar 27, 2008)
Bolibruch Impossibility Theorem
Revealing an obstruction for realization of a matrix group as the monodromy of a Fuchsian system on 
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Degree (Chern class) of a complex bundle vs. that of a subbundle. The total trace of residues of a meromorphic connexion.
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Linear algebra: Monoblock operators and their invariant subspaces.
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Local theory revisited: local invariant subbundles of a (resonant) Fuchsian singularity in the Poincaré–Dulac–Levelt normal form.
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Bolibruch connexions on the trivial bundle: theorem on the spectra of residues.
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Three Matrices
: the Bolibruch Counterexample.
Reading: Section 18E from the book (printing disabled).
Refresh your memory: Sections 16C-16D (local theory), 17E-17I (degree of bundles)
