Raju Krishnamoorthy
Goal
The goal of this seminar is to study the recent work of Landesman-Litt, in particular on local systems of geometric origin over general curves. The main results are contained in
LL22b and
LL22c . We will focus on the case of unipotent monodromy at the cusps to avoid the machinery of (co)parabolic structures: the simplified version of the first paper may be found here:
LL22a . A program may be found
here .
Schedule
November 9
Raju
Introduction to local systems of geometric origin
Notes
November 14
Raju
Finish introduction
Notes
November 30
Josh
Atiyah bundles and isomonodromic deformations
Notes
December 7
Scott
the non-GGG lemma
December 14
Yichen
Prove Theorem 1.3.4 of [LL22a]. State Theorem 1.2.4 of [LL22a]
Notes
January 4 January 9
Bruno
Background of CPVHS and positivity. Prove Theorems 1.2.8, 1.2.4, and 1.2.6 of [LL22a].
Notes
January 11
Raju
Introduction to MCG. MCG-finite representations. State the main theorem of [LL22c]
Notes
January 18, 25
Vasily
Cohomology rank bound for a unitary local system on a versal family of curves
Notes
February 8 (15?)
TBA
Cohomological rigidity for canonical representations, the main theorem for unitary local systems.
February 15 (22?)
TBA
The main theorem for semi-simple local systems and arithmetic applications.
TBA
TBA
Applications to the Putnam-Wieland conjecture.
References
[LL22a], Landesman, A.; Litt, D. Isomonodromy, stability, and Hodge theory. Available here .
[LL22b], Landesman, A.; Litt, D. Geometric local systems on very general curves. arxiv:2202.00039 .
[LL22c], Landesman, A.; Litt, D. Canonical representations of surface groups. arxiv:2205.15352