Nonabelian Hodge Theory

Classically, Hodge theory and related constructions provided extra structure to abelian topological invariants of the usual topological spaces associated to algebraic varieties over (C. I would like to explain how, in analogy with these abelian constructions, certain nonabelian topological invariants of complex algebraic varieties have extra structures. We will be concerned with two related invariants, the space R of framed 71-dimensional representations of %\(X,x), and M, its universal categorical quotient by the action of G£(n). These are related to the nonabelian cohomology H(X,G^(n)), which is the set of isomorphism classes of representations, and which has a structure of non-Hausdorff space. The moduli space M is the set of Jordan equivalence classes of representations, the universal Hausdorff space to which the cohomology space maps. The representation space R is the cohomology of X relative to a choice of base point x. We will interpret R and M as nonabelian analogues of the abelian cohomology H(X,(C).

[1]  C. Simpson Higgs bundles and local systems , 1992 .

[2]  K. Corlette Archimedean superrigidity and hyperbolic geometry , 1992 .

[3]  N. Nitsure Moduli space of semistable pairs on a curve , 1991 .

[4]  A. Fujiki Hyperkähler structure on the moduli space of flat bundles , 1991 .

[5]  Carlos Simpson,et al.  Harmonic bundles on noncompact curves , 1990 .

[6]  C. Simpson Transcendental aspects of the Riemann-Hilbert correspondence , 1990 .

[7]  D. Toledo,et al.  Harmonic mappings of Kähler manifolds to locally symmetric spaces , 1989 .

[8]  C. Simpson Constructing variations of Hodge structure using Yang-Mills theory and applications to uniformization , 1988 .

[9]  Kevin Corlette,et al.  Flat $G$-bundles with canonical metrics , 1988 .

[10]  N. Hitchin THE SELF-DUALITY EQUATIONS ON A RIEMANN SURFACE , 1987 .

[11]  S. Donaldson Twisted harmonic maps and the self-duality equations , 1987 .

[12]  R. Hain The de Rham homotopy theory of complex algebraic varieties II , 1987 .

[13]  J. Morgan The algebraic topology of smooth algebraic varieties , 1986 .

[14]  Karen K. Uhlenbeck,et al.  On the existence of hermitian‐yang‐mills connections in stable vector bundles , 1986 .

[15]  S. Donaldson Anti Self‐Dual Yang‐Mills Connections Over Complex Algebraic Surfaces and Stable Vector Bundles , 1985 .

[16]  Y. Siu Complex-analyticity of harmonic maps and strong rigidity of compact Kähler manifolds. , 1979, Proceedings of the National Academy of Sciences of the United States of America.