Geometry Seminar

 

Almost geodesic compact holomorphic curves on quotients of bounded symmetric domains

Professor Ngaiming MOK

The University of Hong Kong

 

Abstract

 

Let D be a bounded symmetric domain, X be a complex manifold uniformized by D, and S be a compact complex submanifold of X.  For e > 0 we will say that S is e-geodesic if the second fundamental form of S in X is bounded by e at every point.

 

I will show that, when D is the 2-disk, for every e > 0 there exists an e-geodesic compact holomorphic curve on some X uniformized by D. This implies the same statement for a bounded symmetric domain of rank ³ 2.  This results from a recent construction by Eyssidieux and myself of  examples of holomorphic maps f between compact Riemann surfaces of higher genus such that the sup norm image001 with respect to Poincaré metrics is smaller than any pre-assigned constant.

 

Given D, there are only a finite number of complex totally geodesic submanifolds D' up to holomorphic isometries of D, and one can raise a more refined question for each such pair (D, D'), asking whether e-geodesic compact holomorphic submanifolds S modelled on D' are necessarily totally geodesic.  The examples in the above show that for certain D' of dimension 1 this fails to be the case. I will explain why for certain pairs (D, D') with dim(D') = 1 the answer is in fact positive.  We say in this case that (D, D') exhibits gap rigidity.

 

Date:

October 7, 2004 (Thursday)

Time:

4:00 – 5:30pm

Place:

Room 517, Meng Wah Complex

 

 

All are welcome