Title: On SDP-based Approximation Algorithms for Minimizing a
       Nonconvex Quadratic Function Subject to Ellipsoid Constraints


			   Paul Tseng
			   Mathematics
			Univ. Washington
		     Seattle, WA 98195-4350
		   tseng@math.washington.edu


Abstract:
We describe recent developments on SDP-based approximation algorithms for 
minimizing a nonconvex quadratic function subject to ellipsoid constraints.
We survey bounds on the optimality gap, including recent improvements, and
present numerical experience with 2-ellipsoid trust region algorithms.