Volume 149, Issue 1 – January 1999

## Rigidity of infinite disk patterns

Pages 1-2 by Zheng-Xu He

## Hard ball systems are completely hyperbolic

Pages 35-96 by Nándor Simányi, Domokos Szász

## Blowup of small data solutions for a quasilinear wave equation in two space dimensions

Pages 97-127 by Serge Alinhac

## Quantum cohomology of flag manifolds $G/B$ and quantum Toda lattices

Pages 129-148 by Bumsig Kim

## Homogeneity of infinite dimensional isoparametric submanifolds

Pages 149-181 by Ernst Heintze, Xiaobo Liu

## The instability of naked singularities in the gravitational collapse of a scalar field

Pages 183-217 by Demetrios Christodoulou

## On finite homomorphic images of the multiplicative group of a division algebra

Pages 219-251 by Yoav Segev

## Basepoint freeness for nef and big line bundles in positive characteristic

Pages 253-286 by Seán Keel

## Continuous families of isospectral metrics on simply connected manifolds

Pages 287-308 by Dorothee Schueth

## A counterexample to the “hot spots” conjecture

Pages 309-317 by Krzysztof Burdy, Wendelin Werner