Heat Kernel on Noncomplete Manifolds Pei Hsu Indiana University Mathematics Journal 1990 text pdf 10.1512/iumj.1990.39.39023 10.1512/iumj.1990.39.39023 en Indiana Univ. Math. J. 39 (1990) 431 - 442 state-of-the-art mathematics http://iumj.org/access/