Thesis (Ph. D.)--Lehigh University, 2002. / Includes vita. Includes bibliographical references (leaves 70-74).

by Fan Xuqian. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 99-100). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.5 / Chapter 2 --- The Theorem of Efimov --- p.7 / Chapter 2.1 --- The Idea of the Proof of the Efimov's Theorem --- p.8 / Chapter 2.2 --- Proof of the Efimov's Main Lemma --- p.12 / Chapter 2.3 --- Proof of Lemma 2.3 --- p.48 / Chapter 2.4 --- Proof of Lemma 2.4 --- p.52 / Chapter 3 --- Isometric Immersion into R3 of Complete Surfaces with Negative Curvature --- p.62 / Chapter 3.1 --- The Sketch of the Proof of Theorem 3.1 --- p.66 / Chapter 3.2 --- Proof of Lemma 3.4 --- p.75 / Chapter 3.3 --- Proof of Lemma 3.5 --- p.76 / Chapter 3.4 --- Proof of Lemma 3.6 --- p.86 / Chapter 3.5 --- Proof of Lemma 3.7 --- p.89 / Chapter 3.6 --- The Geometric Properties of the Immersion --- p.95

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O objetivo dessa dissertaÃÃo à apresentar uma fÃrmula para o operador Lr(g) = div(Pr gradiente g) de uma nova funÃÃo suporte g, definida sobre uma hipersuperfÃcie M n em uma forma espacial Riemanniana Mc n+1, bem como mostrar que uma hipersuperfÃcie diferenciÃvel estrelada compacta Σn, com segunda funÃÃo simÃtrica S2 constante positiva na esfera Euclidiana S n+1, deve ser uma esfera geodÃsica Sn (p). Isso generaliza um resultado obtido por Jellett [9] em 1853 para tais tipos de superfÃcies no espaÃo Euclidiano R3. / The purpose of this dissertation is to desire a formula for the operator Lr(g) = div(Pr gradient g) of a new support function g, defined over a hypersurface Mn in a Riemannian space form Mc n +1, and to show that a compact smooth starshaped hypersurface Σn in the Euclidean sphere Sn+1,whose second symmetric function S2 is positive and constant must be a geodesic sphere Sn (p). This generalizes a result obtained by Jellett [9] in 1853 for such surfaces in Euclidean space R3.