Contents Chapter 1 Hausdorff Measure 1 1.1 Preliminaries,Definitions and Properties 2 1.2 Isodiametric Inequality and H 9 1.3 Densities 13 1.4 Some Further Exlensions Related to Hausdorlf Measures 23 Chapter 2 Fine Properties of Functioeaead Sets and Their AppIications 33 2.1 Lebesgue Poinls of Sobolev Functions 33 2.2 Self-Similar Sets 45 2.3 Federer's Reduction Principle 49 Chapter 3 Lipschitz Functioeaead Rectifiable Sets 60 3.1 Lipschitz Functions 61 3.2 5ubmanifold of R 67 3.3 Countably n-Rectifiable Sets 70 3.4 Weak Tangent Space Property,Measures in Cones and Rectifiability 77 3.5 Density and Rectifiability 89 3.6 Ortbogonal Projections and Rectifiability 97 Chapter 4 The Area and Co-area Foreau1ae 105 4.1 Area Formula and It Proof 105 4.2 Co-area Forrnula 111 4.3 50ne Exlensions and Remarks 116 4.4 The First and Second Variation Formulae 123 Chapter 5 BV Functions and Sets of FirtitePerimeter 127 5.1 Introduclion and Defmitions 127 5.2 Properties 129 5.3 Soholev and Isoperimetric Inequalities 134 5.4 The Co-area Formula for BV Functions 139 5.5 The Reduced Boundary 142 5.6 Further Properties and Results Relative to BV Functions 149 Chapter 6 Theory of Varifolds 154 6.1 Measures of Oscillation 154 6.2 Basic Definitions and the First Variation 161 6.3 Monotonicity Formula and Isoperimetric Inequality 165 6.4 Rectifiahility Theorem and Tangent Cones 168 6.5 The Regularity Theory 173 Chapter 7 Theory of Currents 179 7.1 Forms and Currents 179 7.2 Mapping Currents 185 7.3 Integral Rectifiahle Currents 189 7.4 Deformation Theorem 194 7.5 Rectifiahility of Currents 198 7.6 Compactness Theorem 204 Chapter 8 Mass Minimizing Currents 209 8.1 Properties of Area Minimizing Currents 209 8.2 Excess and Height Bound 212 8.3 Excess Decay Lemmas and Regularity Thleory 219 Bihliography 228 Index 235