4.3.1 Law of Transformation of Christoffel Symbols of 1st Kind 110
4.3.2 Law of Transformation of Christoffel Symbols of 2nd Kind 111
4.4 Covariant Differentiation of Tensor 113
4.4.1 Covariant Derivative of Covariant Tensor 114
4.4.2 Covariant Derivative of Contravariant Tensor 115
4.4.3 Covariant Derivative of Tensors of Type (0,2) 116
4.4.4 Covariant Derivative of Tensors of Type (2,0) 118
4.4.5 Covariant Derivative of Mixed Tensor of Type (s, r) 120
4.4.6 Covariant Derivatives of Fundamental Tensors and the Kronecker Delta 120
4.4.7 Formulas for Covariant Differentiation 122
4.4.8 Covariant Differentiation of Relative Tensors 123
4.5 Gradient, Divergence, and Curl 129
4.5.1 Gradient 130
4.5.2 Divergence 130
4.5.2.1 Divergence of a Mixed Tensor (1,1) 132
4.5.3 Laplacian of an Invariant 136
4.5.4 Curl of a Covariant Vector 137
4.6 Exercises 141
5 Riemannian Geometry 143
5.1 Introduction 143
5.2 Riemannian-Christoffel Tensor 143
5.3 Properties of Riemann-Christoffel Tensors 150
5.3.1 Space of Constant Curvature 158
5.4 Ricci Tensor, Bianchi Identities, Einstein Tensors 159
5.4.1 Ricci Tensor 159
5.4.2 Bianchi Identity 160
5.4.3 Einstein Tensor 166
5.5 Einstein Space 170
5.6 Riemannian and Euclidean Spaces 171
5.6.1 Riemannian Spaces 171
5.6.2 Euclidean Spaces 174
5.7 Exercises 175
6 The e-Systems and the Generalized Kronecker Deltas 177
6.1 Introduction 177
6.2 e-Systems 177
6.3 Generalized Kronecker Delta 181
6.4 Contraction of δijk αβγ 183
6.5 Application of e-Systems to Determinants and Tensor Characters of Generalized Kronecker Deltas 185
6.5.1 Curl of Covariant Vector 189
6.5.2 Vector Product of Two Covariant Vectors 190
6.6 Exercises 192
Part II: Differential Geometry 193
7 Curvilinear Coordinates in Space 195
7.1 Introduction 195
7.2 Length of Arc 195
7.3 Curvilinear Coordinates in E 3 200
7.3.1 Coordinate Surfaces 201
7.3.2 Coordinate Curves 202
7.3.3 Line Element 205
7.3.4 Length of a Vector 206
7.3.5 Angle Between Two Vectors 207
7.4 Reciprocal Base Systems 210
7.5 Partial Derivative 216
7.6 Exercises 219
8 Curves in Space 221
8.1 Introduction 221
8.2 Intrinsic Differentiation 221
8.3 Parallel Vector Fields 226
8.4 Geometry of Space Curves 228
8.4.1 Plane 231
8.5 Serret-Frenet Formula 233
8.5.1 Bertrand Curves 235
8.6 Equations of a Straight Line 252
8.7 Helix 254
8.7.1 Cylindrical Helix 256
8.7.2 Circular Helix 258
8.8 Exercises 262
9 Intrinsic Geometry of Surfaces 265
9.1 Introduction 265
9.2 Curvilinear Coordinates on a Surface 265
9.3 Intrinsic Geometry: First Fundamental Quadratic Form 267
9.3.1 Contravariant Metric Tensor 270
9.4 Angle Between Two Intersecting Curves on a Surface 272
9.4.1 Pictorial Interpretation 274
9.5 Geodesic in R n 277
9.6 Geodesic Coordinates 289
9.7 Parallel Vectors on a Surface 291
9.8 Isometric Surface 292
9.8.1 Developable 293
9.9 The Riemannian–Christoffel Tensor and Gaussian Curvature 294
9.9.1 Einstein Curvature 296
9.10 The Geodesic Curvature 308
9.11 Exercises 319
10 Surfaces in Space 321
10.1 Introduction 321
10.2 The Tangent Vector 321
10.3 The Normal Line to the Surface 324
10.4 Tensor Derivatives 329
10.5 Second Fundamental Form of a Surface 332
10.5.1 Equivalence of Definition of Tensor b αβ 333
10.6 The Integrability Condition 334
10.7 Formulas of Weingarten 337
10.7.1 Third Fundamental Form 338
10.8 Equations of Gauss and Codazzi 339
10.9 Mean and Total Curvatures of a Surface 341
10.10 Exercises 347
11 Curves on a Surface 349
11.1 Introduction 349
11.2 Curve on a Surface: Theorem of Meusnier 350
11.2.1 Theorem of Meusnier 353
11.3 The Principal Curvatures of a Surface 358
11.3.1 Umbillic Point 360
11.3.2 Lines of Curvature 361
11.3.3 Asymptotic Lines 362
11.4 Rodrigue’s Formula 376
11.5 Exercises 379
12 Curvature of Surface 381
12.1 Introduction 381
12.2 Surface of Positive and Negative Curvatures 381
12.3 Parallel Surfaces 383
12.3.1 Computation of aαβ and b αβ 383
12.4 The Gauss-Bonnet Theorem 387
12.5 The n-Dimensional Manifolds 391
12.6 Hypersurfaces 394
12.7 Exercises 395
Part III: Analytical Mechanics 397
13 Classical Mechanics 399
13.1 Introduction 399
13.2 Newtonian Laws of Motion 399
13.3 Equations of Motion of Particles 401
13.4 Conservative Force Field 403
13.5 Lagrangean Equations of Motion 405
13.6 Applications of Lagrangean Equations 411
13.7 Himilton’s Principle 423
13.8 Principle of Least Action 427
13.9 Generalized Coordinates 430
13.10 Lagrangean Equations in Generalized Coordinates 432
13.11 Divergence Theorem, Green’s Theorem, Laplacian Operator, and Stoke’s Theorem in Tensor Notation 438
13.12 Hamilton’s Canonical Equations 442
13.12.1 Generalized Momenta 443
13.13 Exercises 444
14 Newtonian Law of Gravitations 447
14.1 Introduction 447
14.2 Newtonian Laws of Gravitation 447
14.3 Theorem of Gauss 451
14.4 Poisson’s Equation 453
14.5 Solution of Poisson’s Equation 454
14.6 The Problem of Two Bodies 456
14.7 The Problem of Three Bodies 462
14.8 Exercises 467
Appendix A: Answers to Even-Numbered Exercises 469
References 473
Index 475
This is the only volume of its kind to explain, in precise and easy-to-understand language, the fundamentals of tensors and their applications in differential geometry and analytical mechanics with examples for practical applications and questions for use in a course setting.
Introduction to Differential Geometry with Tensor Applications discusses the theory of tensors, curves and surfaces and their applications in Newtonian mechanics. Since tensor analysis deals with entities and properties that are independent of the choice of reference frames, it forms an ideal tool for the study of differential geometry and also of classical and celestial mechanics. This book provides a profound introduction to the basic theory of differential geometry: curves and surfaces and analytical mechanics with tensor applications. The author has tried to keep the treatment of the advanced material as lucid and comprehensive as possible, mainly by including utmost detailed calculations, numerous illustrative examples, and a wealth of complementing exercises with complete solutions making the book easily accessible even to beginners in the field.
Groundbreaking and thought-provoking, this volume is an outstanding primer for modern differential geometry and is a basic source for a profound introductory course or as a valuable reference. It can even be used for self-study, by students or by practicing engineers interested in the subject.
Whether for the student or the veteran engineer or scientist, Introduction to Differential Geometry with Tensor Applications is a must-have for any library.
About the Author
Dipankar De, PhD, received his BSc and MSc in mathematics from the University of Calcutta, India and his PhD in mathematics from Tripura University, India. He has over 40 years of teaching experience and is an associate professor and guest lecturer in India. He has published many research papers in various reputed journal in the field of fuzzy mathematics and differential geometry.