Gamma (ebook)

Argumento de Gamma (ebook)

"[Gamma] is not a book about mathematics, but a book of mathematics. . . . [It] is something like a picaresque novel; the hero, Euler's constant g, serves as the unifying motif through a wide range of mathematical adventures."--Dan Segal, Notices of the American Mathematical Society

"This book is accessible to a wide range of readers, and should particularly appeal to those who feel a love for mathematics and are dissuaded by the dryness and formality of text-books, but are also not satisfied by the less rigorous approach of most popular books. Mathematics is presented throughout as something connected to reality. . . . Many readers will find in this book exactly what they have been missing."--Mohammad Akbar, Plus Magazine, Millennium Mathematics Project, University of Cambridge

"I like this book very much. So much, in fact, that I found myself muttering 'neat stuff!' all the way through. While it is about an important topic, there isn't a single competitor. This amazing oversight by past authors is presumably the result of the topic requiring an author with a pretty sophisticated mathematical personality. Havil clearly has that. His skillful weaving of mathematics and history makes the book a 'fun' read. Many instructors will surely find the book attractive."--Paul J. Nahin, author of Duelling Idiots and Other Probability Puzzlers and An Imaginary Tale

"This is an excellent book, mathematically as well as historically. It represents a significant contribution to the literature on mathematics and its history at the upper undergraduate and graduate levels. Julian Havil injects genuine excitement into the topic."--Eli Maor, author of e: The Story of a Number

"The book is enjoyable for many reasons. Here are just two. First, the explanations are not only complete, but they have the right amount of generality. . . . Second, the pleasure Havil has in contemplating this material is infectious."--Jeremy Gray, MAA Online

"This book is written in an informal, engaging, and often amusing style. The author takes pains to make the mathematics clear. He writes about the mathematical geniuses of the past with reverence and awe. It is especially nice that the mathematical topics are discussed within a historical context."--Ward R. Stewart, Mathematics Teacher

"It is only fitting that someone should write a book about gamma, or Euler's constant. Havil takes on this task and does an excellent job."--Choice

"This book is a joy from start to finish."--Gerry Leversha, Mathematical Gazette

"[A] wonderful book. . . . Havil's emphasis on historical context and his conversational style make this a pleasure to read. . . . Gamma is a gold mine of irresistible mathematical nuggets. Anyone with a serious interest in maths will find it richly rewarding."--Ben Longstaff, New Scientist0Foreword xv
Acknowledgements xvii
Introduction xix
Chapter One
The Logarithmic Cradle 1
1.1 A Mathematical Nightmare- and an Awakening 1
1.2 The Baron's Wonderful Canon 4
1.3 A Touch of Kepler 11
1.4 A Touch of Euler 13
1.5 Napier's Other Ideas 16
Chapter Two
The Harmonic Series 21
2.1 The Principle 21
2.2 Generating Function for Hn 21
2.3 Three Surprising Results 22
Chapter Three
Sub-Harmonic Series 27
3.1 A Gentle Start 27
3.2 Harmonic Series of Primes 28
3.3 The Kempner Series 31
3.4 Madelung's Constants 33
Chapter Four
Zeta Functions 37
4.1 Where n Is a Positive Integer 37
4.2 Where x Is a Real Number 42
4.3 Two Results to End With 44
Chapter Five
Gamma's Birthplace 47
5.1 Advent 47
5.2 Birth 49
Chapter Six
The Gamma Function 53
6.1 Exotic Definitions 53
6.2 Yet Reasonable Definitions 56
6.3 Gamma Meets Gamma 57
6.4 Complement and Beauty 58
Chapter Seven
Euler's Wonderful Identity 61
7.1 The All-Important Formula 61
7.2 And a Hint of Its Usefulness 62
Chapter Eight
A Promise Fulfilled 65
Chapter Nine
What Is Gamma Exactly? 69
9.1 Gamma Exists 69
9.2 Gamma Is What Number? 73
9.3 A Surprisingly Good Improvement 75
9.4 The Germ of a Great Idea 78
Chapter Ten
Gamma as a Decimal 81
10.1 Bernoulli Numbers 81
10.2 Euler -Maclaurin Summation 85
10.3 Two Examples 86
10.4 The Implications for Gamma 88
Chapter Eleven
Gamma as a Fraction 91
11.1 A Mystery 91
11.2 A Challenge 91
11.3 An Answer 93
11.4 Three Results 95
11.5 Irrationals 95
11.6 Pell's Equation Solved 97
11.7 Filling the Gaps 98
11.8 The Harmonic Alternative 98
Chapter Twelve
Where Is Gamma? 101
12.1 The Alternating Harmonic Series Revisited 101
12.2 In Analysis 105
12.3 In Number Theory 112
12.4 In Conjecture 116
12.5 In Generalization 116
Chapter Thirteen
It's a Harmonic World 119
13.1 Ways of Means 119
13.2 Geometric Harmony 121
13.3 Musical Harmony 123
13.4 Setting Records 125
13.5 Testing to Destruction 126
13.6 Crossing the Desert 127
13.7 Shuffiing Cards 127
13.8 Quicksort 128
13.9 Collecting a Complete Set 130
13.10 A Putnam Prize Question 131
13.11 Maximum Possible Overhang 132
13.12 Worm on a Band 133
13.13 Optimal Choice 134
Chapter Fourteen
It's a Logarithmic World 139
14.1 A Measure of Uncertainty 139
14.2 Benford's Law 145
14.3 Continued-Fraction Behaviour 155
Chapter Fifteen
Problems with Primes 163
15.1 Some Hard Questions about Primes 163
15.2 A Modest Start 164
15.3 A Sort of Answer 167
15.4 Picture the Problem 169
15.5 The Sieve of Eratosthenes 171
15.6 Heuristics 172
15.7 A Letter 174
15.8 The Harmonic Approximation 179
15.9 Different-and Yet the Same 180
15.10 There are Really Two Questions, Not Three 182
15.11 Enter Chebychev with Some Good Ideas 183
15.12 Enter Riemann, Followed by Proof(s)186
Chapter Sixteen
The Riemann Initiative 189
16.1 Counting Primes the Riemann Way 189
16.2 A New Mathematical Tool 191
16.3 Analytic Continuation 191
16.4 Riemann's Extension of the Zeta Function 193
16.5 Zeta's Functional Equation 193
16.6 The Zeros of Zeta 193
16.7 The Evaluation of (x) and p(x)196
16.8 Misleading Evidence 197
16.9 The Von Mangoldt Explicit Formula-and How It Is Used to Prove the Prime Number Theorem 200
16.10 The Riemann Hypothesis 202
16.11 Why Is the Riemann Hypothesis Important? 204
16.12 Real Alternatives 206
16.13 A Back Route to Immortality-Partly Closed 207
16.14 Incentives, Old and New 210
16.15 Progress 213
Appendix A
The Greek Alphabet 217
Appendix B
Big Oh Notation 219
Appendix C
Taylor Expansions 221
C.1 Degree 1 221
C.2 Degree 2 221
C.3 Examples 223
C.4 Convergence 223
Appendix D
Complex Function Theory 225
D.1 Complex Differentiation 225
D.2 Weierstrass Function 230
D.3 Complex Logarithms 231
D.4 Complex Integration 232
D.5 A Useful Inequality 235
D.6 The Indefinite Integral 235
D.7 The Seminal Result 237
D.8 An Astonishing Consequence 238
D.9 Taylor Expansions-and an Important Consequence 239
D.10 Laurent Expansions-and Another Important Consequence 242
D.11 The Calculus of Residues 245
D.12 Analytic Continuation 247
Appendix E
Application to the Zeta Function 249
E.1 Zeta Analytically Continued 249
E.2 Zeta's Functional Relationship 253
References 255
Name Index 259
Subject Index 263