I. Starting Out 0. Sales pitches....................................................37 1. Groups...........................................................43 2. Metric spaces....................................................55 II. Basic Abstract Algebra 3. Homomorphisms and quotient groups................................69 4. Rings and ideals.................................................81 5. Flavors of rings.................................................93 III. Basic Topology 6. Properties of metric spaces.....................................107 7. Topological spaces..............................................113 8. Compactness.....................................................123 IV. Linear Algebra 9. Vector spaces...................................................137 10. Eigen-things...................................................155 11. Dual space and trace...........................................165 12. Determinant....................................................173 13. Inner product spaces...........................................181 14. Bonus: Fourier analysis........................................189 15. Duals, adjoint, and transposes.................................199 V. More on Groups 16. Group actions overkill AIME problems...........................209 17. Find all groups................................................215 18. The PID structure theorem......................................221 VI. Representation Theory 19. Representations of algebras....................................233 20. Semisimple algebras............................................245 21. Characters.....................................................253 22. Some applications..............................................261 VII. Quantum Algorithms 23. Quantum states and measurements................................267 24. Quantum circuits...............................................275 25. Shor's algorithm...............................................283 VIII. Calculus 101 26. Limits and series..............................................291 27. Bonus: A hint of p-adic numbers................................303 28. Differentiation................................................315 29. Power series and Taylor series.................................327 30. Riemann integrals..............................................335 IX. Complex Analysis 31. Holomorphic functions..........................................345 32. Meromorphic functions..........................................361 33. Holomorphic square roots and logarithms........................371 34. Bonus: Topological Abel-Ruffini Theorem........................377 X. Measure Theory 35. Measure spaces.................................................383 36. Constructing the Borel and Lebesgue measure....................391 37. Lebesgue integration...........................................401 38. Swapping order with Lebesgue integrals.........................407 39. Bonus: A hint of Pontryagin duality............................415 XI. Probability (TO DO) 40. Random variables (TO DO).......................................423 41. Large number laws (TO DO)......................................425 42. Stopped martingales (TO DO)....................................433 XII. Differential Geometry 43. Multivariable calculus done correctly..........................449 44. Differential forms.............................................457 45. Integrating differential forms.................................469 46. A bit of manifolds.............................................481 XIII. Riemann Surfaces 47. Basic definitions of Riemann surfaces..........................493 48. Morphisms between Riemann surfaces.............................501 49. Affine and projective plane curves.............................507 50. Differential forms.............................................517 51. The Riemann-Roch theorem.......................................521 52. Line bundles...................................................527 XIV. Algebraic NT I: Rings of Integers 53. Algebraic integers.............................................537 54. The ring of integers...........................................543 55. Unique factorization (finally!)................................551 56. Minkowski bound and class groups...............................563 57. More properties of the discriminant............................583 58. Bonus: Let's solve Pell's equation!............................585 XV. Algebraic NT II: Galois and Ramification Theory 59. Things Galois..................................................593 60. Finite fields..................................................605 61. Ramification theory............................................611 62. The Frobenius element..........................................621 63. Bonus: A Bit on Artin Reciprocity..............................633 XVI. Algebraic Topology I: Homotopy 64. Some topological constructions.................................649 65. Fundamental groups.............................................661 66. Covering projections...........................................673 XVII. Category Theory 67. Objects and morphisms..........................................685 68. Functors and natural transformations...........................697 69. Limits in categories (TO DO)...................................709 70. Abelian categories.............................................711 XVIII. Algebraic Topology II: Homology 71. Singular homology..............................................721 72. The long exact sequence........................................735 73. Excision and relative homology.................................747 74. Bonus: Cellular homology.......................................755 75. Singular cohomology............................................767 76. Application of cohomology......................................779 XIX. Algebraic Geometry I: Classical Varieties 77. Affine varieties...............................................799 78. Affine varieties as ringed spaces..............................809 79. Projective varieties...........................................819 80. Bonus: B\'ezout's theorem......................................827 81. Morphisms of varieties.........................................835 XX. Algebraic Geometry II: Affine Schemes 82. Sheaves and ringed spaces......................................847 83. Localization...................................................859 84. Affine schemes: the Zariski topology...........................869 85. Affine schemes: the sheaf......................................877 86. Interlude: eighteen examples of affine schemes.................887 87. Morphisms of locally ringed spaces.............................903 XXI. Set Theory I: ZFC, Ordinals, and Cardinals 88. Interlude: Cauchy's functional equation and Zorn's lemma.......917 89. Zermelo-Fraenkel with choice...................................925 90. Ordinals.......................................................933 91. Cardinals......................................................945 XXII. Set Theory II: Model Theory and Forcing 92. Inner model theory.............................................955 93. Forcing........................................................967 94. Breaking the continuum hypothesis..............................977 XXIII. Appendix