This is the second video in this lecture on simple groups, Lie groups and manifestations of symmetry.During the 19th century, the role of groups shifted from its origin in number theory and the theory of equations to its role in describing symmetry in geometry. In this video we talk about the history of the search for simple groups, the role of symmetry in tesselations, both Euclidean, spherical and hyperbolic, and the introduction of continuous groups, or Lie groups, by Sophus Lie. Along the way we meet briefly many remarkable mathematical objects, such as the Golay code whose symmetries explain partially the Mathieu groups, the exceptional Lie groups discovered by Killing, and some of the other sporadic simple groups, culminating with the Monster group of Fisher and Greiss. The classification of finite simple groups is a high point of 20th century mathematics and the cumulative efforts of many mathematicians.

1. History of Pythagoras' theorem
2. History of Pythagoras' Theorem II
3. History of Greek Geometry I
4. History of Greek Geometry II
5. History of Greek Number Theory
6. History of Greek Number Theory II
7. Infinity in Greek Mathematics
8. History of Number Theory and Algebra in Asia
9. History of Number Theory and Algebra in Asia II
10. History of Polynomial Equations
11. History of Polynomial Equations II
12. History of Analytic Geometry and the Continuum
13. History of Analytic Geometry and the Continuum II
14. History of Projective Geometry
15. History of Calculus
16. History of Infinite series
17. Mechanics and the Solar System
18. History of Non-Euclidean Geometry
19. The Number Theory Revival
20. Mechanics and Curves
21. Complex Numbers and Algebra
22. History of Differential Geometry
23. History of Topology
24. Hypercomplex Numbers
25. History of Complex Numbers and Curves
26. History of Group Theory
27. History of Galois Theory I
28. History of Galois Theory II
29. History of Algebraic Number Theory and Rings I
30. History of Algebraic Number Theory and Rings II
31. Simple groups, Lie groups, and the Search for Symmetry I
32. Simple groups, Lie groups, and the Search for Symmetry II

In this course, Prof. N.J. Wildberger from UNSW provides a great overview of the history of the development of mathematics. The course roughly follows John Stillwell's book 'Mathematics and its History' (Springer, 3rd ed)Starting with the ancient Greeks, we discuss Arab, Chinese and Hindu developments, polynomial equations and algebra, analytic and projective geometry, calculus and infinite series, number theory, mechanics and curves, complex numbers and algebra, differential geometry, topology and hyperbolic geometry.  This course is meant for a broad audience, not necessarily mathematics majors. All backgrounds are welcome to take the course and enjoy learning about the origins of mathematical ideas. Generally the emphasis will be on mathematical ideas and results, but largely without proofs, with a main eye on the historical flow of ideas. At UNSW, this is MATH3560 and GENS2005. NJ Wildberger is also the developer of Rational Trigonometry: a new and better way of learning and using trigonometry.