Topologi på roterommet
BID, February 2013 (At h-bar)
1. Is size always important?
2. To comb the hair of a sphere
3. The Euler charcteristic
4. Fusion reactors
5. A flat world?
6. Pacman's universe
7. What is the shape of space?
8. A flat but finite universe
A. State spaces
B. The study of spaces
C. What is a deformation?
D. How to calculate with spaces
Our space is (3+1)D.
Most of us seem to assume space is infinite and fairly flat, and if you are somewhat myopic (like our 2D friends) this is how it seems.
General relativity: space's not flat.
However, anomalities in the background radiation makes the Poincaré sphere a candidate
(the absolutely coolest 3D-space
has a 120-fold symmetry!!
Build one for yourself by taking a dodecahedron and identify opposite faces.)