4
Theoretical Framework
•Section 5.1, the “Cosmological Principle”
–Isotropic, homogenous, uniform expansion
–Can write relativistic equations in different forms (famous names cited here…)
–Weyl’s postulate:  “The particles of the substratum (representing the nebulae) lie in space-time on a bundle of geodesics diverging from a porint in the (finite or infinite) past.”