Cosmos = e-t x Oin
To understand the structuring of the Cosmos, we can search similar elements in the same one that to be known and to have familiarity with them, they can help us to understand the problem better..
Probably the most famous equation of them all, E=mc2 results from Einstein's theory of special relativity and expresses the fact that mass and energy are the same physical entity and can be changed into each other.
It's simplicity is its power, as it unites two fundamental physical qualities of mass and energy..
Distances in Cosmology Distances in Cosmology Simplify notation by adopting c=1, so that E=m
Friedmann's equation is then:
The index i refers to the type of particle fluid under consideration, e
g matter or radiationIf the Universe is flat (k=0): So that we have Ωm , Ωr and ΩΛ for matter, radiation and dark energy
The Friedmann equation becomes: In a flat Universe, ΩΛ,0 + Ωm,0=1
Introduce Case 3 , Λ=0 : This is now the Einstein-deSitter case which we have already encountered in the last lecture
flat, pressureless universe with a small, but non-zero, cosmo- logical constant initially evolves as if it were Einstein-deSitter