5. Model Universes Flashcards
1
Q
What is the energy density proportional to for matter, radiation and cosmological constant dominated universe?
A
Matter: a^-3
Rad: a^-4
Cos: Constant
2
Q
When can one component of the universe be considered?
A
When one component dominates
3
Q
What is kappa equal to?
A
k*R_0^2 - R_0 is the radius of curvature Equal to -1 for open universe 0 for flat 1 for closed
4
Q
Why does a radiation dominated universe evolve more slowly than a matter dominated one?
A
Radiation pressure
5
Q
What is the radiation pressure in the benchmark model?
A
CMB and neutrinos
6
Q
What is the matter in the benchmark model?
A
Baryonic matter and non-baryonic dark matter
7
Q
What is the equation for the age of the universe
A
2/3(1+w) * 1/H(0)
8
Q
How does the scale factor evolve in the benchmark model for the universe?
A
Smoothly with time
- Transitions between component dominated universes
