New answers tagged expansion
2
votes
Why is the Hubble time same with age of the universe assuming ideally constant expansion?
The present expansion of the universe follows Hubble's law
$$\frac{da}{dt} = H a\ , $$
where $H_0$ is the Hubble parameter and $a$ represents a scale factor (perhaps the distance between two galaxies)....
Top 50 recent answers are included
Related Tags
expansion × 227cosmology × 56
universe × 53
redshift × 36
dark-energy × 32
observable-universe × 24
hubble-constant × 24
galaxy × 21
space-time × 21
gravity × 18
big-bang-theory × 18
general-relativity × 14
space × 14
cosmological-inflation × 14
distances × 11
fate-of-universe × 11
astrophysics × 9
light × 9
galaxy-cluster × 9
cosmic-microwave-background × 9
observational-astronomy × 8
supernova × 5
gravitational-waves × 5
speed × 5
cosmological-horizon × 5