- #1
damasgate
- 10
- 0
CMB hot spots have a physical size that corresponds to the size of the horizon at age
300; 000 yrs. Assume one such hot spot region has been expanding together with the
universe, how big in physical size (express in unit of light-year) has it become today?
For this exercise, use a model of the universe that is matter-dominated and assume
Omega = 1, so a proportional to t^(2/3) For comparison, the Virgo super-cluster currently has a size of 100 million light years, and it is marginally expanding with the Hubble
ow. There
are no structure larger than a super-cluster in our universe today.
What I know and tried:
-I know that a matter dominated univese is 30% of the density of the univese.
-It look like "the physical size" is measured in (light years) somehow which also confuses me
I think I just need a jumpstart explanation to get this but I just don't know how to start
300; 000 yrs. Assume one such hot spot region has been expanding together with the
universe, how big in physical size (express in unit of light-year) has it become today?
For this exercise, use a model of the universe that is matter-dominated and assume
Omega = 1, so a proportional to t^(2/3) For comparison, the Virgo super-cluster currently has a size of 100 million light years, and it is marginally expanding with the Hubble
ow. There
are no structure larger than a super-cluster in our universe today.
What I know and tried:
-I know that a matter dominated univese is 30% of the density of the univese.
-It look like "the physical size" is measured in (light years) somehow which also confuses me
I think I just need a jumpstart explanation to get this but I just don't know how to start