- #1
tortin
- 2
- 0
Hi, I was looking through past exams for one of my courses, and I came across a question I wasn't quite sure how to do, so I was wondering if anyone could give some hints (or possibly the rationale for solution), thanks!
Observers in three universes A, B, and C measure identical constants. However, universe A is a critical universe (i.e. p = pc (with c being critical density), Universe B is an accelerating universe, and Universe C is close to being an empty universe (i.e. p<<pc or p~0). Rank the ages of the three universes as measured by these observers from largest to smallest, and explain your reasoning.
None really...
I'm not quite sure what you can infer about the age of A if it's a critical universe, because it always stays flat with p = pc. C is probably the oldest universe, since it's emptying out, and I'd guess B is younger than C, since it's accelerating so not yet emptied out.
However, I was also wondering what the relevance of the identical Hubble constants would give in this problem.Thanks for anyone who can give some help / hints!
edit - maybe this should be in advanced physics forum?
Homework Statement
Observers in three universes A, B, and C measure identical constants. However, universe A is a critical universe (i.e. p = pc (with c being critical density), Universe B is an accelerating universe, and Universe C is close to being an empty universe (i.e. p<<pc or p~0). Rank the ages of the three universes as measured by these observers from largest to smallest, and explain your reasoning.
Homework Equations
None really...
The Attempt at a Solution
I'm not quite sure what you can infer about the age of A if it's a critical universe, because it always stays flat with p = pc. C is probably the oldest universe, since it's emptying out, and I'd guess B is younger than C, since it's accelerating so not yet emptied out.
However, I was also wondering what the relevance of the identical Hubble constants would give in this problem.Thanks for anyone who can give some help / hints!
edit - maybe this should be in advanced physics forum?