Determining Age of Universe w/ Hubbles Constant

  • Thread starter Thread starter radius
  • Start date Start date
  • Tags Tags
    Age Universe
radius
Messages
10
Reaction score
0
Please can somebody explain how the age of the universe can be determined using Hubbles Constant?
If the constant is taken as 10km/s (just for the sake of easiness), how can this be figured out using calculations?

I appreciate any help!:smile:
 
Physics news on Phys.org
the current value of Hubble constant is 71km/s/Mpc,now if you want to calculate the Hubble time, that is the time that have passed since Big bang, you do:
T=1012/H
where H is the Hubble constant, the result gives the Hubble time in years. If I put 71 in H, if gives 14 billion of years
From the formula you can see that the Hubble constant diminish in value with time, as the Hubble time augments
 
Last edited:
From the center of universe when you look the outer most particle the velocity will be

v=H*X ---- X - Current radius of universe.

So the time of that particle to reach there(age of universe) is

X/V

Which is 1/H

That's it.. Age of universe is Inverse Of H..
This is the most silliest way of explaining it..
 
OK, so this has bugged me for a while about the equivalence principle and the black hole information paradox. If black holes "evaporate" via Hawking radiation, then they cannot exist forever. So, from my external perspective, watching the person fall in, they slow down, freeze, and redshift to "nothing," but never cross the event horizon. Does the equivalence principle say my perspective is valid? If it does, is it possible that that person really never crossed the event horizon? The...
In this video I can see a person walking around lines of curvature on a sphere with an arrow strapped to his waist. His task is to keep the arrow pointed in the same direction How does he do this ? Does he use a reference point like the stars? (that only move very slowly) If that is how he keeps the arrow pointing in the same direction, is that equivalent to saying that he orients the arrow wrt the 3d space that the sphere is embedded in? So ,although one refers to intrinsic curvature...
So, to calculate a proper time of a worldline in SR using an inertial frame is quite easy. But I struggled a bit using a "rotating frame metric" and now I'm not sure whether I'll do it right. Couls someone point me in the right direction? "What have you tried?" Well, trying to help truly absolute layppl with some variation of a "Circular Twin Paradox" not using an inertial frame of reference for whatevere reason. I thought it would be a bit of a challenge so I made a derivation or...
Back
Top