Thanks OnlyMe, you posted the lion's share of my post.
H=71.3 km/s/Mpc.
This means that for every 1Mpc distance the recession velocity increases by 71.3 km/s. In the second example you used a distance of 2Mpc so the answer would be:
H=142 km/s/2Mpc.
This means that for every 2Mpc distance the recession velocity increases by 142 km/s. This goes for a distance of 1Gly too, the answer would be H=21,882 km/s/Gly and the same reason applies. So yes, 2X the HC.
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Mpc is the traditional unit used and so there was no reason to change it as the standard. Nothing says that H has to be in units of Mpc.
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If you're so inclined you could rearange this equation to find the age of the universe.
(r*c)/H=a
The most accurate measurement of H has it at 73.8 +/- 2.4 km/s/Mpc. That would put the actual age of the universe somewhere between 13.7Gyr, 13.2Gyr and 12.8Gyr old.
http://blogs.discovermagazine.com/b...panding-at-73-8-2-4-kmsecmegaparsec-so-there/
I warn you, this article is total pop-sci. It's like reading a transcrip of Science Friday's on NPR.
This is where you are wrong. In the first example we used a distance for 1Mpc so the answer would be:Originally Posted by [/b]origin[/b]
For r=2
H = 142 km/s/Mpc (oops it is going bad this 2X the HC)
And so on so this equation has only one distance that will yield a number that is close to the hubble constant for all other distances it is wrong. Which means this equation does not work.
H=71.3 km/s/Mpc.
This means that for every 1Mpc distance the recession velocity increases by 71.3 km/s. In the second example you used a distance of 2Mpc so the answer would be:
H=142 km/s/2Mpc.
This means that for every 2Mpc distance the recession velocity increases by 142 km/s. This goes for a distance of 1Gly too, the answer would be H=21,882 km/s/Gly and the same reason applies. So yes, 2X the HC.
.
Mpc is the traditional unit used and so there was no reason to change it as the standard. Nothing says that H has to be in units of Mpc.
.
If you're so inclined you could rearange this equation to find the age of the universe.
(r*c)/H=a
The most accurate measurement of H has it at 73.8 +/- 2.4 km/s/Mpc. That would put the actual age of the universe somewhere between 13.7Gyr, 13.2Gyr and 12.8Gyr old.
http://blogs.discovermagazine.com/b...panding-at-73-8-2-4-kmsecmegaparsec-so-there/
I warn you, this article is total pop-sci. It's like reading a transcrip of Science Friday's on NPR.
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