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Velocity and redshift 
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#1
Oct710, 04:45 PM

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What is the formula used to convert the measured redshift into a velocity?, not the approximated formula for low speeds v=cz , but the more general and accurate one.
Thanks. 


#2
Oct810, 02:50 AM

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#3
Oct810, 02:56 AM

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#4
Oct810, 03:01 AM

P: 3,043

Velocity and redshift



#5
Oct810, 11:01 AM

P: 3,043

v=[((1+z)^21)/((1+z)^2+1)]c=Ho*D c=light speed constant Ho=Hubble constant D=distance v=velocity 


#6
Oct810, 12:49 PM

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http://arxiv.org/abs/astroph/0310808. It is fairly easy to derive equation (1) from this paper. 


#7
Oct810, 01:15 PM

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[tex]v=H_{0}D[/tex] [tex]D=(c/H_{0})ln(1+z)[/tex] 


#8
Oct810, 01:43 PM

P: 3,043

The formula I used maybe is not correct for the Hubble law but I'm interested in the first part, express v as a function of z, is that so difficult? 


#9
Oct810, 02:04 PM

P: 3,043

Ok, I see what you mean, after looking at the paper and the formula again, I see what you mean, but according to some cosmologists the formula that doesn't give superluminal velocities is alright too, and anyway this is a cosmology debate that I find artificial and tiresome and I don't really wanna get into it , I think it's been discussed enough in these forums, just remember that people as prestigious as David Hogg supports the view of cosmological redshift as Doppler.



#10
Oct810, 02:05 PM

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#11
Oct810, 02:56 PM

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#12
Oct810, 05:20 PM

P: 256

What debate? 


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