
#1
Oct710, 04:45 PM

P: 2,890

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

Sci Advisor
P: 8,004




#3
Oct810, 02:56 AM

P: 1,555





#4
Oct810, 03:01 AM

P: 2,890

velocity and redshift 



#5
Oct810, 11:01 AM

P: 2,890

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

Mentor
P: 6,038

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



#7
Oct810, 01:15 PM

P: 256

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



#8
Oct810, 01:43 PM

P: 2,890

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: 2,890

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

Mentor
P: 6,038





#11
Oct810, 02:56 PM

P: 256





#12
Oct810, 05:20 PM

P: 256

What debate? 


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