How many parsecs is it when the redshift z=1

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The discussion focuses on converting redshift (z) to parsecs, emphasizing that the conversion depends on the chosen concept of distance. A simple equation for this conversion is not provided, but users reference tools like the lightcone calculator for calculations. One participant shares detailed results based on specific cosmological parameters, including values for R0, R∞, and other metrics. The importance of understanding the underlying cosmological model is highlighted, as it affects the conversion outcome. Overall, the thread provides insights into the complexities of redshift calculations and available resources for accurate conversions.
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How to convert red shift to parsecs? Is there a simple converting equation?
 
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nenyan said:
How to convert red shift to parsecs?

This depends on which concept of distance is used. See the first paragraph of the attached file.

nenyan said:
s there a simple converting equation?

I wrote up an answer for someone else, who specified z = 0.4. I didn't use dimensionless parameters. See the last two graphs in the attached file.
 

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very useful. thanks
 
George Jones said:
This depends on which concept of distance is used. See the first paragraph of the attached file.



I wrote up an answer for someone else, who specified z = 0.4. I didn't use dimensionless parameters. See the last two graphs in the attached file.

thats one of the better quality articles I've read. Far better than some of my attempts lol. Thank you for showing it.
 
My signature first link has a handy tool called the lightcone calculator here I set stretch to 2.0 for S_upper. S=1+z. I set a randon value for lower stretch.
then I selected the columns I wanted and decimal places. Clicked linear steps.
here is the result with WMAP
flat geometry parameters.

{\small\begin{array}{|c|c|c|c|c|c|}\hline R_{0} (Gly) & R_{\infty} (Gly) & S_{eq} & H_{0} & \Omega_\Lambda & \Omega_m\\ \hline 14.4&17.3&3400&67.9&0.693&0.307\\ \hline \end{array}} {\small\begin{array}{|r|r|r|r|r|r|r|r|r|r|r|r|r|r|r|r|} \hline a=1/S&S&z&T (Gy)&D_{now} (Gly)&D_{then}(Gly) \\ \hline 0.500&2.000&1.000&5.8636&11.046&5.523\\ \hline 1.000&1.000&0.000&13.7872&0.000&0.000\\ \hline 1.668&0.599&-0.401&21.7987&6.249&10.425\\ \hline 2.783&0.359&-0.641&30.4437&10.300&28.660\\ \hline 4.642&0.215&-0.785&39.2497&12.776&59.303\\ \hline 7.743&0.129&-0.871&48.0918&14.267&110.467\\ \hline 12.915&0.077&-0.923&56.9418&15.162&195.824\\ \hline 21.544&0.046&-0.954&65.7934&15.698&338.212\\ \hline 35.938&0.028&-0.972&74.6452&16.020&575.729\\ \hline 59.948&0.017&-0.983&83.4973&16.213&971.932\\ \hline 100.000&0.010&-0.990&92.3494&16.328&1632.838\\ \hline \end{array}}

the top row has the result you want you just need to convert to parsecs.
 
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