Calculating Mass Density of the Universe with SDSS DR10 Quasar Catalog

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The SDSS DR10 quasar catalog has been released, compiling over 166,583 spectroscopically confirmed quasars, with a significant number at high redshifts. This catalog includes quasars from various selection programs and covers an extensive area of 6,373 square degrees. The excitement around the catalog stems from its potential to enhance our understanding of the universe's mass density over time. Previous attempts to analyze earlier data highlighted the challenges and complexities involved in such calculations. The release marks a significant milestone in quasar research and offers new opportunities for astrophysical studies.
Chronos
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The latest quasar catalog, SDSS DR10, has been released - http://arxiv.org/abs/1311.4870! Yes, I know, you can hardly contain your excitement.
 
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I've got excitement oozing out my eyeballs. It's pretty sweet.
 
Good god, my mind is already blown in the first paragraph.

The first two stages of the SDSS discovered and spectroscopically confirmed more than 105,000 quasars (Schneider et al. 2010), mainly at low redshift (z ≤ 2).

I had no idea there were over 100,000 known quasars...

Edit: Gah! Even more!

This paper presents the SDSS-DR10 quasar catalog, denoted
DR10Q, which compiles all the spectroscopically-confirmed
quasars identified during the first three years of BOSS operations
and released as part of the SDSS tenth data release (Ahn et al.
2013). This catalog contains quasars targeted by the main quasar
target selection (Ross et al. 2012), the BOSS ancillary programs
(Dawson et al. 2013) and serendipitous discoveries in the galaxy
targets. It contains 166,583 unique quasars, including 117,668
with z > 2.15, over an area of 6,373 deg2
 
This sounds a little weird, but, I pasted one of the earlier DR releases onto an excel spreadsheet circa 2006, whereupon I discovered the [then] ~65500 row limit. What can I say? I needed a hobby. I thought it would be fascinating to calculate the approximate mass density of the universe over time this way. It was a spectacular success, I ended up spectacularly confused.
 
Chronos said:
This sounds a little weird, but, I pasted one of the earlier DR releases onto an excel spreadsheet circa 2006, whereupon I discovered the [then] ~65500 row limit. What can I say? I needed a hobby. I thought it would be fascinating to calculate the approximate mass density of the universe over time this way. It was a spectacular success, I ended up spectacularly confused.

Buahaha!
 
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https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
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