What foundational metric quantifies the clustering of the universe by measuring the probability of finding two galaxies separated by distance $r$?

Answer

Two-Point Correlation Function

The Two-Point Correlation Function, denoted as $\xi(r)$, measures the probability of finding two galaxies separated by distance $r$ relative to the probability if the universe were perfectly random, thereby quantifying clustering.

What foundational metric quantifies the clustering of the universe by measuring the probability of finding two galaxies separated by distance $r$?

#Videos

Understanding Large-Scale Structures in the Universe - YouTube

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