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Astronomy

Primordial Non-Gaussianity and Galaxy Cluster Abundance

Quick fact

Even a small amount of primordial non-Gaussianity (characterized by a parameter fNL of order 1) can change the predicted number of extremely massive galaxy clusters by tens of percent, making cluster counts a very sensitive probe of early-universe physics.

Why this is interesting

The universe’s earliest moments might have left a faint, non-random fingerprint that helps determine where gigantic galaxy clusters form. How can such tiny deviations scale up to shape the cosmos?