Catalog variance of testing general relativity with gravitational-wave data

Understand

Combining multiple gravitational-wave observations allows for stringent tests of general relativity, targeting effects that would otherwise be undetectable using single-event analyses.

• We highlight how the finite size of the observed catalog induces a significant source of variance.
• If not appropriately accounted for, general relativity can be excluded with arbitrarily large credibility even if it is the underlying theory of gravity.
• This effect is generic and holds for arbitrarily large catalogs.