Testing the first law of black hole mechanics with GW150914

TL;DR

This paper tests a weaker version of the first law of black hole mechanics using gravitational wave data from GW150914, finding results consistent with the law's validity at 68% confidence.

Contribution

It introduces a test for a relaxed version of the first law of black hole mechanics and applies it to GW150914 data to assess its validity.

Findings

The deviation parameter is constrained to 0.07 ± 0.11.

Results support the validity of the first law at 68% confidence.

The test provides a new way to verify black hole mechanics with gravitational waves.

Abstract

Whether the first law of black hole mechanics is correct is an important question in black holes physics. Subjected to current limited gravitational wave events, we propose its weaker version that permits a relatively large perturbation to a black hole system and implement a simple test with the first event GW150914. Confronting the strain data with the theory, we obtain the constraint on the deviation parameter $\alpha=0.07\pm0.11$, which indicates that this weaker version is valid at the 68\% confidence level. This result implies that the first law of black hole mechanics may be correct.