(a) Using an order-of-magnitude analysis based on Eq. (27.60), show that the strongest gravitational waves that are likely to occur each year in LIGO’s HF band have h₊ ∼ h_× ∼ 10⁻²¹—which is the actual amplitude of LIGO’s first observed wave burst, GW150914.

(b) As a concrete example, estimate the gravitational-wave strength from the final moments of inspiral and merger of two black holes, as described by Eqs. (27.71) and (27.70b) extrapolated into the highly relativistic domain.

Equations.

h+~hx ns 'kin r Ens kin G- cAr (27.60)