Implications of GW241011 for rotating exotic compact objects

TL;DR

This paper uses gravitational wave data from GW241011 to constrain the nature of its primary object, ruling out many exotic models but leaving some highly compact alternatives plausible.

Contribution

It provides the first gravitational wave constraints on the spin-induced quadrupole moment of GW241011, testing the viability of various exotic compact object models.

Findings

Many exotic models are ruled out by the data.

Highly compact objects with C ≥ 0.24 remain viable.

Constraints improve understanding of compact object nature.

Abstract

A number of theoretical proposals have been made for horizonless compact objects with masses and spins similar to those of black holes. While gravitational wave signatures from their mergers can resemble those of black holes, features like the spin-induced quadrupole moment may reveal their distinct nature. Using the tight bounds on the spin-induced quadrupole moment of GW241011, we place gravitational wave constraints on the nature of its primary. We find that large classes of exotic compact objects (including rotating boson stars) cannot explain its nature, however, models of sufficiently large compactness of $C \gtrsim 0.24$ may still be viable contenders.