Speaker
Description
The $I$-Love-$Q$ relations refer to the existence of various approximate equation of state-independent relations involving the moment of inertia, Love number, and quadrupole moment. These relations have an interesting applicability in observational astrophysics since they allow the inference of two quantities within the $I$-Love-$Q$ trio out of a third one alone. However, the quantities involved in the $I$-Love-$Q$ relations are normalized by the parameter $M_0$, which arises in the usual perturbative analytical approach as the mass of the background configuration. However, since $M_0$ is not the mass of the rotating star $M_S$, it is not an observable quantity, and therefore the applicability of the relations to actual observations gets tainted. This problem is usually overcome by taking $M_0$ to be the mass of the star -- an approximation that can, in some scenarios, be too risky. In this talk, I will explain how to extract the value of $M_0$ using an extended version of the universal relations, which includes additional relations involving $\delta M \propto M_S-M_0$, and analyze the extent to which the use of these extended relations provides a more precise inference of the properties of the star, and its equation of state.
