The paper explores how resonance locking, the coupling of a planet's orbit to a stellar gravity mode (g-mode), can explain the correlation between stellar obliquity and effective temperature in hot Jupiter systems. Cool stars with radiative cores are more likely to have increased g-mode frequencies due to core hydrogen burning, leading to stronger tidal evolution and damping of semi-major axes, eccentricities, and obliquities. In contrast, hotter stars without radiative cores preserve initial spin-orbit misalignments. The study focuses on axisymmetric g-modes but also discusses non-axisymmetric modes. The authors derive equations governing the evolution of the planet's orbit, stellar spin, and obliquity, and use stellar evolution models to show that g-mode frequencies evolve differently between cool and hot stars. They find that obliquities damp more readily for cool stars, aligning their spins with the stellar spin, while hot stars' obliquities remain largely unchanged. The paper also discusses the limitations of the theory, such as the uncertainty in the damping of tidally excited modes, and provides a population synthesis model that reproduces the observed correlation between stellar obliquity and effective temperature.The paper explores how resonance locking, the coupling of a planet's orbit to a stellar gravity mode (g-mode), can explain the correlation between stellar obliquity and effective temperature in hot Jupiter systems. Cool stars with radiative cores are more likely to have increased g-mode frequencies due to core hydrogen burning, leading to stronger tidal evolution and damping of semi-major axes, eccentricities, and obliquities. In contrast, hotter stars without radiative cores preserve initial spin-orbit misalignments. The study focuses on axisymmetric g-modes but also discusses non-axisymmetric modes. The authors derive equations governing the evolution of the planet's orbit, stellar spin, and obliquity, and use stellar evolution models to show that g-mode frequencies evolve differently between cool and hot stars. They find that obliquities damp more readily for cool stars, aligning their spins with the stellar spin, while hot stars' obliquities remain largely unchanged. The paper also discusses the limitations of the theory, such as the uncertainty in the damping of tidally excited modes, and provides a population synthesis model that reproduces the observed correlation between stellar obliquity and effective temperature.