Proca Stars in Higher-Derivative Gravity: Frozen Stars Emerge
Analysis
Key Takeaways
- •Investigates Proca stars in a higher-derivative gravity framework.
- •Identifies 'frozen stars' as horizonless, singularity-free solutions.
- •Frozen stars mimic extremal black holes outside a critical radius.
- •The behavior depends on the coupling constant and the order of curvature corrections.
“Frozen stars contain neither curvature singularities nor event horizons. These frozen stars develop a critical horizon at a finite radius r_c, where -g_{tt} and 1/g_{rr} approach zero. The frozen star is indistinguishable from that of an extremal black hole outside r_c, and its compactness can reach the extremal black hole value.”