Quantum Effects May Reshape Gravity in Extreme Cosmic Environments

Researchers at the University of Sussex are refining how quantum effects might alter gravity in extreme environments. Xavier Calmet and Marco Sebastianutti are leading the effort to model celestial bodies with greater accuracy. Their work aims to address long-standing inconsistencies in gravitational theory. Previous attempts to include quantum corrections often produced unrealistic results. Diverging quantities at the surfaces of compact objects signalled a breakdown in the theory. To fix this, the team adopted a modified Tolman VII density profile, ensuring smooth density changes up to the star’s surface.

The researchers focused on the spacetime metric at the boundary of celestial bodies. By adding higher-order curvature terms to general relativity, they explored how corrections affect mass, radius, and density distribution. Perturbative calculations of the exterior metric yielded stable outcomes, revealing a subtle 'quantum hair' feature at higher orders.

This approach provides a framework for incorporating quantum effects into gravitational equations. The team determined the conditions needed for regular, physically meaningful corrections, offering a clearer picture of extreme gravitational environments. The new method resolves past inconsistencies in modelling quantum corrections. It delivers well-behaved results and improves the description of compact objects. This advancement paves the way for more accurate theories of gravity in extreme conditions.