Goethe University solution shows collapsing stars can birth gravastars via embedded mini-universes

Jampolski solved the Einstein field equations under spherical symmetry with a time-dependent interior metric that transitions from ordinary matter collapse to a de Sitter-like phase once density exceeds a critical threshold. The model treats the emerging mini-universe as a separate FLRW region whose expansion supplies the repulsive pressure that halts further infall, yielding a thin shell of ordinary matter surrounding a dark-energy core without an event horizon or central singularity.

The construction directly addresses the 25-year open question of gravastar formation from realistic initial data. Unlike static thin-shell models, the new spacetime evolves continuously from stellar collapse, showing that the required dark-energy phase can arise dynamically once compression reaches Planck-scale densities where new physics is expected.

A central limitation remains that the solution is purely classical and depends on an assumed equation of state at trans-Planckian densities that cannot be tested in laboratories. Confirmation would require either a full quantum-gravity embedding or an observable signature, such as gravitational-wave echoes from the reflective surface, detectable by future instruments at strain amplitudes below 10^-24.