Overview
- The study, published in mid‑June 2026, delivers a mathematical solution in general relativity showing how a tiny, dark‑energy‑filled bubble at a collapsing star’s center can expand and counteract infall.
- The expanding bubble acts like a mini‑universe whose outward pressure can halt collapse before a singularity or event horizon forms, producing an object externally similar to a black hole but internally different.
- A precise compactness threshold governs the outcome: the star’s initial mass-to-radius ratio must not exceed 3/8 (0.375) for a Gravastern to form, otherwise collapse proceeds to a black hole.
- Authors Daniel Jampolski and Luciano Rezzolla stress the result is theoretical and does not displace black holes as the simplest explanation; whether real stars meet the strict compactness condition remains unknown and must be tested.
- The work advances a 25‑year discussion of ultra‑compact alternatives by giving a concrete, testable mechanism inside classical relativity and points to future observational and theoretical work to distinguish horizonless objects from true black holes.