Some massive stars are such overachievers they explode twice because their centers turn into a weird "quark soup."
arXiv · March 18, 2026 · 2603.15791
The Takeaway
In certain super-bright explosions, the core of the star reaches such extreme density that it collapses into deconfined quark matter. This 'phase transition' acts as a secondary engine, injecting a huge second wind of energy into the explosion weeks after it first began.
From the abstract
We show that delayed (weeks-months) energy injection into expanding Type Ic supernova (SN) ejecta can reproduce the luminosity and spectral evolution of hydrogen-poor superluminous SNe (SLSNe-I). Late-time reheating sets the radiation temperature and density needed for the W-shaped OII absorption near peak, explaining its disappearance as the ejecta cools without extra excitation mechanisms. In our model, the neutron star (NS) undergoes a core phase transition to deconfined quark matter at time