Effects of a first-order phase transition on a hot astrophysical object

It is pointed out that if a first-order phase transition restoring the symmetry of the electroweak theory takes place in the core of an astrophysical object the core would expand due to the symmetric vacuum. The subsequent decay of the expanded symmetric vacuum would release a large amount of energy. It is conjectured that this efficient way of converting gravitational energy into heat and radiation may be at work in quasars and other active galactic nuclei. (orig.)