Gamma-ray bursts as the birth-cries of black holes
  The origin of cosmic gamma-ray bursts remains one of the most intriguing puzzles in astronomy. We suggest that purely general relativistic effects in the collapse of massive stars could account for these bursts. The late formation of closed trapped surfaces can occur naturally, allowing the escape of huge energy from curvature-generated fireballs, before these are hidden within a black hole. 
Pankaj Joshi (Tata IFR), Naresh Dadhich (IUCAA), Roy Maartens   (Portsmouth)