Naked Singularities as Possible Candidates for Gamma-ray Bursters
  Naked singularities appear naturally in dynamically evolving solutions of Einstein equations involving gravitational collapse of radiation, dust and perfect fluids, provided the rate of accretion is less than a critical value. We propose that the gamma-ray bursters (GRBs) are examples of these naked singularity solutions. For illustration, we show that according to solutions involving spherically symmetric collapse of pure radiation field, the energy $E_\gamma$ and the observed duration $\Delta t_o$ of a GRB should satisfy, $\frac{E_\gamma}{\Delta t_o} \leq 4.5 \times 10^{58} \ f_\gamma $ erg sec$^{-1}$, $f_\gamma$ being the fraction ($10^{-2}$ to $10^{-3}$) of energy released as gamma rays. All the presently observed GRBs satisfy this condition; those satisfying the condition close to equality must necessarily be of cosmological origin with the red-shift factor $z$ not exceeding $\sim 2-10$ depending on exact observed flux. 
Sandip K. Chakrabarti and Pankaj S. Joshi (Tata Institute of   Fundamental Research, Bombay, India)