Emission from charged white holes

Narlikar and Apparao derived the spectral properties of electromagnetic radiation emitted in the radial direction from an expanding spherically symmetric white hole containing uncharged dust. The formula is generalized here so as to be applicable to a spherical white hole containing charged fluid. Although the formula can be applied to any spherically symmetric solution of Einstein-Maxwell equations, a specific solution discovered by Banerjee, Chakravarty and Dutta Choudhury is considered. Certain inaccuracies in the derivations given by earlier workers are also pointed out. (author)