Abstract
The optical appearance of gas inside and emerging beyond the Schwarzschild sphere is studied. We emphasize the importance of taking into account photons moving with nontrivial angular momentum. A semiqualitative analysis shows that no spectral lines could be seen by a distant observer if gas emits from a region near the Schwarzschild sphere. On the basis of our analysis we suggest that quasars and BL Lac objects are somewhat different manifestations of the same physical process, namely, a white hole expansion.
