Remarks on the maximum luminosity

Understand

The quest for fundamental limitations on physical processes is old and venerable.

• Here, we investigate the maximum possible power, or luminosity, that any event can produce.
• We show, via full nonlinear simulations of Einstein's equations, that there exist initial conditions which give rise to arbitrarily large luminosities.
• However, the requirement that there is no past horizon in the spacetime seems to limit the luminosity to below the Planck value, ${{\cal L}_\textrm{P}\!=\!c^5/G}$.