In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

A covariant bound on this quantity proposed by Raphael Bousso is defined in terms of this quantity's value on light-like hypersurfaces chosen so that the generating null geodesics have non-positive expansion. One argument against white holes' existence in our universe is the significantly lower value for this quantity they have than their black counterparts. The maximum value for this quantity in a region of radius R is equal to 2pi R times Boltzmann's constant times energy enclosed divided by h-bar times c, according to a bound put forth by Jacob (*) Bekenstein. The equality case in the Bekenstein bound is achieved by black holes, for which this quantity is proportional to area, as suggested by the observation that event horizons generally only grow in size. For 10 points, identify this quantity whose non-decrease is the subject of the second law of thermodynamics.
Science