Reconsidering maximum luminosity

Understand

The suggestion that there is a maximum luminosity (maximum power) in nature has a long and somewhat convoluted history.

• Though this idea is commonly attributed to Freeman Dyson, he was actually much more circumspect in his views.
• What is certainly true is that dimensional analysis shows that the speed of light and Newton's constant of gravitation can be combined to define a quantity P_* = c^5/G_N with the dimensions of luminosity (equivalently, power).
• Then in any physical situation we must have P_{physical} =$\wp$ P_*, where the quantity $\wp$ is some dimensionless function of dimensionless parameters.