This density of 10^93 gm/cm^3 is computed by dividing the Planck Mass by the Planck Volume. The result is a combination of pure physical constants...c...G...h.

The numerology of this quantum domain has it that no higher densities are possible because there is no way to create such densities without them becoming black holes.

One interesting issue is observability. If you tried to probe the plank scale with a photon of light to capture its reflection, you would have to have a photon with a wavelength of 10^-33 cm. But such a photon would carry enough energy for it to instantly become a quantum black hole. The interaction region you are trying to study would then be instantly surrounded by an event horizon so that ypou would not be able to receive any information about what properties it had, defeating your whole plan to try to observe it in the first place!!!

The truth is that no one really knows anything about these conditions in any pragmatic way, and the theoretical ideas, called Quantum Gravity Theory are not well developed yet...if they ever will be!.

Return to Dr. Odenwald's Gravity page at the Astronomy Cafe Blog.