Electronica, physics, science scottishnatureboy
The Oppenheimer Snyder solution

From a podcast of the BBC Radio 4's science show, The Infinite Monkey Cage, I gleamed a tiny and purely qualitative view of a scientific concept that allows for the physics of Dr Who's TARDIS. Namely, the Oppenheimer-Snyder solution of Einstein's General Relativity equations allow for a TARDIS, a finite region of spacetime in which a much larger region is contained. As they say on the Dr Who show, "It's bigger on the inside"!

To quote from t'Internet: "In their classic 1939 paper, OPPENHEIMER & SNYDER introduced the first mathematical model for gravitational collapse of stars based on spherically symmetric solutions of the Einstein gravitational field equations. In this pioneering paper, OPPENHEIMER& SNYDER gave the first rigorous results describing gravitational collapse of stellar objects, and the remarkable conclusion of this work was that "black holes" could form from gravitational collapse in massive stars."