Quanta Of Space

To measure a volume of space, it is necessary to place a particle in it.
According to Heisenberg's uncertainty principle, a particle placed at a point in space soon escapes from it.
The smaller the volume, the greater the velocity of the escape.
A particle escaping at a high velocity has a lot of energy.
A lot of energy in a small volume of space curves space so much that the particle becomes a black hole.
Thus, the attempt to measure a small volume of space prevents measurement of it.
The minimum volume of space is the minimum size of a particle before it becomes a black hole.
-Carlo Rovelli, Reality Is Not What It Seems (Allen Lane, 2016), pp. 129-130.