15,842 new words: I would be a very small black hole.

Enter that room and you breached a Schwarzschild radius of something not canny, and that cephalopod corpse was the singularity.

-- Kraken, China Mieville.

The Schwarzchild radius is the radius of the hypothetical sphere of matter within which you would have to condense that matter sufficiently to create a gravitational field in which the escape velocity is the speed of light; in other words, it's the size of a black hole for any given amount of matter.

The Schwarzchild radius for the sun is 3 km; condense the sun to that size, and you have a black hole. For Earth, and this is fascinating to me, the radius is 9 mm.  The Schwarzchild radius for me is 1.738 x 10^-25 m.

Currently, the smallest black hole known to man is 24km in diameter.  Scientists theorize there may be a far smaller one, but Donald Trump wouldn't release his medical records.