1916: Schwartzchild radius - The book of science

Schwartzchild radius
Singularity
Flexibility
Commentary

Schwartzchild radius

The first exact solution
of general relativity
for a single spherical non-rotating mass
led to the derivation
of the gravitational radius,
associated with every quantity of mass,
and the event horizon
of a non-rotating black hole.

Singularity

A point in spacetime at which matter
has infinite density and infinitesimal volume.
All matter of the universe in less than a dot
less than a moment before the big bang.
The future time when computer intelligence
becomes capable of improving itself.
The myth of individual uniqueness,
also known as the Lake Wobegon syndrome.

Flexibility

There might come a time
when all that you know and love
dissolves, and your challenge
would be to rely on whatever
makes you human. You would
need to gather whatever is left
and make another life, somewhat,
inescapably, like the life before.

The Schwartzchild solution relates the radius to time, the speed of light, the mass, and the gravitational constant. Schwartzchild derived this radius from the Schwartzchild solution, otherwise known as the Schwartzchild metric and the Schwartzchild vacuum. It describes the radius of the event horizon of a Schwartzchild black hole.

The year after Schwartzchild solved the problem, Johannes Droste independently found a simpler solution.