Heh.
Fascinating about that density thing, wow.
To put my nerdiness fully on display, white dwarf matter is by far not the densest material in the universe. That goes to neutron degenerate matter, which makes up neutron stars. 100 million tons per cubic centimeter. A mountain in a thimble. It’s what happens when a white dwarf star exceed 1.4 times the mass of the sun, and electron degeneracy fails, which always results in a supernova. Any denser than that and you have a black hole, of hypothetically infinite density. Not theoretical because our laws of physics don’t apply there.