[Rockhounds] Scientists Uncover the Universal Geometry of Geology

[Kreigh Tomaszewski]

n a mild autumn day in 2016, the Hungarian mathematician Gábor Domokos
<http://bagira.iit.bme.hu/~domokos/> arrived on the geophysicist Douglas
Jerolmack <https://earth.sas.upenn.edu/people/douglas-j-jerolmack>’s
doorstep in Philadelphia. Domokos carried with him his suitcases, a bad
cold and a burning secret.

The two men walked across a gravel lot behind the house, where Jerolmack’s
wife ran a taco cart. Their feet crunched over crushed limestone. Domokos
pointed down.

“How many facets do each of these gravel pieces have?” he said. Then he
grinned. “What if I told you that the number was always somewhere around
six?” Then he asked a bigger question, one that he hoped would worm its way
into his colleague’s brain. What if the world is made of cubes?

At first, Jerolmack objected. Houses can be built out of bricks, but Earth
is made of rocks. Obviously, rocks vary. Mica flakes into sheets; crystals
crack on sharply defined axes. But from mathematics alone, Domokos argued,
any rocks that broke randomly would crack into shapes that have, on
average, six faces and eight vertices. Considered together, they would all
be shadowy approximations converging on a sort of ideal cube. Domokos had
proved it mathematically, he said. Now he needed Jerolmack’s help to show
that this is what nature does.

“It was geometry with an exact prediction that was borne out in the natural
world, with essentially no physics involved,” said Jerolmack, a professor
at the University of Pennsylvania. “How in the hell does nature let this
happen?”

https://www.quantamagazine.org/geometry-reveals-how-the-world-is-assembled-from-cubes-20201119/