Chladni figures are the beautiful geometric patterns appearing when a plate covered with a small amount of sand (or other fine powder) is allowed to vibrate at certain frequencies. The following is an example of this phenomenon.

Depending on the vibration frequency, certain areas of the plate are not experiencing any vibrations (waves cancel each other in these areas). The sand is pushed from vibrating areas and accumulates in these quiet areas, producing the patterns.

Galaxy filaments are the largest structures in the universe (hundreds of millions of light-years). They are made up of galaxies (and clusters of galaxies). These filaments create boundaries, or walls, enclosing large voids where there is practically no matter.

By Richard Powell (http://www.atlasoftheuniverse.com/nearsc.html) [CC BY-SA 2.5 (https://creativecommons.org/licenses/by-sa/2.5) ], via Wikimedia Commons

These filaments are believed to be the result of dark matter interacting with visible matter, which seems to be confirmed by computer simulation.

WARNING: Wild speculations below.

If galaxies in the universe are akin to grains of sand on a plate, the observed pattern  looks like 3D Chladni figures. Could it be that vibrations in the fabric of the universe are forcing matter (i.e. galaxies) to settle in quiet zones, like grains of sand on a plate?