How quantum fog tests the laws of gravity ✎ express

Original: "Ground State and Collective Modes of Bose-Einstein Condensates in Newtonian and MOND-inspired gravitational potentials"
· Ning Liu
arXiv:2601.01039v1 · 2026-01-03 · arXiv non-exclusive · independent analysis · 1 min
An ultracold atomic cloud behaves differently if gravity changes over large distances.

📄 Showing the "Simple" version — "Advanced" is not ready yet. Add it to favorites to help prioritize it.

An ultracold atomic cloud, resembling fog, hints that gravity might not work as Newton said. On the outskirts of galaxies stars move faster than expected, and MOND theory tweaks the law of gravitation over large distances, removing the need for dark matter. When such a fog was placed in a MOND trap, it puffed up more and wobbled slower. A simple pattern emerged: if the repulsion between atoms increases 8-fold, the cloud's size grows only twofold (cube root). The oscillation frequency drops similarly. In a Newtonian trap, there's no such clear pattern. The lab fog unexpectedly became a mini proving ground for testing the standard model of cosmology. Turns out, to study galaxies, you don't need a telescope — just a droplet on a table.

The temperature of such a fog is one of the lowest in the Universe: billions of times colder than deep space.

R \propto \beta^{1/3}
R — cloud size, β — atomic repulsion strength
Scientists
Erwin SchrödingerHugh Everett IIIFritz ZwickyIsaac NewtonGalileo GalileiJohannes Kepler
Concepts
Bose-Einstein condensate modified newtonian dynamics condensate condensation newtonian limit Gross–Pitaevskii equation boltzmann entropy Bose–Einstein statistics squeezed state newtons laws dark matter modified gravity ground state Newton's second law Bekenstein bound bound state vacuum