How quantum fog tests the laws of gravity ⚡ экспресс
Analytically and numerically, we investigate the ground state and collective dynamics of Bose-Einstein condensates in two traps: Newtonian and logarithmic, based on modified Newtonian dynamics (MOND). In the ground state, the MOND potential yields bound states only in the deep MOND regime, and the condensate is notably larger than its Newtonian counterpart. Size growth with the repulsive parameter β is observed in both cases, but only in the MOND trap is scaling R ~ β^{1/3} revealed, confirmed numerically over a wide range; for the Newtonian trap, no simple law emerges due to the breakdown of the Thomas–Fermi approximation. Analysis of monopole collective excitations shows that the oscillation frequency of the MOND condensate is lower and, in the strong interaction limit, decreases as β^{-1/3}. The results are important for designing experiments on quantum simulation of modified gravity with cold atoms.
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.