Binary Stars Build Dark Matter Molecules ⚡ экспресс
Ultralight bosons (like axions) around binary stars can form gravitational 'molecules.' Simulations show that as the stars draw closer, they shed particles (ionize), and this process in the early stages affects the orbit more strongly than gravitational waves, creating a kink in their spectrum. Interestingly, the inner part of the molecule ionizes solely due to the orbit's ellipticity, gradually making it circular — much like a wobbly wheel that becomes rounder over time from friction.
A pair of stars whirling in elongated orbits acts like a giant nucleus, and the cloud of dark matter around them—like an electron cloud in a molecule. This 'gravitational molecule' stretches billions of kilometers—more than from the Sun to Pluto. Its size is determined by an analog of the Niels Bohr radius, familiar from the hydrogen atom.
The motion of the stars shakes this cloud, ripping particles out of it—a process similar to atomic ionization. Due to the loss of particles, the pair's orbit gradually rounds: the ellipse becomes a circle. Notably, in the early stages, this effect can surpass the emission of gravitational waves, leaving a characteristic kink in their background.
🎯 The radius of such a 'gravitational molecule' can exceed the distance from the Sun to Pluto, even though the very concept of a radius comes from the microworld.