American physicists in the first managed to get a substance with a "negative mass": if such a substance is accelerated, it will move in the opposite direction, reports the BBC.

In the ordinary state, if some force acts on the object, it begins to move towards this force. At the same time, theoretically, matter can have a negative mass, physicists call this phenomenon "exotic matter".

Now scientists managed to cool the atoms of rubidium almost to the absolute zero temperature (-273 degrees Celsius), having received the Boise-Einstein condensate. The rubidium atoms cooled and held the sample until the high-energy particles moved beyond the boundaries of the laser trap. At this stage, the atoms still behaved like particles with a normal, positive mass: if the force that held the atoms together ceased to function, the extreme atoms would scatter all sides under the pressure of the central.

To make rubidium atoms behave like a substance with a negative mass, another set of lasers was sent to them, with the help of which it was possible to change the spin of some atoms.

Comparing the calculated data with the experimental ones, physicists came to the conclusion that some of the atoms in the laser trap began to accelerate in the direction opposite to the application of the force of the atoms that were in the center of the trap - true, this only happened for a very short time, after which the atoms quickly returned to behavior , Characteristic of particles with a positive mass.

Earlier it was reported that scientists have discovered a new subatomic particle - pentaquark. Pentakvarki were discovered as a result of collisions of protons at energies up to 8 teraelectronvolts. The weight of the pentaquark does not exceed 4.5 gigaelectronvolts. Previously, physicists reliably knew about the existence of only hadrons (particles that consist of quarks and participate in strong interaction) from two quarks (mesons) or three (baryons).