Scientists first observed quantum paradox Cheshire cat
Physicists from France, Austria and the United States at the Institute Laue-Langevin (Grenoble, France) turned out to experiment, in consequence of which they measured the magnetic episode of the neutron regardless of the provisions of the neutron.
The phenomenon that was observed by scientists, is called phenomenon Cheshire cat. The results of their own experiences of the authors published in the journal Nature Communications.
Scientists divided the neutron beam at 2 depending on the orientation of the spins of the particles in them: directions 1 coincided with the direction of the external magnetic field, others were opposite to him. In consequence of a series of measurements, including feeble measure, the scientists in one of the beams had managed to trace the tracks of particles (to measure the neutron polarization in a magnetic field) from another, as if they were there.
Hilo measurement in quantum mechanics is a small perturbation of particles measured by the device. But this method of extraction of the observed mean low accuracy of the results of measurements and, as a consequence, many of measurements, which managed to provide a powerful source of neutrons at the Institute Laue-Langevin.
In their experiment applied physics of neutron interferometer - a device that allows you to watch wave characteristics neutral nucleon: a single neutron beam passes through the interferometer, where is divided into 2 that interfere between themselves and lead to the formation of a suitable picture. Based on the beliefs of quantum mechanics, this is a manifestation of corpuscular-wave dualism, in which the wave characteristics are connected with the imposition of de Broglie waves - a superposition of the wave functions of particles. With all this significantly classic notion of the line of motion of a particle loses value: a neutron can be at the same time in 2 beams.
Theoretical idea about fenomene the Cheshire cat appeared not long ago and boils down to the fact that the characteristics of some object can be defined (measured observed particles), where it is not. In traditional physics it is unrealistic in consequence of the principle of legality, according to which in addition to the object of its characteristics can be based only on his close encirclement.
In quantum mechanics the situation is different: quantum entanglement implies that subsystem previously unified after explode on their distance from each other continue to have a mutual influence. Consideration relating to the principle of locality and quantum entanglement takes different forms, on the basis of the interpretation of quantum mechanics.
The Cheshire cat is considered to be one of their heroes tales of the British author and mathematician Lewis Carroll "Alice in Wonderland". The animal could disappear and leave on his own place of your smile. Scientists believe that the use of the phenomenon of the Cheshire cat can help in the creation of future high-precision metrological devices, quantum devices with a low degree of interference occurring as the consequence of the probabilistic nature of the measurements.