Schrödinger’s cat survives 23 minutes, new record in quantum physics

In the world of quantum physics, another record has just been broken: the famous Schrödinger’s cat paradox lasted for 23 minutes. This was reported by researchers from the University of Science and Technology of China on the pages of the preprint site ArXiv. The report reveals that the ability to maintain stable states for so long could support the creation of quantum devices and the discovery of strange new effects in physics.

Schrödinger’s cat helps you understand

Devised by Austrian physicist Erwin Schrödinger in 1935, Schrödinger’s cat is a thought experiment that sought to simplify the particularities of quantum mechanics.the branch that studies very small spatial scales, to understand them better. Newton’s classical physics built an objective and realistic image of the world, however, at the beginning of the 20th century it was discovered that subatomic matter did not obey these laws. According to quantum mechanics, subatomic particles exist in multiple states at once.

To test it, Schrödinger devised a scenario in which a cat was placed in a box with lethal poison, and next to it, a hammer connected to a light sensor. When the sensor was activated, the hammer would release and break the bottle. Under these conditions, the sensor would detect the feline, the hammer would break the container, the poison would spread throughout the box and kill it. On the other hand, if the electron were deflected, the sensor would not detect it and the cat would survive. The conditions are so special that, according to the laws of quantum physics, it would be impossible to know if he is alive or dead.

‘Life or death’ were typically fragile and fleeting assumptions, in which it was theorized that an object could be in various states without knowing which one it actually occupied. In other words, it occupied them all simultaneously. For years, researchers replicated Schrödinger’s experiment with light particles and even small crystals in the laboratory, but these practices were always very unstable and extremely fleeting.

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The 23 minute paradox

In the new study led by physicist Zheng-Tian Lu, Atoms trapped by light were used to maintain the phenomenon for an exceptionally long time. They used about 10,000 ytterbium atomswhich they cooled to thousandths of a degree above absolute zero and trapped with the electromagnetic forces of laser light. Under these conditions, the quantum states of atoms could be controlled very precisely, and the researchers took advantage of this by placing each atom in a superposition of two states that had two very different spins.

Normally, perturbations to the atoms’ environment would cause them to collapse into a single state within seconds or milliseconds, but the scientists managed to tune the lasers just to keep them running for an unprecedented 1,400 seconds, or 23 minutes. Due to such a long duration, such a phenomenon could not only be used to detect and study magnetic forces or to probe new and exotic effects in physics, but it could become a very stable memory capable of storing and processing quantum information.

“It’s a great achievement because they created this beautiful paradox in an atomic system that is stable. In the future, it could be used to investigate new and exotic effects in fundamental physics,” Barry Sanders of the University of Calgary told the magazine New Scientist.

Article originally published in WIRED Italy. Adapted by Alondra Flores.