Scientists reveal the secret to track the unobserved movement of quantum particles
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Scientists reveal the secret to track the unobserved movement of quantum particles

Physicists from the University of Cambridge have been able to carve out a seemingly impossible way to keep a track of the mysterious quantum particles even during the period when they aren’t under observation. In general, we know that any object occupies only one state of being at a single go. Say, for example, something could be either alive or dead, but not both at the same time. However, quantum physics which is a base to know how life works at our subatomic level isn’t so innate.

Quantum physics is different from our basic physics where objects can exist in two different states at the same time. This means that objects have the ability to exist in both waves and particle state at the same time.  The objects after being measured can either exist as one or the other. Now, with the latest study, the scientists from the University of Cambridge have been successfully able to display the movements of those particles without having to measure them beforehand. This can be done by observing the pattern the particles follow when interacting with the surrounding environments. The results of this new study were published in the scientific journal known as Physical Review A.

To better understand this, let’s think of Schrodinger’s cat. This is a standard paradox that majorly explains the aspects of quantum theory. In this theory, a cat is closed inside a box with a vial of poison. Now, as long as we can’t see inside it, it is difficult to determine the exact status of the cat, i.e., either it is dead or alive. To confirm either of the states, we need to take a peek inside the box. To deal with this case, the researchers have come up with a way to track the exact state of the quantum object to know if it is either a particle or a wave (either dead or alive) without having to actually observe it.

David Arvidsson-Shukur, a Ph.D. student at Cambridge’s Cavendish Laboratory and author of the study described in a statement, “This premise [of Schrödinger’s cat], commonly referred to as the wave function, has been used more as a mathematical tool than a representation of actual quantum particles. That’s why we took on the challenge of creating a way to track the secret movements of quantum particles.”

As any particle interacts with its surroundings, it leaves behind a ‘tag’ that results in information that gets encoded into the particles of the object. Arvidsson-Shukur along with his colleagues came up with a way that enabled physicists to map the interactions of quantum particles with their surrounding environment without having to trace the particles directly.

The Schrodinger’s cat has proved to be good for more than just an abstract theory. The wavefunction of any quantum object is closely associated to the actual state of the particles. This has enabled the physicists to pin down the exact path of quantum particles without having to observe the forbidden domain of quantum mechanics.

Counterfactual communication is another hypothetical scenario used by scientists to jot down quantum principles. Under this theory, information can be exchanged between two people generally named as Alice and Bob, without any particles having to travel between the space lying amidst them. This concept is similar to telepathy. This theory is counterfactual as the traditional facts would state that the particles need to travel between Alice and Bob to help the message reach from one point to the other.

Arvidsson-Shukur said during a press release,” To measure this phenomenon of counterfactual communication, we need a way to pin down where the particles between Alice and Bob are when we’re not looking. Our ‘tagging’ method can do just that.”

The scientists believe that this new technique might greatly help physicists track the movement of the particles as they experiment through the whole process without having to measure them until the end of the study.