# Congratulations for the 2022 Nobel Prize in Physics, in the area of Quantum Information

Congratulations for the 2022 Nobel Prize in Physics, in the area of Quantum Information, for Alan Aspect, John Clauser and Aston Zeilinger.

Quantum computers use qubits, rather than classical bits. This computing paradigm has a “superpower” that makes all the difference and cannot easily be simulated on a classical computer: “quantum entanglement”.

Two qubits (say, photons) can be entangled, so that if one is measured and results in 1, the other is also 1. Likewise, if one is measured as 0, the other is also 0. The draw is random, so we don’t know if it’s going to be 0 or 1 — we just know that the photons will be 100% correlated.

Then, some questions arise: if one photon is on Earth and the other is on the other side of the universe, say Alpha Centauri, how does one of the photons “know” the outcome of the other? Is there faster-than-light communication? Is there a “hidden variable”, with the draw already done in advance?

This was what Albert Einstein called “spooky action at a distance” in an attempt to say that quantum mechanics had problems.

To clarify the matter, physicist John Bell devised a test to prove that there is no “hidden variable” capable of reproducing the result of quantum mechanics.

However, one thing is to idealize a test, another thing is to actually perform it. And that’s where Nobel-winning researchers come in. They worked on increasingly complete experiments to prove the violation of Bell’s inequality, and thus to show that the entanglement effect is real.

Possible applications are in information security, quantum sensors and quantum computing.

Congratulations to the researchers, and great news for the areas mentioned!

https://www.nobelprize.org/prizes/physics/2022/prize-announcement/