In a recent experiment, Chinese researchers have succeeded in sending quantum information (also known as quantum displacement) between two tangled particles through seawater. This is the first time we have been able to perform underwater quantum communications.
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In this test, information was transmitted 3.3 meters away in a saltwater tank. Based on this success, the researchers believe it is possible to apply the technique under normal seawater conditions to transmit encrypted, untraceable information over 900 meters away.
This means a lot, it opens up for us an extremely secure means of transmitting, and is perhaps the most secure message encryption available today.
Quantum disorder or quantum entanglement means that somehow two matter particles are connected together, whatever happens to particle A will have the same effect on particle B, no matter how far apart they are. For hundreds or even thousands of light-years together, they continue to bond.
Based on that phenomenon, scientists have experimented with transmitting information by making one particle rotate according to certain laws and make the other also rotate. They hope this method can help to transmit information over large distances safely.
Previously, scientists have successfully tested quantum displacement in space, from Earth to satellites and vice versa, but this is the first time someone has done it in water, anything. What goes through this environment is also scattered.
In this test, researchers at Shanghai Jiaotong University took seawater, which it filled a 3-meter tank. They shoot a ray of light through a crystal to create a tangled pair of photons. No matter how polarized one photon is, the other photon will automatically reverse bias. The scientists placed two photons in a pair that were placed at the ends of the seawater tank. The results showed that two photons can transmit information to each other with up to 98% accuracy, which means that the method of transmitting quantum information and building an underwater quantum communication network is completely feasible. .
More tests still need to be done to study whether underwater quantum displacement works in natural environments, and how far away it can be.
Chinese scientists estimate the maximum distance that can be transmitted will be 885m. Meanwhile, as expected by another team, the maximum distance is only 120m.
As seawater absorbs light, it will be difficult to extend the distance, said Jeffrey Uhlmann, a physicist at the University of Missouri, Columbia.