Quantum Entanglement Demonstrated in an Experiment

A group of physicists has recently carried out a series of experiments that may provide additional insight into the nature of quantum entanglement.

Famed physicist Albert Einstein famously referred to this property of quantum physics as “spooky action at a distance,” due to the instant nature of the connections it establishes between particles.

In quantum physics, entanglement is a property that refers to two particles sharing a connection over distance. In other words, if the properties of one member of the pair is changed, the other member changes instantly.

This can theoretically take place over incredible distances, as for example from one galaxy to another, and what's interesting is that the change take place instantly.

Physics experts have been trying to probe this phenomenon in great detail, but establishing experimental setups to test theoretical predictions on the matter is proving to be very difficult.

In past studies, scientists have demonstrated that entanglement indeed occurs between particles, but failed to show that the same holds true for galactic-scale distances.

In the recent investigation, what researchers did was probe the strength of quantum entanglement connecting four particles together, LiveScience reports.

They subjected the system to disturbing conditions, in a bid to learn more about the factors that were needed to break the entanglement.

Such studies are extremely important for both particle physics and the electronics industry. For the latter, understanding entanglement could open the way to fast quantum computers.

Scientists from the Institute of Experimental Physics at the University of Innsbruck, in Austria, entangled four calcium ions for the experiments.

This was done by making the ions (positively charged atoms) move in a very strict pattern, and then subjecting them to laser light that had been especially calibrated for the job.

The entire system was then exposed to an environment featuring “noise” such as other laser beams, that could potentially disrupt the quantum connection.

“We found that as you introduce noise there is a point where you can still have entanglement, but noise interferes with the useful properties of entanglement,” says Institute expert Julio Barreiro.

“The environment causes these correlations to decay,” he adds. Barreiro is also the lead author of a new study detailing the findings, which was published online in the journal Nature Physics.