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Loophole-free Bell test

In 1935, Einstein asked a profound question about our understanding of Nature: are objects only influenced by their nearby environment? Or could, as predicted by quantum theory, looking at one object sometimes instantaneously affect another far-away object? Einstein did not believe in quantum theory’s prediction, famously calling it “spooky action”.
Exactly 80 years later, a team of scientists led by professor Ronald Hanson from Delft University of Technology finally performed what is seen as the ultimate test against Einstein’s worldview: the loophole-free Bell test. The scientists found that two electrons, separated 1.3 km from each other on the Delft University campus, can indeed have an invisible and instantaneous connection: the spooky action is real.

 

‘Spooky action at a distance’, no cheating.'

The experiment, published in Nature today, breaks the last standing defence of Einstein’s iconic 1935 paper: it closes all the loopholes present in earlier experiments. The Delft experiment not only closes a chapter in one of the most intriguing debates in science, it may also enable a radically new form of secure communications that is fundamentally impossible to ‘eavesdrop’ into.

All information about the Bell test can be found here

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Nature
TU Delft

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