Spooky action

New quantum research shows two objects can instantly interact, even if separated by huge distances.

“God does not play dice with the universe.” With this famous line, Albert Einstein dismissed one of the most fundamental claims of quantum theory — namely, that objects that are far apart from each other can instantaneously affect each other’s behaviour. This is often called the entanglement theory.

Now, scientists at the Delft University of Technology in the Netherlands appear to have come out with a definitive demonstration that the entanglement principle does in fact exist, reports the international edition of The New York Times.

The new research serves yet another blow to the theory of “locality,” which is fundamental to classical physics. Under this principle, an object can be influenced only by phenomena in its immediate surroundings. With entanglement theory, on the other hand, two objects can still instantaneously interact even though they might be separated by huge distances. Einstein called this “spooky action at a distance.”

Entanglement is one of the most fundamental tenets of the theory of quantum mechanics, which relates to what The New York Times calls an “odd world formed by a fabric of subatomic particles, where matter does not take form until it is observed and time runs backward as well as forward.”

Many experiments since the 1970s have tried, more or less convincingly, to prove that “entanglement” exists. But most of the time, some variable or other could be explained by referring to notions of classical physics. The Delft University researchers have devised a “loophole-free” experiment ruling out any hidden variable that could be explained away based on classical physics laws.

Two diamonds containing minuscule traps for single electrons were set 1.3 kilometres apart, each monitored by detectors. The distance ensured it was impossible for information to be exchanged by conventional means within the time needed to effect measurements. Pulses of microwave and laser energy were then shot at one of the particles to impart in it a magnetic “spin”. The other particle, 1.3 kilometres away, spun at the same time.

As lead researcher Ronald Hanson noted, “Now we have confirmed that there is spooky action at distance.”