Researchers in Switzerland have devised an experiment that would allow humans to directly perceive quantum entanglement for the very first time. Quantum entanglement occurs when two particles, at the quantum scale, interact in a way in which they become linked, demonstrating that ‘space’ might just be the construct that gives the illusion of separation between two physical objects. That being said, the behavior of particles at the quantum scale does not mimic the behavior of physical systems that are much larger.
If we think in terms of a cosmic scale explanation, two electrons created together are entangled; if we send one to the other side of the universe and then do something to one of them, like spin it, the other will mimic the behaviour instantaneously. This means either that information is travelling faster than the speed of light, or, again, that the vast distance we perceive between objects really doesn’t exist at all.
Quantum entanglement has been verified, meaning that physicists can entangle light particles in a laboratory setting, but the researchers from Switzerland want to take it one step further. As ScienceAlert reports, “The premise is that the human eye is basically a photon detector, so, in theory, we should be able to replace the photon detecter in an entanglement detecting experiment with a human eye, and use people to observe the process instead.”
Sadly, it’s not going to be easy, MIT Technology Review reveals:
The main problem is that the eye cannot detect single photons. Instead, each light-detecting rod at the back of the eye must be stimulated by a good handful of photons to trigger a detection. The lowest number of photons that can do the trick is thought to be about seven, but in practice, people usually see photons only when they arrive in the hundreds or thousands.Even then, the eye is not a particularly efficient photo-detector. A good optics lab will have photo-detectors that are well over 90 percent efficient. By contrast, at the very lowest light levels, the eye is about 8 percent efficient. That means it misses lots of photons.
Basically, for someone to be able to see this happen, thousands of quantum entangled photons have to be firing, which isn’t possible with today’s technology. Or is it?
A device called a beam splitter could be used, according to the researchers in Switzerland:
A beam of coherent photons from a laser is aimed at a splitter, transmitted through it, but then a change of phase causes it to be reflected. If a second laser beam interferes with the first, it will change the phase of the first beam—reflecting it back instead of passing through the splitter. So the second beam controls whether the first is reflected or not. This “switching beam” does not need to be as powerful as the main beam, but it does need to be coherent—that is, an actual laser—to make this successful.
Even with a beam splitter, one would have to sit down and watch thousands of experiments…
If you’re still confused about how quantum entanglement works, you can watch this video of Derek from Veritasium.
Below is another excellent visual from Dr. Quantum, as seen in the film What The Bleep: Down The Rabbit Hole.