Perhaps one of the most intriguing and interesting phenomena in quantum physics is what Einstein referred to as a "spooky action at a distance" — also known as quantum entanglement. This quantum effect is behind what makes quantum computers work, as quantum bits (qubits) generally rely on entanglement to process data and information. It's also the working theory behind the possibility of quantum teleportation.
The long and short of it is this: entangled particles affect one another regardless of distance, where a measurement of the state of one would instantly influence the state of the other. However, it remains "spooky" because — despite following the laws of quantum physics — entanglement seems to reveal some deeper theory that's yet to be discovered. A number of physicists have been working on determining this deeper theory, but so far nothing definitive has come out.
As for entanglement itself, a very famous test was developed by physicist John Bell in 1964 to determine whether particles do, in fact, influence one another in this way. Simply put, the Bell test involves a pair of entangled particles: one is sent towards location A and the other to location B. At each of these points, a device measures the state of the particles. The settings in the measuring devices are set at random, so that it's impossible for A to know the setting of B (and vice versa) at the time of measurement. Historically, the Bell test has supported the spooky theory.
Human Consciousness and Free Will
Now, Lucien Hardy, a theoretical physicist from the Perimeter Institute in Canada, is suggesting that the measurements between A and B could be controlled by something that may potentially be separate from the material world: the human mind. His idea is derived from what French philosopher and mathematician Rene Descartes called the mind-matter duality, "[where] the mind is outside of regular physics and intervenes on the physical world,” as Hardy explained.
To do this, Hardy proposed a version of the Bell test involving 100 humans, each hooked up to EEG headsets that would read their brain activity. These devices would be used to switch the settings on the measuring devices for A and B, set at 100 kilometers apart. "The radical possibility we wish to investigate is that, when humans are used to decide the settings (rather than various types of random number generators), we might then expect to see a violation of Quantum Theory in agreement with the relevant Bell inequality," Hardy wrote in a paper published online earlier this month.
If the correlation between the measurements don't match previous Bell tests, then there could be a violation of quantum theory that suggests A and B are being controlled by factors outside the realm of standard physics. “[If] you only saw a violation of quantum theory when you had systems that might be regarded as conscious, humans or other animals, that would certainly be exciting. I can’t imagine a more striking experimental result in physics than that,” Hardy said. “We’d want to debate as to what that meant.”
What it could mean is this: that the human mind (consciousness) isn't made up of the same matter governed by physics. Furthermore, it could suggest that the mind is capable of overcoming physics with free will. This could potentially be the first time scientists gain a firm grasp on the problem of consciousness. “It wouldn’t settle the question, but it would certainly have a strong bearing on the issue of free will,” said Hardy.