So, what is consciousness? How does it work? What is quantum mechanics? Can you explain these things?
Richard Feynman, the popular American physicist explained about the notorious puzzles as below:
“I cannot define the real problem, therefore I suspect there is no real problem, but I am not sure there is no real problem.”
These puzzles and paradoxes are also about quantum mechanics. We know it as the theory used by physicists to describe objects in the Universe. But, we do believe that here he has been talking about the same problem; consciousness.
Additionally, some scientists think that we understand about consciousness, by saying it is like a mere illusion. But, others feel that we do not understand about consciousness yet. The puzzle then led some researchers to invoke quantum physics. Even though, it is not wise to explain a mystery with another. On the other hands, doing this way is not absurd.
Still, it is the best theory to describe atoms and subatomic particles in the world. The biggest mystery about this theory is the outcome of how a quantum experiment can change depends on whether or not we choose to measure some property of the particles. Now, the question is; If the world behaves depends on how we look at it, so what does reality mean?
At that point, researchers forced to say that objectivity was an illusion, and therefore consciousness has to be allowed an active role, related to quantum theory. But for others, this is not reasonable. So, Albert Einstein once complained about the moon that does not exist only when we look at it.
Quantum Mechanics and Consciousness
Even today, some physicists suspect that consciousness influences or not influence quantum mechanics. They also think that quantum theory is important to learn so we can fully understand how our brain works.
When there is an argument saying that quantum objects can b in two places at the same time, is it possible if a quantum brain can hold two mutually exclusive ideas at once?
The Double-Slit Experiment
The double-slit experiment becomes one of the most mind-blowing things about quantum mechanics. So, if you are shining a beam of light at a screen with two closely-spaced parallel slits, then some of the light can pass through the slits while others strike another screen.
At this point, we can say that light is a kind of a wave. Waves that emerge from two slits can interfere with each other. They can reinforce each other if their peaks coincide. Whereas, they cancel out if a peak and a trough coincide. We call this interference as diffraction to produce a series of alternating bright and dark stripes on the back screen, where the light waves are reinforced or canceled out.
In this experiment, we could understand the characteristic behavior since 200 years ago. At that time, we did not even see the quantum theory. Also, the double slit experiment could be performed with the quantum particles, like electrons. So, these particles can behave like waves. They undergo diffraction when a stream of them passes through the two slits and produces the interference pattern.
The strange thing is that if we place a detector inside or behind one slit, we can find whether there is any given particle goes through it or not. The interference vanishes. So, observing a particle’s path even though there is nothing that disturbs the particle’s motion, can change the outcome.
Back in the 1970s, Jon Wheeler, the popular American physicist proposed an experiment for doing this. What he did was clever techniques with the goal to make measurements on the path of quantum particles like particles of light, named photon. The finding was there was no difference whether we delay the measurement or not. We can lose all interference if we measure the photon’s path before its arrival at the detector. It is like nature “knows” not just if we are looking, but if we are planning to look.
Consciousness and Quantum Mechanics Are Somehow Linked
The Hungarian physicist, Eugene Wigner admitted this possibility in the 1930s. He wrote that the quantum description of objects is influenced by impressions entering my consciousness. Even though physicists still do not agree about the best way to interpret these quantum experiments, in one way, it is hard to avoid that consciousness and quantum mechanics are linked.
Then, it was in the 1980s, the British physicist, Roger Penrose suggested that the link probably works in the other direction. Perhaps, quantum mechanics is involved in consciousness. Also, Penrose wondered about the presence of molecular structures in our brains that can alter their state in response to a single quantum event. Can these structures work as particles in the double slit experiment?
In fact, the human brain can handle the cognitive process that is still far exceeding the capabilities of digital computers. Penrose then proposed the quantum effects feature in human condition from his book in 1989. From his book, Penrose believed that the collapse of quantum interference and superposition is a physical and real process. In the end, the ideas about quantum effects in the brain were nothing, unless the great skepticism to see. The idea that the brain employs quantum tricks does not show any signs.
A physicist named Matthew Fisher then published his study in 2015. He studied at the University of California and he argued that the brain might contain molecules for sustaining more robust quantum superposition. He talked about the phosphorus nuclei that have a quantum property called spin. Also, Fisher said that the quantum-mechanical behavior o the nuclear spins cold resist decoherence on human timescales. Additionally, Fisher argued that phosphorus spins could resist decoherence. In other words, they can influence how our brain works.
Adriant Kent is one of the most respected quantum philosophers and he speculated that consciousness might alter the behavior of quantum systems, back in 2016. One big question is how our conscious minds experience unique sensations like the smell of frying bacon. We call this sensation as qualia and it is the product of our consciousness and that is not easy to explain.