Consciousness is the state of being awake and aware of one’s surroundings and within oneself. It is the ability to discriminate stimuli or report information. It is the tune stuck in our heart, the sweetness of a chocolate, the throbbing pain of a toothache, the fierce love for our child and the bitter knowledge that eventually all feelings will end. The origin of consciousness is one of the most intractable mysteries about the human mind, because of its intrinsic conceptual and theoretical difficulties. Besides neuro-scientists and theologians, physicists are also grappling with this problem.
In this context one cannot do without referring to the work and ideas of Sir Roger Penrose, this year’s Nobel Laureate in Physics. There is a lot about him to go through, even for the interest of lay readers and non-physicists. He has been a mathematician and must have done things algorithmically in a step by step procedure to solve the logical problems. However, in 1931, the mathematician and logician Kurt Gödel had argued that any effectively generated theory capable of expressing elementary arithmetic cannot together be consistent and complete.
A consistent formal theory may prove certain basic arithmetic truths, but then there are arithmetic truths, that are not provable in the theory. Penrose took this to mean that human mathematicians are not formal proof systems and not running a computable algorithm. So the equivocation of working of human brain on the meaning of computation was taken to be fallacious.
Taking a lead from this, Penrose argued that human consciousness is non-algorithmic in nature which cannot be modelled by a conventional Turing machine, say a digital computer. The subject has been dealt with extensively in his very first book titled, “The Emperor’s New Mind.” This book attacks the claims of artificial intelligence using the physics of computing. Artificial intelligence experts have been predicting some sort of a computer brain for decades, with little to show so far. For all the recent advances in neurobiology, we seem no closer to solving the mind-brain problem than we were a century ago. Even if the human brain’s neurons, synapses and neurotransmitters could be completely mapped—which would be one of the great triumphs in the history of science—it’s not clear that we would be any closer to explaining how this three pound mass of wet tissue generates the immaterial world of our thoughts and feelings. This is because the home of computing lies more in the tangible world of classical physics than in the imponderable realm of quantum physics. Therefore, something seems to be missing in current theories of consciousness and that is the quantum nature of mind.
The aforesaid book came in 1989 when Penrose lacked a detailed proposal for how such quantum processes could be implemented in the human brain. Subsequently, when Stuart Hameroff, an American anesthesiologist read it, he suggested to Penrose that certain structures within brain cells called (microtubules) could be suitable candidate sites for quantum processing and ultimately for consciousness. Therefore a new theory arose from the co-operation of the two scientists which was given a shape in Penrose’s second book on consciousness, titled “Shadows of the Mind“ in (1994). In some ways, Penrose and Hameroff are the odd couple of science. Hameroff is upfront about his spiritual views, talking openly about the possibility of the soul existing after death. Penrose is an atheist who calls himself “a very materialistic and physicalist kind of person.”
The concept of conscience has however brought them close on a delicate borderline. Neuroscientists have isolated specific parts of the brain that explain how consciousness happens. Attempts were made to break down the functional parts of the human brain but even after decades of mapping, no answers were found about the origin of consciousness. According to Sir Penrose, one might speculate that somewhere deep in the brain, cells are to be found of single quantum sensitivity. If this proves to be the case, then quantum mechanics will be significantly involved in brain activity. Penrose continues to say, “A lot of what the brain does, you could do on a computer. I’m not saying that all the brain’s action is completely different from what you do on a computer. I am claiming that the actions of consciousness are something different. I’m not saying that consciousness is beyond physics, either—although I’m saying that it’s beyond the physics we know now.
My claim is that there has to be something in physics that we don’t yet understand, which is very important, and which is of a noncomputational character. It’s not specific to our brains; it’s out there, in the physical world. But it usually plays a totally insignificant role. It would have to be in the bridge between quantum and classical levels of behavior—that is, where quantum measurement comes in.” The idea that a quantum effect is necessary for consciousness to function is still in the realm of philosophy. The demonstration of a quantum mind effect by experiment is necessary to ascertain this. Penrose spoke at a one-day conference on consciousness in Lucerne, Switzerland in 2016. It was an intriguing assortment of speakers, including the neuroscientist Christof Koch and Buddhist monk Matthieu Ricard. Then there was Penrose, slightly rumpled in appearance, with an impish sense of humor.
He had set up two overhead projectors on stage, and then darted back and forth between these machines, laying down a series of transparencies filled with his own handwritten notes and drawings of neurons and microtubules, all in an effort to explain his theory of consciousness. As we probe the deeper implications of Penrose’s theory, it isn’t always clear where to draw the line between the scientific and philosophical dimensions of his thinking. Quantum mechanics may have to do something with the workings of the mind. Since mind manifests the capacity to make choices, this property is to some extent inherent in every electron. One may point out if Penrose’s theory has any bearing on the long-running philosophical argument between free will and determinism.
Many neuroscientists believe that decisions are caused by neural processes that aren’t ruled by conscious thought, rendering the whole idea of free will obsolete. On the other hand, since indeterminacy is intrinsic to quantum theory, it suggests that causal connections break down in the conscious brain. Therefore Penrose is trying to make the case for free will. That talk of Penrose was more like a dazzling piece of performance art than a high tech game of modern science and the overflowing audience loved it.
Dr. Qudsia Gani is Assistant Professor, Department of Physics, Cluster University Srinagar