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This is a book review by two physics professors titled “Quantum Enigma: Physics Encounters Consciousness.” I argue that to understand quantum mechanics you need to understand the difference between science, metaphysics and philosophy.
Human beings have the drive to know and understand everything, and there are two research methods that stand side by side as equals: metaphysics and science. Quantum Enigma: Physics Meets Consciousness shows that a lack of understanding of metaphysics is an obstacle to understanding science. Metaphysical questions arise from our transcendence, that is, our ability to become subjects of our own knowledge: What is the conscious knowledge of humans compared to the sensitive knowledge of animals? What is a real being? What are mental beings (images, concepts, past, future, dreams)? What is the truth? What is causality? What is free will? What does it mean to understand something? Is the universe intelligible?
Basically, the answer to all of the above questions is that there is no answer. they are mysteries. We can understand what a human being is because we know everything we do and everything that happens to us, but we cannot define or explain what a human being is. In other words, humans are incarnated spirits. Using the categories of metaphysics, the human soul is spiritual. Assuming or hoping that the universe is intelligible leads to the existence of a transcendent reality that in Western religions is called God. God is not a free image, like Santa Claus, but a real being, like a beloved friend who gets on your nerves from time to time.
In science, there are no mysteries because science has a tremendous track record of success. There are only unanswered questions. It can be said of metaphysics that there is no record of success. An example of metaphysical wisdom is that knowledge is the opening of being to the self-manifestation of being. In metaphysics, whether or not the universe is intelligible is an open question. But in science, it is not. If Johannes Kepler thought for a minute that the universe wasn’t intelligible, he wouldn’t have spent 10 years trying to understand why the planets move the way they do. What caused the Big Bang is not a mystery. What consciousness is is a mystery. Calling both questions mysteries indicates that you don’t understand the difference between metaphysics and science.
A quantum puzzle arises from the question why the isotope cobalt-60 decays into nickel-60 with a half-life of 5.27 years. Using the probability waves of quantum mechanics, physicists can calculate the half-life of isotopes. A particular atom of cobalt-60 can decay in 10 minutes or 10 years. There is a 50% chance that it will decay in 5.27 years. This raises the question: What causes a particular cobalt-60 atom to decay at the particular time it does? With our current state of knowledge, there is no hope of answering this question. This is a riddle or puzzle because we understand a lot about quantum mechanical isotopes, but this is not.
The authors agree with the nonsense that there is a connection between human rationality (consciousness and free will) and quantum mechanics. I think this idea stems from a lack of understanding of the difference between science, metaphysics, and philosophy. Philosophy is a method of investigation that arises above another method of investigation. How scientists should do science is a philosophical question. The scientific method is an answer to this question. The various interpretations of quantum mechanics are part of the philosophy of quantum mechanics because they are attempts to answer questions about quantum mechanics.
One way to gain knowledge and understanding is through analogies. If you poke a lion in a cage with a stick, it will roar and try to scratch you. We know by analogy that the lion is angry because that’s how we would feel if it were happening to us. There is an analogy that is used in quantum mechanics to answer the question: What are quantum mechanical waves?
To answer this philosophical question, consider the breakdown of cobalt-60. If you observe a cobalt-60 atom for 5.27 years, it can decay (D) or remain stable (S). Repeated observations will give you a set of S and D. You get, in other words, a set: (S,S,D,D,D,S,..). The fraction of times you get S or D approaches half the limit as the number of elements in the set increases. I’m using set theory because you need set theory to understand an observation analogous to the cobalt-60 decay: tossing a coin into the air between your thumb and forefinger and getting heads (H) or tails (T). With coin tosses you get the same kind of set that you get when looking at cobalt-60 atoms. The probability of getting heads or tails is 1/2 because that is the fraction you get from the set and all possible subsets. In the case of the coin, there are two events (tossing and falling heads or tails), the subtle condition that the calculation be done for all subsets to eliminate the possibility of a daemon or hidden variable affecting the result, and the fact that we understand why it comes up heads (or tails) half the time. In the case of cobalt-60, there is only one event: the decay of the atom. These are two different phenomena. Saying “1/2 is the probability that a cobalt-60 atom will decay in 5.27 years” is either an analogy or a philosophical comment. In my opinion, calling the waves of quantum mechanics waves of probability is an example of philosophizing.
The basis for thinking that there is a connection between consciousness and quantum mechanics is the double-slit experiment with particles (photons, electrons, or atoms). A version of this experiment is found on YouTube.com (“Double Slit Experiment: Water Wave Interference Pattern”). The double slit creates two water waves and a highly visible interference pattern. The same interference pattern occurs with particles. The probability waves of quantum mechanics explain this and it is another triumph of quantum mechanics.
The big difference between the two interference patterns is that you don’t need a screen to see the interference pattern of the water. You do not see any particle interference pattern if there is no screen. But, the screen is there because a human being put it there. Therefore, it is the action of humans that created the interference pattern. This is a puzzle because it raises the question: What happens to the particles after they hit the double slit if there is no screen? In any case, this is the reasoning, as far as I can make out, behind the idea that quantum mechanics involves human consciousness but classical physics does not.