Is Cause and Effect Real? (Part 2)

As I finished reading my first book on the history and development of Quantum Mechanics, (Quantum: Einstein, Bohr, and the Great Debate About the Nature of Reality by Manjit Kumar), I recalled an article by Karen Harding, which I read prior to reading this book, that supposedly outlined the similarities between Ashari Atomism and the modern Atomic Theory (Quantum Mechanics). The article highlighted how Ghazali's Occasionalism had shocking similarities to Quantum Mechanics, specifically the Copenhagen Interpretation. I will share my thoughts on the similarities between Quantum Mechanics (Copenhagen Interpretation) and Ghazali's Occasionalism in Part 3 of this series. In this post however, I will try to summarize, with my limited knowledge, what Quantum Mechanics is and what the Copenhagen interpretation entailed. 

Just as I presented the conception of pure determinism and free by Al-Ghazali and Ibn Rushd respectively, in this post, pure determinism will be represented by Albert Einstein and free will by Niels Bohr.

It was Max Planck, a conservative theorist, who unintentionally discovered the world of the Quantum while he was trying to solve the problem of radiation emitted by a blackbody. The Ultraviolet Catastrophe, as it was being referred to, was the problem that was a result of the classical mechanics not matching with real life experiments. What classical mechanics was predicting was that if we keep on heating a blackbody radiator, it starts to emit a lot of UV light and even gamma rays. In real life experiments however, the UV light starts to fall and not infinitely increase as classical mechanics predicted. (Thank God this was the case, we wouldn't exist if classical mechanics was correct). 

What Planck did, as an act of desperation, he recalled later, was that he came up with an equation that aligned the classical mechanics with real life experiments, which resulted in the two lines (graph) to align. Although he "solved" the problem, Planck had no physical description or explanation as to how and why his equation solved the blackbody problem. What Planck did with his equation was that he quantized the energy of an atom as opposed to letting it be continuous. What that meant was that he allocated certain values to the energy of the atom and prevented the atom from having any energy level. The energy of an atom can only be a whole number (1,2,3,...) and not (1.1,1.123,...). This won Planck a Nobel Prize but he was still not able to provide a physical explanation for his "desperate" equation that he happened to come up with. This honor would go to Albert Einstein. To sum it up, Einstein's explanation was that light (photon) itself was quantized and not a wave of probabilities at least for the explanation of his photoelectric equation. Einstein won the Nobel Prize for his photoelectric law but his explanation that light itself was quantized was too hard for physicists to accept. Planck himself, despite the evidence, believed that when energy was being transferred only then did it act like particles not that light itself was quantized. Einstein went on to discover his theory of  Relativity and had become world famous but one thing still troubled him: How could light quanta (photon) exhibit both particle and wave like behavior simultaneously? Einstein said towards the end of his life, "All these 50 years of conscious brooding have brought me no near to the question - what are light quanta?"

Niels Bohr, the 'Golden Dane' , a Danish physicist, began working on the atom and as he progressed, he would tell his brother that he wanted to fix Rutherford's "flawed" nuclear atom by turning it into the 'Quantum atom'. With Bohr we saw great courage as he courageously moved away from concepts established in classical physics such as placing restriction on an electron's orbit inside an atom by  'quantizing' electron orbits. Bohr also abandoned the accepted notion that an electron could orbit an atomic nucleus at any given distance. An electron, he argued, could occupy only a few select orbits, the 'stationary states'. Although Bohr was making these discoveries, his models were flawed and failed to answer many questions. He started to posit ideas that were too erroneous for physicists to accept. Such as electron jumps and the impossibility to say where an electron is during a jump from a lower energy level to a higher energy level and vice versa. As if by magic, an electron disappeared while in one orbit and reappeared in another. This is where 'chance' or probability came into action with no connection between cause and effect. Einstein was uneasy with the discovery of chance and probability as causality appeared to be at risk because the transition of an electron from an energy level to another, left the time and direction down to pure chance. To simplify this concept of transition, this analogy would be useful:

An apple being held above the ground, that when let go did not fall. Once the apple is let go, it is in an unstable state with respect to the state of lying on the ground, so gravity acts immediately on the apple, causing it to fall. If the apple behaved like an electron, then instead of falling back as soon as it was let go, it would hover above the ground, falling at some unpredictable time that can be calculated in terms of probabilities. There may be a high probability that the apple will fall within a very short time, but there is a small probability that the apple will hover above the ground for hours.

Einstein famously said, "I find the idea quite intolerable that an electron should choose of "it's own free will", not only it's moment to jump off, but also it's direction."

Another interesting point of divergence between Einstein and Bohr was the interpretation of the double-slit experiment conducted in the mid-1920's.

Even if electrons were fired one at a time, the result was an interference pattern which is associated with waves. How could electrons, points of energy (particles), behave like waves? Einstein and Niels Bohr both had different interpretations. One of Neil Bohr's colleagues, Werner Heisenberg, discovered the 'Uncertainty Principle' to explain this phenomenon. Niels Bohr was the foremost advocate of his principle and made changes to improve it until he claimed that quantum mechanics was now, because of the uncertainty principle, a complete description of reality. Einstein being the voice of reason denied this claim and interpreted this phenomenon differently. By the joint efforts of Wolfgang Pauli, Werner Heisenberg, Niels Bohr and others at Copenhagen, the theory was termed ‘The Copenhagen Interpretation’.

The Copenhagen Interpretation suggested that we can not describe what is travelling as a physical object, all we can talk about are the chances of where the electron might be. This wave of chance somehow travels through both slits and produces an interference just like a water wave. Then when it hits the screen, what was just the possibility of an electron mysteriously becomes real. To explain this absurdity with an analogy, if I spin a coin it is "both heads and tails" until I stop it and "summon" either heads or tails into existence. All of this defied common sense and was so counter-intuitive. Whereas the electron jumps questioned causality, the Copenhagen Interpretation of the double-slit experiment suggested that there was no objective reality and it is only upon observation that reality is "summoned" into existence. Strangely enough, somehow Quantum Mechanics suggested that when you are not looking at the moon it does not exist.  

On one hand causality was being questioned and on the other an observer-independent reality was challenged. Einstein, as adamant as he was, could not digest the denial of an objective reality and if he were to choose between giving up causality or an objective reality, he would give up causality because for him denying objective existence was too much a price to pay. Both the titans, Einstein and Bohr, clashed over the conception of nature that the Copenhagen Interpretation suggested. For Einstein the world of the Quantum was providing accurate results but it could not be a complete description of the physical world. Einstein could not accept the accepted notions of classical mechanics being neglected. Neils Bohr would once say on Einstein's conservatism, "It was Einstein's very successes that kept him anchored in the past."

Any interpretations that Einstein gave were proved wrong when John Stewart Bell derived his theorem and proved that Neils Bohr was right. The world of the Quantum did in fact run on probabilities and that causality did not operate in the world of the micro. Classical Mechanics could predict with the utmost accuracy the future trajectory or state of any object but Quantum Mechanics suggested that there was no absolute accuracy and that probabilities existed regarding the future state of any given object at the micro level.