Einstein assumed reality was localized and definite in one of his famous 1905 papers, and physics never recovered from that ridiculous, out-of-the-blue, wanton, gratuitous error. (The present essay complements the preceding one found in the link).
At the origin of Quantum Mechanics is Max Planck’s train of thought. Max demonstrated that supposing that electromagnetic energy was EMITTED as packets of energy hf explained the two obvious problems of physics; h is a constant (since then named after Planck), f is the frequency of the light.
Then came, five years later, Einstein. He explained the photoelectric effect’s mysterious features by reciprocating Planck’s picture: light’s energy was RECEIVED as packets of energy hf. Fine.
However, so doing Einstein claimed that light, LIGHT IN TRANSIT, was made of “LICHT QUANTEN” (quanta of light), which he described as localized. He had absolutely no proof of that. Centuries of observation stood against it. And the photoelectric effect did not necessitate this grainy feature in flight, so did not justify it.
Thus Einstein introduced the assumption that the ultimate description of nature was that of grains of mass-energy. That was, in a way, nothing new, but the old hypothesis of the Ancient Greeks, the atomic theory. So one could call this the Greco-Einstein hypothesis. The following experiment, conducted in 1921, demonstrated Einstein was wrong. Thus the perpetrator Walther Gerlach, did not get the Nobel, and the Nobel Committee never mentioned the importance of the experiment. Arguably, Gerlach’s experiment was more important than any work of Einstein, thus deserved punishment The Jewish Stern, an assistant of Einstein, got the Nobel alone in 1944, when Sweden was anxious to make friends with the winning “United Nations”:
Yet, Einstein’s advocacy of nature as made of grains was obviously wrong: since the seventeenth century, it was known that there were wave effects ruling matter (diffraction, refraction, Newton’s rings). That was so true, Huyghens proposed light was made of waves. Around 1800 CE Young and Ampere proposed proofs of wave nature (2 slit experiment and Poisson’s dot). The final proof of the wave theory was Maxwell’s completion and synthesis of electromagnetism which showed light was an electromagnetic wave (travelling at always the same speed, c).
Einstein’s hypothesis of light as made of grain is fundamentally incompatible with the wave theory. The wave theory was invented precisely to explain DELOCALIZATION. A grain’s definition is the exact opposite.
There is worse.
Spin was discovered as an experimental fact in the 1920s. Interestingly it had been discovered mathematically by the French Alpine mathematician Elie Cartan before World War One, and stumbled upon by Dirac’s invention of the eponymous equation.
The simplest case is the spin of an electron. What is it? When an electron is put in a magnetic field M, it deviates either along the direction of M (call it M!) or the opposite direction (-M). This sounds innocuous enough, until one realizes that it is the OBSERVER who selects the direction “M” of M. Also there are two angles of deviation only. (The Gerlach experiment was realized with silver (Ag) atoms, but the deviation was caused by a single electron therein.)
Einstein would have us believe that the electron is a grain. Call it G. Then G would have itself its own spin. A rotating charged particle G generates a magnetic field. Call it m. If Einstein were correct, as the direction of M varies, its interaction between the grain G magnetic field m will vary. But it’s not the case: it is as if m did not count. At all. Does not count, at all, whatsoever. It’s all about M, the direction of M.
So Einstein was wrong: there is no grain G with an independent existence, an independent magnetic filed m.
Bohr was right: Einstein was, obviously, wrong. That does not mean that Bohr and his followers, who proclaimed the “Copenhagen Interpretation” were right on other issues. Just like Einstein hypothesized something he did not need, so did the Copenhagists.
Backtrack above: M is determined by the observer, I said (so bleated the Copenhagen herd). However, although M can changed by an observer, clearly an observer is NOT necessary to create a magnetic field M and its direction.
Overlooking that blatant fact, that not all magnetic fields are created by observers, is the source of Copenhagen confusion.
We saw above that correct philosophical analysis is crucial to physics. Computations are also crucial, but less so: a correct computation giving correct results can be made from false hypotheses (the paradigm here is epicycle theory: false axiomatics, the Sun did not turn around the Earth, yet, roughly correct computations produced what was observed).
Out of Quantum Theory came Quantum ElectroDynamics (QED), and, from there, Quantum Field Theory (QFT).
QED is one of the most precise scientific theory ever. However, there is much more precise: the mass of the photon is determined to be no more than 10^(-60) kilogram (by looking at whether the electromagnetic field of Jupiter decreases in 1/d^2…).
Nevertheless, QED is also clearly the most erroneous physical theory ever (by an order of 10^60). Indeed, it predicts, or rather uses, the obviously false hypothesis that there is some finite energy at each point of space. Ironically enough, it is Einstein and Stern (see above) who introduced the notion of “zero point energy” (so, when Einstein later could not understand, or refused to understand, Quantum Electrodynamics, it was not because all the weirdest concepts therein were not of his own making…)
The debate on the Foundations of Quantum Physics is strong among experts, all over the map, and permeated with philosophy. Thus don’t listen to those who scoff about whether philosophy is not the master of science: it always has been, it is frantically so, and always will be. It is a question of method: the philosophical method uses anything to construct a logic. The scientific method can be used only when one knows roughly what one is talking about. Otherwise, as in Zeroth Century, or Twentieth Century physics, one can go on imaginary wild goose chases.
From my point of view, Dark Matter itself is a consequence of the True Quantum Physics. This means that experiments could be devised to test it. The belief that some scientific theory is likely incites beholders to make experiments to test it. Absent the belief, there would be no will, hence no financing. Testing for gravitational waves was long viewed as a wild goose chase. However, the Federal government of the USA invested more than one billion dollars in the experimental field of gravitational wave detection, half a century after an early pioneer (who was made fun of). It worked, in the end, splendidly: several Black Hole (-like) events were detected, and their nature was unexpected, bringing new fundamental questions.
Some will say that all this thinking, at the edges of physics and philosophy is irrelevant to their lives, now. Maybe they cannot understand the following. Society can ether put its resources in making the rich richer, more powerful and domineering. Or society can pursue higher pursuits, such as understanding more complex issues. If nothing else, the higher technology involved will bring new technology which nothing else will bring (the Internet was developed by CERN physicists).
Moreover, such results change the nature not just of what we believe reality to be, but also of the logic we have developed to analyze it. Even if interest in all the rest faded away, the newly found diamonds of more sophisticated, revolutionary logics would not fade away.