Although quantum mechanics has been very successful, we must remember that quantum mechanics only describes and predicts observable physical phenomena; it does not describe the inner reality of physical matter. In fact, as quantum mechanics advanced, different and conflicting interpretations of quantum mechanics developed, even among eminent physicists.
One of the earliest interpretations of quantum mechanics is the Copenhagen interpretation, which was led by a Danish physicist, Dr. Niels Bohr. This interpretation states that “there is no deep reality,” and atoms, electrons, and photons do not exist like objects in our everyday experience. According to this interpretation, a phenomenon fully comes into existence only when it is observed. Bohr once described it this way: “There is no quantum world. There is only an abstract quantum description.”
However, inherent paradoxes were known to exist in logic. And a variety of paradoxes were also discovered in set theory, such as Russell’s paradox. Those paradoxes all have two things in common: self-reference and contradiction. A simple and well known paradox is the liar paradox such as “I always lie.” From such a statement it follows that if I am lying, then I am telling the truth; and if I am telling the truth, them I am lying. The statement can be neither true nor false. It simply does not make sense. From the discovery of paradoxes in set theory, mathematicians suspected that there may be serious imperfections in other branches of mathematics.