Cindynics, The Science of Danger

Appendix 4Notions of Quantum Theory

The break with classical theories

The quantum theories born at the beginning of the 20th century marked a complete break with the physical principles accepted in the 19th century (Newtonian and electromagnetic theories). Through the study of “microsystem states”, these new theories came to describe the structure of atoms and molecules and explain that matter is not only composed of visible elements but also has many invisible aspects. They have thus constituted a “conceptual change. For the first time, both pure reason and what is believed to be ‘common sense’ are being challenged by experimental facts. We must build a new way of thinking about reality, a new logic” [BAS 02].

Do our senses perceive reality?

Previously, knowing an object was being able to say what it is. To recognize a certain table, for example, was to be able to describe it in shape and appearance (length, width, height, constituent materials, color). The knowledge consisted of a description of an object, that is, a translation transmissible by a language of reality as it was approached. “All our language, all logic and classical probabilistic thinking are based on this postulate, more or less implicitly” [MUG 77].

Now, quantum theory shatters this conception of knowledge acquisition, for it shows that the world of the infinitely small behaves very differently from our macroscopic universe. Every observer influences the state of the microscopic system observed with their ...