QUANTUM METAPHYSICS - E-thesis

material. These experiments agreed with Young’s well-known double-slit experiments 456 , which
had revealed the wave-like nature of light. The interference phenomena observed corresponded
to De Broglie’s calculations predicting the wavelength values. The power of the testimony
provided by these experiments could not be denied, even though they could not be explained in
any way acceptable to classical mechanics. Physicists had to accept the situation and when
necessary, associate radiation with particle properties and particles with wave-like properties.
The need to develop a new mechanics able to respond to the problems that had been thrown up
and explain wave-particle dualism was clear. Fortunately, an extensive quantity of spectroscopic
material which revealed the wavelengths at which different atoms radiated was available.
4.1.2. The development of quantum theory
At this point it was verified by experiments that in certain situations waves had particle-like
features, whereas in others the objects that had traditionally been seen as particles had to be seen
through their wave-like features. Nonetheless, it remained unsolved how these different
phenomena could be understood and brought together: the waves spread out through the space,
whereas a particle can always be localized in a single point. Even though a clear visualisable
understanding of these phenomena has proved difficult, scientists had already come up with
several mathematical solutions in the 1920s.
In the summer of 1925, Werner Heisenberg introduced the first actual quantum theory, namely
matrix mechanics. He had discussed quantum problems with Bohr throughout the spring and had
come to the conclusion that in the study of these new phenomena, all concepts and
presuppositions that might lead the mind astray should be stripped away. Inspired by Positivist
ideals, Heisenberg eliminated from his theory all variables and mental images that were not
empirically verifiable. He did not therefore even attempt to describe how the atom was structured
or what happened inside it. By moving beyond the discussion concerning the orbits and quantum
jumps of electrons, Heisenberg was able to avoid the problems that classical physics confronted
with its use of mechanical images and space-time descriptions. 457
Heisenberg, who relied on mathematics, noticed that even if the traditional description of the
position of the electron as a function of time in space appeared impossible, it was instead
456 Young’s double-slit experiment will be further discussed in Section 4.2.2.
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