28 feb. 2017
sayanyein Both-particle-and-wave viewNeither-wave-nor-particle view
Wave–particle duality is the concept that every
elementary particle or
quantic entity may be partly described in terms not only of
particles, but also of
waves.
It expresses the inability of the
classical concepts "particle" or "wave" to fully describe the behavior of
quantum-scale objects.
As
Albert Einstein wrote: "
It
seems as though we must use sometimes the one theory and sometimes the
other, while at times we may use either.
We are faced with a new kind of
difficulty.
We have two contradictory pictures of reality; separately
neither of them fully explains the phenomena of light, but together they
do."
[1]
Through the work of
Max Planck, Einstein,
Louis de Broglie,
Arthur Compton,
Niels Bohr and many others, current scientific theory holds that all particles also have a wave nature (and vice versa).
[2]
This phenomenon has been verified not only for elementary particles,
but also for compound particles like atoms and even molecules.
For
macroscopic particles, because of their extremely short wavelengths, wave properties usually cannot be detected.
[3]
Although the use of the wave-particle duality has worked well in physics, the
meaning or
interpretation has not been satisfactorily resolved;
see
Interpretations of quantum mechanics.
Niels Bohr regarded the "duality
paradox"
as a fundamental or metaphysical fact of nature.
A given kind of
quantum object will exhibit sometimes wave, sometimes particle,
character, in respectively different physical settings.
He saw such
duality as one aspect of the concept of
complementarity.
[4]
Bohr regarded renunciation of the cause-effect relation, or
complementarity, of the space-time picture, as essential to the quantum
mechanical account.
[5]
Werner Heisenberg
considered the question further.
He saw the duality as present for all
quantic entities, but not quite in the usual quantum mechanical account
considered by Bohr.
He saw it in what is called
second quantization,
which generates an entirely new concept of fields which exist in
ordinary space-time, causality still being visualizable.
Classical field
values (e.g. the electric and magnetic field strengths of
Maxwell) are replaced by an entirely new kind of field value, as considered in
quantum field theory.
Turning the reasoning around, ordinary quantum mechanics can be deduced as a specialized consequence of quantum field theory.
[6][7]