Classical mechanics works well, except to compute the energies of small sets of particles. On the contrary, the PRINCIPLES of quantum mechanics lead to absurdities (the paradoxes), or numerical errors ( the spontaneous emission is twice larger than the result of quantum mechanics; it is impossible to define a wave function for the photon...).
Quantum mechanics says that it solves the wave particle duality leaving the physicist choose arbitrarily what he likes (or remain in the vague, the users of quantum electrodynamics using optical modes which are not defined).
The solitons solve this problem, giving a mathematical support to the "double solution". of de Broglie.
The FORMALISM of quantum mechanism works well, but it may be considered as a phenomenology, valuable as well in a classical scheme than using the absurd principles of QM.
At the beginning, de Broglie and Schrödinger introduced waves to compute the energies, but it is equivalent and much easier to use Lie algebra; the spin becomes a mathematical concept which is not easily physically explanable.

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JMB