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Video link Quantum Mechanics an artist view.
But people say time has nothing to do with quantum mechanics and that time is linked to the laws of thermodynamics. It is true that almost all phenomena that behave differently in one time direction can ultimately be linked to the Second Law of Thermodynamics.
This is because of a spontaneous natural process of energy becoming dispersed or spread out (more disorder) if not hindered from doing so. The measurement of this change in temperature is called Entropy.
The Second Law of Thermodynamics says the entropy of an isolated system will increase when no extra energy is consumed. Entropy is almost the only quantity in the physical sciences that "picks" a particular direction for time, sometimes called an arrow of time.
But the Second Law also says that locally entropy of an isolated system in equilibrium will remain the same and there will be no arrow of time for the system. Also for living systems local entropy can decrease with time (become more organized). If time was a product of entropy time would be moving backwards within such a system.
The abstract nature of the spontaneous natural process that forms the second law needs a precise physical cause which the theorem is a consequence of.
The Second Law of Thermodynamics is statistical in nature, and therefore its reliability arises from the huge number of classical particles present in macroscopic systems.
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But at the microscopic level of individual atoms each part of the system is subject to Heisenberg’s Uncertainty Principle. Time is reversible in quantum mechanics a notable exception is the wave function collapse in quantum mechanics, which is an irreversible process! (Just like time).
In Quantum Atom Theory it is this spontaneous process of the wave function continuously radiating out a square of probability from its radius. That forms entropy and the spontaneous statistical nature of the Second Law of Thermodynamics.
We can also see that thermodynamics is formed by the wave function by looking at the Third Law of Thermodynamics. The Third Law of Thermodynamics says as a system approaches absolute zero of temperature all processes virtually cease and the entropy of the system approaches a minimum value. The entropy of all systems and of all states of a system would be smallest at absolute zero.
This is because if we could achieve absolute zero the quantum wave particle function would also virtually cease. There would be no Spontaneous process that Einstein called stimulated emission for entropy to take place.