Quantum Theory
The quantum theory of the atom was developed to explain a phenomenon in the natural world, where sub-atomic particles called electrons normally remain in a wave–particle-wave function orbital path around/through the nucleus of an atom.
This phenomenon could not be explained by classical mechanics laws, such as Newton’s laws of motion and some of Maxwell’s laws of classical electromagnetism.
An electron orbiting an atom’s nucleus has quantized values of energy and angular momentum. An unbound electron does not show quantized energy levels, but is associated with a Compton wavelength, as are all particles.
This wave-function is a complex mathematical function of time and space (vector space) that can provide information about the position and momentum of a particle in an actual experiment, but only as a probability within the rules of the uncertainty principle.
Many of the results of Quantum Mechanics can only be expressed mathematically. There are no models that are as easy to visualize as those of classical mechanics.
The chief problem is reconciling the many possibilities for a quantum particle’s state, encoded in its wave function, with the fact that we can observe only one at the time.
The Born rule calculates the probability that a measurement of a quantum system or state will yield a given result: the square of the amplitude at the moment of observation, its entanglement:
US physicist Hugh Everett’s interpretation made in 1957 is, that all those possibilities encoded in Schrödinger‘s wave function are actualities that play out in parallel realities.
We observe, perceive, become entangled, and interact, with only one possibility because we are confined to one reality, meaning one branch of this wave function:
That wave function, with all its parallel strands as multiple-worlds, is the multiverse, the ultimate reality. One quantum object in a superposition is just one strand.
Another interpretation in which the wave function is real is the “collapse interpretation”. Here, the wave function contains all possibilities until we send attention energy to one event inherent to the wave function, while the other possibilities seem to have disappeared, but in reality they just fail to interact with the other branches.
Environmental decoherence is the cause.
The Double-Slit experiment
