These are the key mathematical ideas to understand!!
There are actually a few formulations out there. By far the dominant one as of 2020 has been the Schrödinger picture, which contrasts notably with the Heisenberg picture.
Another well known one is the de Broglie-Bohm theory, which is deterministic, but non-local.
There's about 60 of them.
Not a telephone-based system, needing its own network, and was killed particularly by fax which is. Telex evolved from the Telegraph, which is a binary system at the physical layer.
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