Caption: A highly simplified schematic diagram showing the relationships of 4 important branches of physics.

From one perspective, you can view the quantum mechanics, general relativity (AKA relativistic mechanics), and classical mechanics (AKA Newtonian physics) as approximations to quantum field theory---which does NOT yet include the theory of everything (TOE) which remains unknown.

From another perspective, you can view these branch theories as emergent theories which are exactly true in certain limits. For example, classical mechanics can be viewed as exactly true in the classical limit.

Both perspectives are useful, but yours truly has come believe that emergence is the most fruitful for the advancement of science and general understanding of physics and reality in general.

Credit/Permission: © User:YassineMrabet, 2008 / Creative Commons CC BY-SA 3.0.
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