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Comment by echopurity | Hacker News Reader

How about just physics? "Newtonian physics" is a fake and outdated attribution anyway.

Or 'Classical Mechanics' as most university courses refer to it. Newtonian mechanics is an outdated name for simplified mechanics that approximate accurately for "normal" physics situations, at least normal for a human's daily life at this point in time.

The opposite end of this spectrum is Relativistic Mechanics, which takes over when the approximations fall away at realms deviating far from normal, such as high mass systems, those at speeds approaching C, or Quantum Mechanics for small scale like atomic interactions.

Classical mechanics wraps up general relativity, Newtonian mechanics, and analytic mechanics (which itself wraps up Hamiltonian mechanics and Lagrangian mechanics) into one name. It can also include fluid mechanics and other forms of continuum mechanics. Newtonian mechanics specifically refers to the formulation of finite-particle mechanics as a second order differential equation set in an inertial reference frame. Typical introductory physics classes teach Newtonian mechanics specifically.

Newtonian physics is a specific kind of physics distinct from other kinds which is why it has a sub-name.

Newton only contributed the three laws of motion to the model. https://en.wikipedia.org/w/index.php?title=Newtonian_mechani... The model includes additions from Leibnitz, Euler, Lagrange, and others from around the same time. The name "classical mechanics" doesn't pretend that Newton came up with all that stuff.

Classical mechanics includes everything that's not quantum, including general relativity and the Navier-Stokes equation. It is not a suitable term for Newtonian mechanics because it already refers to a much larger category.

According to https://en.wikipedia.org/wiki/Classical_mechanics#History, that's a recent change. It didn't used to include special or general relativity.

Well obviously it couldn't include general relativity before it was discovered. :-)

Newtonian refers to a particular model of physics. There's also Ptolematic model, the GR model and many others. But Newtonian is the most popular.

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