[Physics] Is this summary of modern theoretical physics correct

particle-physicsquantum-field-theorystandard-model

This is not exactly a physics question; it's more of a question about physics. You'll see what I mean in a minute. My understanding of modern theoretical physics is below. What I want to know is: Is my summary correct? Am I understanding all of this correctly? Or is there something wrong or missing in the synopsis? Here it is:

  • Standard Model–Explains every force except gravity and the fundamental particles. It's made of 3 parts:
    • Quantum Chromodynamics (QCD)–A quantum field theory (QFT) that explains the strong force through quantum mechanics (QM).
    • Electroweak Theory (EWT)–A QFT that explains the electromagnetic and the weak force through QM.
      – Quantum Electrodynamics (QED)–A QFT that explains the electromagnetic force through QM.
      – Quantum Flavordynamics (QFD)–A QFT that explains the weak force through QM, though the term QFD is rarely used.
      – Higgs Mechanism–Explains how particles get their masses.

      • Einstein's Theory of General Relativity–Explains gravity.

A quantum field theory is a theory that explains some aspect of physics as a field and unties quantum mechanics and special relativity to do so. The four quantum field theories (QCD, QED, QFD, and EWT) unite quantum mechanics and special relativity. They are all fully understood, complete, and proven. The Higgs mechanism, which works through the Higgs field (which is made up of Higgs bosons), has been verified when the Higgs Boson was discovered. It is therefore also understood, complete, and proven. The four QFT's , along with the Higgs mechanism, make up the Standard Model. The Standard Model does not attempt to explain the fourth force, gravity. This is left to Einstein's Theory of General Relativity (GR).

A Grand Unified Theory (GUT) would combine QED and EWT. Quantum Gravity (QG) would unite QM and GR. A Theory of Everything (TOE) would unite QG and GUT. Loop Quantum Gravity is a proposed QG, but has not been proven. String Theory is a proposed TOE but has not been proven.

So, is any/all of this incorrect? Thanks in advance.

Best Answer

The four quantum field theories (QCD, QED, QFD, and EWT) unite quantum mechanics and special relativity. They are all fully understood, complete, and proven.

In your quote for the standard model, there are not four distinct field theories, the electroweak has united the electromagnetic and the weak in one field theory, the electroweak theory. The standard model unites the strong QCD field theory all in one field theoretical formulation with the electroweak, three forces, electromagnetic, weak and strong. Ideally these forces at some high energies are unified into one force, and that is the aim of the GUT .

A Grand Unified Theory (GUT) would combine QED and EWT.

Quantum Gravity (QG) would unite QM and GR.

Quantum gravity is the quantization of gravity. Unite is not a good verb.

A Theory of Everything (TOE) would unite QG and GUT.

unify, not unite . otherwise OK

Loop Quantum Gravity is a proposed QG, but has not been proven*.

and has problems with special relativity.

String Theory is a proposed TOE but has not been proven*.

*correct, though proven is a bad verb for a physics model. Validated is the correct term. Physics models are accepted if validated by all known data and falsified even by one disagreement with data, when the model has to go back to the drawing board.

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