# Particle Physics vs Quantum Field Theory vs Standard Model

FourEyedRaven
Hi.

I'd like to ask what are the differences between Particle Physics, Quantum Field Theory and the Standard Model. I see these names of physics courses but I want to confirm if I understand the difference.

My understanding is that when students learn particle physics in their undergraduate years they are learning how particles interact without knowing the background theoretical structure that justifies the calculations they learn. Quantum field theory is the general theoretical framework of quantized fields. The standard model is the specific model of quantized fields that describes how three of the four fundamental forces are unified. So the standard model contains the background theoretical structure that justifies the calculations that students learn in particle physics courses.

Is this correct? Sort of?

Gold Member
Basically.

Particle physics is the study of particles, their properties and how they interact. There are a couple of ways you can model particles, but the most general theory for doing so is Quantum Field Theory, which is used when the quantum nature of particle must be taken into account and they are moving at relativistic speeds. This theory describes particles as a special type of state of the underlying quantum fields.

Quantum Field Theory is a very general framework and a given quantum field theory can have several fields of various spins with a variety of interactions. The standard model is the particular quantum field theory that seems to correctly model the particle's we can observe and the three forces that govern them. However note it does not unify those forces.

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• FourEyedRaven
FourEyedRaven
Right. So is it fair to say that it's somewhat similar to the differences between classical thermodynamics, statistical physics, and statistical thermodynamics?

Staff Emeritus
Right. So is it fair to say that it's somewhat similar to the differences between classical thermodynamics, statistical physics, and statistical thermodynamics?

Actually, no.

QFT is really QM, but in a different light. Some might even say QFT is really QM in Second Quantization formalism.

Particle physics (of which the standard model is a part of) is a field of physics that makes use of QM/QFT. But it isn't the only one. Condensed Matter Physics, Nuclear Physics, Atomic Physics, etc... all make use of QFT.

Zz.

• FourEyedRaven