What Subfield of Physics has the *most* QM involved in it?

[ChrisisC]

i'm assuming is particle physics... but could it be anything else? I am curious to know because i am trying to lay out a path for my educational career and i definitely know physics is my path. However, i don't know exactly was field of physics i want to specialize in. I think QM is the most fascinating scientific topic and i want my entire career to incorporate it as much as possible. thanks!

 

[dextercioby]

i'm assuming is particle physics... but could it be anything else? I am curious to know because i am trying to lay out a path for my educational career and i definitely know physics is my path. However, i don't know exactly was field of physics i want to specialize in. I think QM is the most fascinating scientific topic and i want my entire career to incorporate it as much as possible. thanks!

Foundations of QM (still an open topic even after 90 years) has the most QM in it. (!) This is not a suggestion for choosing a path for your university and post university education.

 

[radium]

Quantum condensed matter would be up there.

 

[Dr. Courtney]

I always felt that atomic and molecular physics was the purest QM in that you know all the potentials to great accuracy and are applying straight QM. QM in cases where the potentials are not really known never made sense to me.

 

[TomServo]

Particle physics is all QFT, quantum field theory, the relativistic version of QM. Very different.

 

[Crass_Oscillator]

Back up, have you even taken QM yet? Are you an undergrad? High school student? Graduate student? Precocious hermit?

 

[Mmm_Pasta]

Particle physics is all QFT, quantum field theory, the relativistic version of QM. Very different.

QFT is not necessarily the relativistic version of QM. You can have non-relativistic quantum field theories. It's an extension of quantum mechanics to infinite degrees of freedom. Here's something to see some connections between QFT, classical field theory, and relativity:

https://plato.stanford.edu/entries/quantum-field-theory/

To the OP: in modern physics, most fields of research will incorporate quantum mechanics. Just as Crass Oscillator asked, what is your educational background?

 

[TomServo]

QFT is not necessarily the relativistic version of QM. You can have non-relativistic quantum field theories. It's an extension of quantum mechanics to infinite degrees of freedom. Here's something to see some connections between QFT, classical field theory, and relativity:

https://plato.stanford.edu/entries/quantum-field-theory/

To the OP: in modern physics, most fields of research will incorporate quantum mechanics. Just as Crass Oscillator asked, what is your educational background?

Yes, but in practice isn't QFT used relativistically? I'm just describing it as I've heard other, much more knowledgeable people describe QFT. I took a class in it and still don't understand any of it, clearly.

 

[Crass_Oscillator]

In condensed matter and nuclear physics, you can have field theories that are quantized but non-relativistic, I think, although I am not an expert.

 

[radium]

Condensed matter attempts to describe many body systems in terms of their "emergent" properties. That's what fermi liquid theory is. You take an interacting system of electrons (with some assumptions) and describe it in terms of quasiparticles which behave somewhat like free electrons except they have a renormalized mass and charge and a finite lifetime.

These systems are in general nonrelativistic and space and time can scale differently (the different scaling is reflected in the dynamical critical exponent z which is 1 for Lorentz invariance, 2 for Galilean invariance). Sometimes even different spatial directions can scale differently. You can have emergent Lorentz symmetry which happens a lot at quantum critical points.