What's the difference between QFT and Atomic physics

In summary, atomic physics is the study of atomic interactions and behavior, nuclear physics is the study of nuclear interactions, and high energy/particle physics is the study of fundamental particle interactions. These fields are all based on quantum mechanics, but in order to study interactions involving light and matter, a relativistic version called quantum field theory is necessary. QED, QCD, and other theories are based on QFT and are used to describe different forces and interactions. These fields all overlap and build upon each other to form a comprehensive understanding of the physical world.
  • #1
robertjford80
388
0
For physics between QM and String Theory I've heard a lot of different names.

Quantum Electrodynamics seems to be the physics of the electron and the photon.

Quantum Chromodynamics seems to be the physics of quarks.

But High Energy/Nuclear/Particle Physics, Atomic physics, QFT, I don't know what the difference between them is. This forum has one category for HE/N/P physics and another for atomic physics so there has to be some difference.
 
Physics news on Phys.org
  • #2
Atomic physics - study of atomic interactions
Nuclear physics - study of nuclear interactions
High energy/particle physics - study of fundamental particle interactions
QFT - the underlying mathematical theory of particle interactions, the particle world version of Newtons laws of motion. You take QFT and put various sorts of particles into it to create QED, QCD etc.
 
  • #3
Atomic physics is the application of quantum mechanics to the atom, to study, as kurros says, atomic interactions and behavior.

In order to study the interactions of light and matter (QED), we need a relativistic version of quantum mechanics -- this is quantum field theory. So QED and QCD are physical theories based on QFT.

High energy physics is basically synonymous with particle physics, which is the study of the elementary particles and forces of nature. Modern particle physics is based on the Standard Model, which encompasses QED, QCD, and the theory describing the electroweak force.

So, really you have:

Atomic physics <----- Quantum mechanics
Particle physics (high energy physics) <------- QED, QCD, others <------- QFT
Nuclear physics <------- QCD, others <------- QFT, others
 
  • #4
bapowell said:
So, really you have:

Atomic physics <----- Quantum mechanics
Particle physics (high energy physics) <------- QED, QCD, others <------- QFT
Nuclear physics <------- QCD, others <------- QFT, others

To be more precise, QFT is required to do precision atomic physics (the most obvious and historically first example is the Lamb shift calculation). Quantum mechanics as taught in undergraduate physics classes is not sufficient to do precision atomic physics (for example second order perturbation theory of most interactions gives infinite results).
 

Related to What's the difference between QFT and Atomic physics

1. What is QFT and how is it different from Atomic physics?

QFT stands for Quantum Field Theory and it is a theoretical framework that combines quantum mechanics and special relativity to describe the behavior of particles on a subatomic level. Atomic physics, on the other hand, deals with the study of atoms and their constituents, such as electrons, protons, and neutrons. The main difference between QFT and Atomic physics is that QFT is a more general theory that applies to all particles, while Atomic physics focuses specifically on the behavior of atoms.

2. How does QFT explain the behavior of particles?

QFT explains the behavior of particles by treating them as excitations of underlying quantum fields. These fields are present throughout space and time and their interactions create the particles that we observe. QFT also takes into account the principles of uncertainty and relativity, which help to explain the probabilistic nature of particle behavior and the speed at which they move.

3. What are some real-world applications of QFT and Atomic physics?

QFT and Atomic physics have many real-world applications, such as in the development of new technologies, understanding the behavior of materials, and in the field of nuclear energy. For example, QFT is used in the development of quantum computers and Atomic physics is essential in the study of nuclear reactions and power generation.

4. Can QFT and Atomic physics be applied to the same systems or phenomena?

Yes, QFT and Atomic physics can be applied to the same systems or phenomena, but they may provide different levels of understanding. For example, both theories can be used to study the behavior of electrons in atoms, but QFT provides a more complete and accurate description of their behavior due to its incorporation of quantum mechanics and relativity.

5. Is QFT a more advanced theory than Atomic physics?

QFT can be considered a more advanced theory than Atomic physics because it encompasses and builds upon the principles of Atomic physics. QFT also allows for a deeper understanding of the fundamental nature of particles and their interactions, whereas Atomic physics focuses on the behavior of specific systems, such as atoms. However, both theories are important and have their own unique applications in the scientific world.

Similar threads

A Why KE of Annihilation Electrons Differs?
    • High Energy, Nuclear, Particle Physics
Replies
11
Views
1K
A What knowledge is needed to understand modern QFT research?
    • High Energy, Nuclear, Particle Physics
Replies
25
Views
2K
Quantum Math Textbooks to Read Before Starting QFT
    • Science and Math Textbooks
Replies
9
Views
692
A Lehmann Kallen and spectral representation
    • High Energy, Nuclear, Particle Physics
Replies
1
Views
2K
B Frequency of an EM wave in Classical and Quantum Physics
    • Quantum Physics
Replies
6
Views
914
I Do atoms recoil when emitting a photon?
    • Quantum Physics
2
Replies
38
Views
3K
A What determines particle size in an atomizing spray nozzle?
    • High Energy, Nuclear, Particle Physics
Replies
3
Views
2K
A Ensembles in quantum field theory
    • Quantum Interpretations and Foundations
3
Replies
91
Views
6K
I Particle Physics vs Quantum Field Theory vs Standard Model
    • High Energy, Nuclear, Particle Physics
Replies
3
Views
17K
B Can alpha radiation make other materials radioactive?
    • High Energy, Nuclear, Particle Physics
Replies
6
Views
2K

Hot Threads

Recent Insights

Back
Top