- #1
AleksanderPhy
- 43
- 0
Hello I am little bit confused about one topic on theoretical Physics and that is If we want to describe our Quantum world (example atoms in metal) then should I use Quantum field theory or Quantum mechanics?
Thanks for such great awnser!A. Neumaier said:If you want to have enough detail, you need quantum field theory, but in many cases, quantum mechanics is sufficient. Metals can be described in both ways. Usually one begins with the particle description (quantum mechanics) and then switches to the field description (quantum field theory) as it is more powerful.
Quantum field theory (QFT) is a theoretical framework that combines quantum mechanics with special relativity to describe the interactions of subatomic particles. It is an extension of quantum mechanics, which deals with individual particles and their properties. QFT considers particles as excitations of underlying fields, and describes their behavior in terms of interactions between these fields.
In quantum mechanics, the behavior of a particle is described by a wave function, which is a solution to the Schrödinger equation. In quantum field theory, the behavior of particles is described by quantum fields, which are operators that act on the wave function. The equations of QFT are more complex, but they allow for the description of interactions between particles and the creation and annihilation of particles.
Both theories are necessary for a complete understanding of subatomic particles. Quantum mechanics is better suited for describing individual particles and their properties, while quantum field theory is better suited for describing interactions between particles and the creation and annihilation of particles.
No, QFT and quantum mechanics do not contradict each other. In fact, QFT is an extension of quantum mechanics and builds upon its principles. QFT provides a more comprehensive framework for understanding the behavior of particles, but it does not contradict the principles of quantum mechanics.
Quantum mechanics is used in a variety of applications, such as the development of new technologies like transistors and lasers. Quantum field theory is used in high-energy physics, particularly in the study of particle interactions and the behavior of subatomic particles. Both theories have been extensively tested and verified through experiments, and are essential for our understanding of the subatomic world.