Gerenuk said:According to QFT, how do two masses attract?
Is the action instantaneous? How is momentum/energy conserved? Is the action non-local?
Gerenuk said:According to QFT, how do two masses attract?
Yes, I did ask about gravity. But it would also be interesting to know how the Coulomb force acts through photons. At some point I will dive into QFT, but for know I was hoping to get a rough answer about what happens when two charges interaction. I mean where/when are there photons? How is momentum conserved?jtbell said:Since you said "masses", are you asking specifically about gravity? There is no generally accepted QFT for gravity yet, as far as I know, so this is still an open question.
Look at the Hamiltonian of QED. It has three terms, one for the electron, one for the EM field, and an interaction term that is like [itex]\mathbf{A} \cdot \mathbf{J}[/itex]. The virtual photons that exchange energy between the field and the matter live in the interaction term.Gerenuk said:... now I was hoping to get a rough answer about what happens when two charges interaction. I mean where/when are there photons? How is momentum conserved?
jtbell said:Since you said "masses", are you asking specifically about gravity? There is no generally accepted QFT for gravity yet, as far as I know, so this is still an open question.
Gerenuk said:Yes, I did ask about gravity. But it would also be interesting to know how the Coulomb force acts through photons. At some point I will dive into QFT, but for know I was hoping to get a rough answer about what happens when two charges interaction. I mean where/when are there photons? How is momentum conserved?
The QFT (Quantum Field Theory) picture of forces is a theoretical framework that explains the interactions between elementary particles and their corresponding force carriers. It is based on the concept of quantum fields, which describes the fundamental particles of matter as excitations in a field that permeates all of space.
The QFT picture of forces differs from classical physics in that it takes into account the principles of quantum mechanics, which describes the behavior of particles at the subatomic level. In classical physics, forces are described as acting at a distance, while in QFT, forces are mediated by particles exchanging energy and momentum.
The four fundamental forces in the QFT picture are the strong nuclear force, the weak nuclear force, electromagnetism, and gravity. Each of these forces is carried by a specific type of force carrier particle, such as gluons for the strong force and photons for electromagnetism.
The QFT picture of forces explains the unification of forces by showing how the four fundamental forces can be described by a single theoretical framework. This is achieved through the concept of symmetry breaking, where at high energies, all four forces are thought to be unified into a single force, but as the energy decreases, the forces become distinct and separate.
The QFT picture of forces is significant in understanding the universe because it provides a comprehensive framework for describing the interactions between all particles and forces. It has been successful in predicting and explaining many phenomena, such as the behavior of subatomic particles and the origin of the universe. It also allows for the exploration of new theories and potential unification of forces, which could lead to a deeper understanding of the fundamental nature of our universe.