What does the Feynman diagram show?
A Feynman diagram is a diagram that shows what happens when elementary particles collide. Feynman diagrams are used in quantum mechanics. In Feynman diagrams, the particles are allowed to go both forward and backward in time. When a particle is going backward in time, it is called an antiparticle.
Are Feynman diagrams real?
Feynman diagrams are a pictorial representation of a contribution to the total amplitude for a process that can happen in several different ways. Feynman diagrams are graphs that represent the interaction of particles rather than the physical position of the particle during a scattering process.
What happens when an electron collides with a proton?
The electron starts as a regular atomic electron, with its wavefunction spreading through the atom and overlapping with the nucleus. In time, the electron reacts with the proton via its overlapping portion, collapses to a point in the nucleus, and disappears as it becomes part of the new neutron.
Is Richard Feynman buried in Altadena?
This last December, I paid my respects at the grave of physicist Richard Feynman, interred with his wife Gweneth at the Mountain View Cemetery in Altadena, California. Today was calm and sunny though, and the cemetery is a beautiful spot to find yourself. …
What is a tree level Feynman diagram?
In higher order of perturbation theory the diagrams would contain loops of particles. These leading order graphs are called “tree-level”graphs (we confine ourselves to such tree-level graphs in these lectures). The quantum amplitude can be obtained by the application of the following Feynman rules: 1.
What is a vertex in Feynman diagram?
The basic interaction therefore appears on a Feynman diagram as a “vertex”—i.e., a junction of three lines. In this way the path of an electron, for example, appears as two straight lines connected to a third, wavy, line where the electron emits or absorbs a photon.
How is the strong interaction represented in a Feynman diagram?
At the most fundamental level, the strong force is an exchange force between quarks mediated by gluons. The use of Feynman diagrams to visualize the strong interaction involves primitive vertices with quarks and gluons.
How are quarks involved in the strong interaction?
The use of Feynman diagramsto visualize the strong interaction involves primitive vertices with quarks and gluons. Quarks interact with each other by the exchange of gluons; a primitive vertex in the Feynman diagram involves a change in “color” and can take the form
Which is involved in the decay of a down quark?
The decay of the down quark is involved in the decay of the neutronand in beta decayin general. Feynman diagrams of transformations Index Particle concepts
How long does it take for a quark to decay?
The interaction depicted here is responsible for binding quarks together into mesons and baryons, and responsible for holding protons and neutrons together to form nuclei. Particles can decay via the strong interaction, and if such a decay pathway is available to a particle, it decays very quickly – on the order of 10 -23 seconds.