A modern view of forces - HEP Educational Outreach

... exchange of photons between the electron and the proton. • The strength of that interaction is directly proportional to the EM coupling constant, aem! • In general, all force carriers will “couple to” particles with some “strength”. – The particle in question must have the “right charge” (more on th ...

... exchange of photons between the electron and the proton. • The strength of that interaction is directly proportional to the EM coupling constant, aem! • In general, all force carriers will “couple to” particles with some “strength”. – The particle in question must have the “right charge” (more on th ...

QCD and Nuclei

... As long as you let it be the most general possible Lagrangian consistent with the symmetries of the theory, you're simply writing down the most general theory you could possibly write down. ... “ “F-proof”: It’s hard to see how it can go wrong ...

... As long as you let it be the most general possible Lagrangian consistent with the symmetries of the theory, you're simply writing down the most general theory you could possibly write down. ... “ “F-proof”: It’s hard to see how it can go wrong ...

Transparancies for Feynman Graphs

... QED – mediated by spin 1 bosons (photons) coupling to conserved electric charge QCD – mediated by spin 1 bosons (gluons) coupling to conserved colour charge u,d,c,s,t,b have same 3 colours (red,green,blue), so identical strong interactions [c.f. isospin symmetry for u,d], leptons are colourless so d ...

... QED – mediated by spin 1 bosons (photons) coupling to conserved electric charge QCD – mediated by spin 1 bosons (gluons) coupling to conserved colour charge u,d,c,s,t,b have same 3 colours (red,green,blue), so identical strong interactions [c.f. isospin symmetry for u,d], leptons are colourless so d ...