A Feynman diagram of a strong proton-neutron interaction mediated by a neutral pion with the individual quark constituents shown, to illustrate how the fundamental strong interaction gives rise to the nuclear force. Straight lines are quarks, while multi-colored loops are gluons (the carriers of the fundamental force). Other gluons, which bind together the proton, neutron, and pion in-flight, are not shown.

Click this LINK to visit the original image and attribution information. Right click on the image to save the 800px teaching JPEG.



A Feynman diagram of a strong proton-neutron interaction mediated by a neutral pion with the individual quark constituents shown, to illustrate how the fundamental strong interaction gives rise to the nuclear force. Straight lines are quarks, while multi-colored loops are gluons (the carriers of the fundamental force). Other gluons, which bind together the proton, neutron, and pion in-flight, are not shown.