my apologize,i have ever seen that anywhere to provide a quote. but i meant how two specific charges know when interact by attraction force or repulsion force?
you can use jaxodraw which is a win application for drawing feynman diagrams.
before using that u shoud have installed javaruntime on your system.
http://jaxodraw.sourceforge.net/download/pkgs/jaxodraw-2.0-1_bin.tar.gz"
What's the difference between "repulsion force carrier and
attraction force Carrier" in electromagnetism interactions?
We know that these two messenger photons should be
distinguished. But in what features and details?