RUNNING COUPLING CONSTANTS!








The electromagnetic coupling becomes stronger at shorter distances or higher momentum transfer, because electron-positron pairs have less chance to shield the (infinite) “bare” charge; for the strong force the opposite effect occurs because the quarks are in a sea of virtual gluons, and the closer one gets to a quark, the fewer gluons are nearby.  Remember QΔr = ℏc.





Measurements of α and αs as a function of momentum transfer.




When the 1/(mass)2 factor that makes the weak force appear so weak is factored off, in the limit as the momentum transfer goes to zero, the “true” weak αW is about 1/30, 4.5 times stronger than α.


A hint of a unified theory... but forever beyond the reach of experiment, at an energy of 1014 GeV!  This hint sent theoretical physics into a dead end path lasting 55 years so far, the quest for a GUT.
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