- #1
arivero
Gold Member
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- 167
In standard, old-fashioned, Kaluza Klein theory we have new dimensionful parameters, the size of the compact dimensions, but they become dimensionless after quotient against the Plank size, so they become the adimensional coupling constants of the gauge groups associated to the symmetry of the compact dimensions.
Now, in the Standard Model we have another dimensional parameter, the electroweak scale (call it the electroweak vacuum, the mass of the Z, or the mass of the W; we can pass proportionally from one to another by using the adimensional coupling constants). When this parameter goes, in mass units, to zero the gauge group becomes SU(3)xSU(2)xU(1). When this parameter goes to infinity the gauge group becomes SU(3)xU(1). So in some sense this parameter interpolates between two different Kaluza Klein theories. But I can not see it in the standard setup. Can it be fitted somewhere? It should be of some value when considering GUT groups in the KK context.
Now, in the Standard Model we have another dimensional parameter, the electroweak scale (call it the electroweak vacuum, the mass of the Z, or the mass of the W; we can pass proportionally from one to another by using the adimensional coupling constants). When this parameter goes, in mass units, to zero the gauge group becomes SU(3)xSU(2)xU(1). When this parameter goes to infinity the gauge group becomes SU(3)xU(1). So in some sense this parameter interpolates between two different Kaluza Klein theories. But I can not see it in the standard setup. Can it be fitted somewhere? It should be of some value when considering GUT groups in the KK context.