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## Main Question or Discussion Point

I have two questions.

But first here's the context of my questions in the following excerpt from Peter Woit book Not Even Wrong:

"Why SU(3)xSU(2)xU(1)? A truly fundamental theory should explain where this precise set of symmetry groups is coming from. In addition, whereas QCD (the SU(3) part of this) has the beautiful property of having no free parameters, introducing the two other groups SU(2) and U(1)) introduces two free parameters and one would like some explanation of why they have the values they do. One of these is the fine structure constant a, and the question of where this number comes from goes back to the earliest days of QED. Another related concern is that the U(1) part of the gauge theory is not asymptotically free, and as a result it may not be completely mathematical consistent."

my questions

1. Please share any arxiv (etc.) papers about why SU(3)xSU(2)xU(1) and anything you have heard about where this precise set of symmetry groups is coming from? It looks like numerology, you know the 3-2-1.

2. Peter Woit is asking why U(1) part of the gauge theory is not asymptotically free. In QCD.. it's asymptotically free. So what would happen if U(1) is also asymptotically free? Please describe the dynamics. And why should it and why an un-asymptotically free U(1) may not be completely mathematical consistent?

But first here's the context of my questions in the following excerpt from Peter Woit book Not Even Wrong:

"Why SU(3)xSU(2)xU(1)? A truly fundamental theory should explain where this precise set of symmetry groups is coming from. In addition, whereas QCD (the SU(3) part of this) has the beautiful property of having no free parameters, introducing the two other groups SU(2) and U(1)) introduces two free parameters and one would like some explanation of why they have the values they do. One of these is the fine structure constant a, and the question of where this number comes from goes back to the earliest days of QED. Another related concern is that the U(1) part of the gauge theory is not asymptotically free, and as a result it may not be completely mathematical consistent."

my questions

1. Please share any arxiv (etc.) papers about why SU(3)xSU(2)xU(1) and anything you have heard about where this precise set of symmetry groups is coming from? It looks like numerology, you know the 3-2-1.

2. Peter Woit is asking why U(1) part of the gauge theory is not asymptotically free. In QCD.. it's asymptotically free. So what would happen if U(1) is also asymptotically free? Please describe the dynamics. And why should it and why an un-asymptotically free U(1) may not be completely mathematical consistent?

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