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enter image description here

(Zoom in here to see the scales.)
About the result of plotting running of 3 coupling constant, we think that we should get the correct one(MSSM).

But we get discontinuity at $ M_{susy}$.

If there something wrong in our formulae? If you have the correct formulae of $1/\alpha$, please provide them for me.

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closed as too localized by Brandon Enright, akhmeteli, Waffle's Crazy Peanut, Qmechanic Jun 10 '13 at 12:05

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Hi, you can find the full 2-loop beta functions in Martin and Vaughn here: – sujeet Jun 10 '13 at 5:41
I can't read the scales on your plot well enough to see whether they are different. – Michael Brown Jun 10 '13 at 6:40

If you change the particle content of your theory, you need to take into account threshold corrections. In order to be consistent with two-loop running you should also calculate the one-loop threshold coefficients. I guess these will make up for your dicontinuity.

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What is meant by "consistent" here? Is it "making up for discontinuity"? – stupidity May 15 '14 at 20:53
No. "Consistent" here means that if you take into account corrections of order $\hbar^2$, you should take into account all corrections to $\hbar^2$, which includes the threshold corrections. – Neuneck May 17 '14 at 16:02
Ah I see they are of the same order. Thanks for clarifying. – stupidity May 18 '14 at 17:18

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