Symbol beta_i

The passage around this formula

…coupling constants “run,” meaning their effective strength depends on the energy scale Q at which they are probed, governed by renormalization-group equations of the schematic form $Q\,\frac{dg_i}{dQ} = \beta_i(g_1, g_2, g_3, y_t, \lambda)$. where the $\beta_i$ are calculable functions of all the couplings together. This is exactly the machinery Degrassi’s and Buttazzo’s teams used to run the Higgs and top couplings up to the Planck scale, and it is not evidence that anything is changing over cosmic time; a coupling’s value at 100 GeV and its…

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