On the other hand, solutions to this equation for large initial values formula_33 cause the "rhs" to quickly approach smaller values as we descend in energy scale. The above equation then locks formula_33 to the QCD coupling formula_31. This is known as the (infrared) quasi-fixed point of the renormalization group equation for the Yukawa coupling. No matter what the initial starting value of the coupling is, if it is sufficiently large it will reach this quasi-fixed point value, and the corresponding quark mass is predicted.