It looked to me like the entire original post was about how you couldn’t use lower level laws to extrapolate higher level laws. Renormalization is the only way I know of to do this. Additionally, every comment in this direct thread is about renormalization. I think renormalization is the topic.
Renormalization is a very specific technique, mostly used in HEP, to work around the infinities cropping up into the calculations. It does not let you predict anything about a lower-energy model from the higher-energy one, only to replace “bare” quantities with the renormalized ones.
It looked to me like the entire original post was about how you couldn’t use lower level laws to extrapolate higher level laws. Renormalization is the only way I know of to do this. Additionally, every comment in this direct thread is about renormalization. I think renormalization is the topic.
Renormalization is a very specific technique, mostly used in HEP, to work around the infinities cropping up into the calculations. It does not let you predict anything about a lower-energy model from the higher-energy one, only to replace “bare” quantities with the renormalized ones.