Entries by Bill Hobba

Why Renormalisation Needs a Cutoff

Introduction This is a follow on from my paper explaining renormalisation. A question was raised – why exactly do we need a cut-off. There is a deep reason to do with dimensional analysis, and the power series expansion used in perturbation theory. Along the way we will see renormalisation in a more general setting, and…

Renormalisation Made Easy

What Is The Issue With Renormalisation If you have an interest in physics you have likely come across renormalisation before, although what it really is would probably have not been explained.  Instead you would read Dirac never accepted it, Feynman called it a ‘dippy process’, and if you look under a quantum theorists rug you…