Scaling and the renormalization (sub)group

[Carlos L. Janer]

I am aware of only two fields where the renormalization (sub)group ideas can be systematically and
unambiguously applied: particle physics and equilibrium critical behaviour.

1.- Are there any others?

2.- What are these ideas used for in fluid mechanics?

3.- When cosmologists speak about 'electroweak phase transition' what do they really mean? Is it just the fact
that Higg's field vacuum expectation value changed to a non null value and its symmetry was spontaneously
broken?

I am not quite sure where I should be posting this.

 

[jambaugh]

1. There are general symmetry methods for differential equations which include scaling transformations to find first integrals. See e.g. Olver's "Application of Lie Groups to Differential Equations".

2. I've not worked enough in the area of fluid mechanics to answer.

3. I believe that's exactly it.