P28 of phase transitions and the renormalization group

AI Thread Summary
The discussion focuses on a potential error in Nigel Goldenfeld's "Lectures on phase transitions and the renormalization group," specifically on page 28 regarding the computation of potential energy for a uniformly charged sphere with a non-standard interaction potential. The concern is that the change of variables from (x,y) to (u,v) does not properly restrict the range of u to the intersection of two unit spheres translated by distance v. Additionally, the final result does not align with the expected outcome for the case when σ=2. This discrepancy is not addressed in the book's errata, leading to uncertainty about the correctness of the calculations. The participants agree that this may indicate a mistake in the text.
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Hi,

I'm confused about the discussion on p28 of Nigel Goldenfeld's "Lectures on phase transitions and the renormalization group" (this question can only be answered by people who have access to the book.)

The goal is to compute the potential energy of a uniformly charged sphere where the interaction potential goes as 1/r^\sigma (So Gauss's law isn't valid). I think that, after the change of variables (x,y) -> (u, v) he neglects to restrict the range of u to the intersection of two unit spheres that are translated a distance v with respect to each other. The final result of the computation also does not agree with the case \sigma=2.

This is however not mentioned the errata (http://guava.physics.uiuc.edu/~nigel/errata.html) so maybe I'm missing something.Thanks,

A_B
 
Seconded. I think it is a mistake.
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks

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