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by spekcular 1516 days ago
The person who wrote that paper doesn't understand the basics of the field that he's talking about.

For example (from the blog post): "Consa gives an analogy wherein Indian mathematician Srinivasa Ramanujan has claimed that the sum of all positive integers is not infinite, but is instead -1/12. It’s wrong, it’s absurd, but renormalization has now been accepted, and is even sold as a virtue."

One when performs zeta function regularization, one gets -1/12. This isn't some mystery; it's a perfectly reasonable thing to do. Analytic continuation has been understood since the 1800s.

Reference: https://en.wikipedia.org/wiki/Zeta_function_regularization

Edit: I read more of the linked paper. The claim that Karplus and Kroll committed "fraud" is basically libel, as can be seen by reading the complete account. The worst one can say is that people didn't publish full details of calculations due to page limitations or laziness, but this is hardly a special feature of QED. For instance, Onsager famously solved the 2-d Ising model exactly in 1944 but never provided details in print, just the final solution.

1 comments

Onsager was a bastard with omitting details. He has a 1949 paper on packing of hard rods (and other anisometric particles), which is 4 pages long, but a colleague who went through the details of the derivation spent half a year and filled a ring binder with intermediate calculations.
Damn.

I never actually learned this stuff. Is there a good textbook account of this isotropic-to-nematic transition that includes full details? Or is there still a gaping hole in the published literature?

In other words, did your colleague do this as a kind of history project, or because the details weren't available anywhere else?

I don't think there are textbooks on this stuff, it is too much of a niche, you probably need to read journal papers. A place to start might be the classic "What is liquid?" review paper by Barker and Henderson:

https://link.aps.org/pdf/10.1103/RevModPhys.48.587?casa_toke...

... and then the classic review paper on liquid crystals by Stephen and Straley:

https://link.aps.org/pdf/10.1103/RevModPhys.46.617?casa_toke...

But I believe the "gaping hole" as you call it has been mostly filled by the recent work. You probably still need to spend some weeks to follow along though.

The motivation for my colleague was to develop the Onsager theory further, since Onsager only went to the second virial coefficient. They were able to go to higher-body contributions and get nice algebraic results for the equation of state, IIRC. I can probably dig up the DOI if you want to read it.

Yes, I'd love to read it, if you have time to find the DOI. Thanks!
Thanks!
I wonder if this is a consequence of people demanding more "rigor" nowadays?
Well with electronic form it is now quite trivial to include the derivation, so no real reason not to publish it or at least a detail set of steps so demanding more rigor seems fair.