Talk:Renormalization group

message: From this section it follows that for example temperature, pressure and volume are relevant observables. Translating back to the RG behaviour the magnitude of these observables is supposed to increase as the observed scale is increased. I don't see what that is supposed to mean. Perhaps someone could elaborate on this? --MarSch 12:27, 4 May 2006 (UTC)
thread_title:  Relevant and irrelevant operators, universality classes 

message: Shouldn't RG rather be a monoid, since a 1-element exists and semigroup is (not always, but often — and as well @wikipedia) defined without 1-element? --CHamul 10:24, 14 November 2006 (UTC)
thread_title:  Elements of RG theory 

message: Unfortunately, this article does a poor job of explaining RG in a context independent of any particular application. Notably missing from it is any mention of RG in Chaos/Complexity theory, where it is critically important in Feigenbaum's proof of universality for a class of functions giving rise to chaos under a period doubling route. The article also reads -- as do many Wikipedia articles on technical topics -- like it is intended for specialists (though I wouldn't know why they would want to read it), as it contains impenetrable references to a raft of other things that were defined elsewhere. Article authors need to recognize that non-specialists turn to Wikipedia for definitions, and that the articles like this are of poor quality unless they are intelligible to someone not immersed in the field.  —Preceding unsigned comment added by 98.228.35.247 (talk) 20:21, 21 November 2010 (UTC)
replies: text: Amen. David Spector (talk) 02:54, 4 March 2011 (UTC)
thread_title:  Too technical 

message: It would be nice if the anonymous 178.197.254.3 editor discussed the object of his persistent edits reverted by 
JRSpriggs, soundly, in my opinion. Gell-Mann and Low, in the reference cited,  went beyond formal solution of the finite renormalization group equation to an expression equivalent to the rise of the QED coupling with energy precisely as quoted in the 
LEP measurement.  Beyond mainstream professional opinion, Prof Harald Fritzsch stakes his professional opinion on it, 
in print (would 178.197.254.3 require the specific citation?  DOI:10.1142/S0217751X10049864).  Do S & P do so in the papers quoted, in such specificity? Do B & S? Is the paternity of this type fo prediction contested?  Please discuss, before tendentious repetitive repartee edits!   Cuzkatzimhut (talk) 20:35, 1 May 2011 (UTC)
thread_title: Physical Predictions

message: There is another article, Universality (dynamical systems), that seems to cover some of the same ground as this one when it comes to universality classes. Perhaps they should be merged, or at least more systematically linked to one another. Unfortunately the other article suffers from the same problem as this one regarding universality classes, in that it's purely descriptive, lacking technical information about what universality classes actually are and why they have the properties they do. 240F:7C:FC1A:1:D50E:E423:8FA7:F411 (talk) 01:49, 20 December 2014 (UTC)
thread_title:  Overlap with "Universality (dynamical systems)" 

message: Pls see Talk:Quantum field theory#Gratuitous removal of Ken Wilson's portrait. The fact that KGW is the one pioneer in the history of physics shaping the RG is not a matter of dispute, one hopes! Cuzkatzimhut (talk) 14:38, 1 March 2017 (UTC)
replies: text: I'm not sure which event you are talking about, but the history of this page suggests that copyright may have been the issue here.  Certain people watch like hawks to see if they can find something to remove.  In one case our lab photographer had to agree personally that the photo he had taken could be used, it being deemed insufficient for the dept. to give formal assent.  Fortunately he was still working at the lab and could give assent, but if he had retired that photo could not have been used! There was also a case of the reverse, where someone replaced the photos on a WP page by his own distinctly inferior ones, against the wishes of the photographees.  Fortunately he was persuaded to abandon his project and restore the originals. --Brian Josephson (talk) 11:00, 5 September 2017 (UTC)
replies: text: You might track the history down from the dates, May of this year, and especially the editing history of Ken Wilson's article.  [Ticket#2017032910014224]. Prof Paul Ginsparg of  Cornell provided ample approvals form the Physics Dept owning the pics, but, because they had appeared in the media during Wilson's Nobel prize celebration, the Wikimedia permissions' watchdogs were not satisfied. As a result the wold can easily find public domain pics of KGK through google image, but not through Wikipedia!  Cuzkatzimhut (talk) 15:30, 5 September 2017 (UTC)
thread_title: Gratuitous repeated removal of Ken Wilson's portrait

message: Incontrovertibly an invitation to WP:OVERSIMPLIFY... Lies to children... Of course the article is technical: it is the heart of quantum field theory. The relativity article and the Poincare group article and the QM mech articles are technical too to the novice, but it is absurd to pretend this is not unavoidable.  95% of mathematical articles here are too technical. Physicists start appreciating the RG after 4-5 years of technical schooling, and arguably fully master it after 20. 
Hopefully the template will add a few short words to the outsider, but, if the experience of several articles in WP is a guide, this appears like the beginning of a streak of uncontrolled erosion. More and more vapid nitpicking qualifying weasel words are added, which signal to crowds of fussing outsiders to come in and sculpt the narrative, and the end result is massive defocussing and detraction form the main "message" of the article, usually relegated to the end, and parts of the narrative the perpetrators normally decouple from. This is the routine progression of philosopher- and historian-infested articles like the Uncertainty principle, for instance, where regularly the focus is eroded in favor of lies-to-children bloviation---until a brave soul removes the underbrush in a spasm of righteousness.  This repetitive drama seriously compromises the quality and reliability of WP. Cuzkatzimhut (talk) 15:22, 11 August 2017 (UTC)
replies: text: Nevertheless, I'm sure the article can be made more readable without sigificant oversimplification.  For example, a possibility that occurs to me as I read it is that the technical comment on conformal transformations near the start could be moved to a footnote.--Brian Josephson (talk) 09:44, 5 September 2017 (UTC)
replies: text: You mean in the 2nd paragraph? Absolutely! Of course there is room for thoughtful  improvement.Cuzkatzimhut (talk) 10:40, 5 September 2017 (UTC)
replies: text: Yes. But I agree with your general point, and hence with your point of view that the article is not too technical, in the sense that it is only as technical as it needs to be to be useful in the way that an encyclopedia ought to be.  The situation may be compared with that of the Stanford Encyclopedia of Philosophy, which has articles that are pretty technical, as they need to be in order to enlighten readers.I guess the w'pedia procedure at this point would be to gather consensus.  If no one argues convincingly for a reduction in technicality then maybe that template can legitimately be removed. --Brian Josephson (talk) 10:50, 5 September 2017 (UTC)
replies: text: I would argue for the template to go, but not ardently. There could be contributors with preternatural communications skills who might be able to improve it, and, even though it lends the article an aura of a construction site, at least warns/scares-off the self-declared "gifted amateur" who wonders why they don't get it, past the lede. It's one of the deepest and most fundamental theories of theoretical physics, and expecting any quick-and-easy explanation in a couple of pages may simply not be possible. The grim history of the Uncertainty principle might illustrate what happens when readers get to expect that, or else...   Cuzkatzimhut (talk) 15:23, 5 September 2017 (UTC)

text:  For the record, though it may be five years late, "length scale" and "energy scale" generally the "natural units" of a system. To be formally precise: It is not generally meaningful to talk about a function of a dimensional quantity (a quantity with a unit like seconds), because we usually define such functions based on power series but it is meaningless to add 1s + 1s^2, for example. Fortunately -- or, arguably, as a direct consequence -- the laws of nature inevitably divide out all such quantities by a characteristic "natural unit" before actually using them in calculations. It is quite common to see an equation that, say, only ever depends on a ratio , where both  and  are lengths, and never on a bare  alone. In such a case, we would then refer to the quantity  as the "natural length scale" of the system. The most famous examples of such natural units are the Planck units, which are the natural scales of the Standard Model and general relativity as a whole, but smaller subsystems and theoretical models have their own characteristic scales. Linkhyrule5 (talk) 23:56, 8 April 2023 (UTC)

text:  I removed the template as it is no different from other similar physics entries, and there is clarity when one stops at the lede. Nonexperts should not complain for parts beyond the introductory sections. So it looks like the complaint is at the physics level on wikipedia, not this article. Maybe the solution is simplified Wikipedia. Limit-theorem (talk) 14:05, 22 March 2018 (UTC)
replies: text: Good move.  My impression is that several of these templates represent the frustration of an unclued reader who feels like shaking his fist at a field. As a participant of a Physics questions website, I can attest to the broad satisfaction of the bulk of physics students  with WP physics coverage, in some contrast to standard textbooks! I think an editor with salutary ideas needs no prompting by a template: she or he knows a sentence or a paragraph or a section is improvable. Cuzkatzimhut (talk) 22:24, 23 March 2018 (UTC)
thread_title: Recent "too technical" template

message: Electrons consisting of electrons(??????), positrons and photons. Bare electrons, dressed electrons, clothed electrons? It feels like someone is cheating here. Bad article ... again!!!  — Preceding unsigned comment added by Koitus~nlwiki (talk • contribs) 20:47, 26 October 2020 (UTC)
thread_title:  The down-fall of physics 

message: It is misleading to invoke the Avogadro number. The model space is something different and in principle can be much larger. For instance, the number of different chemical compounds consisting of C and H atoms grows more than exponentially with the number of atoms.
It is misleading to say that a relevant parameter "always grows". In what direction? In respect to what sign convention? Relevance, irrelevance and marginality describe the behavior in the vicinity of a fixed point.radical_in_all_things (talk) 17:10, 15 November 2021 (UTC)
thread_title:  Inconsistencies 

message: https://www.nature.com/collections/jbhcdccded
Maybe cite. 2601:644:8501:AAF0:0:0:0:2034 (talk) 00:35, 28 January 2024 (UTC)
thread_title:  Nature focus issue (Nov 2023)