Wikipedia talk:WikiProject Physics

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Facemasks

Physicist review of Face masks during the COVID-19 pandemic would be useful. Some related pages, like Vaporized hydrogen peroxide, which for some reason also covers H2O2 plasma, also need work. HLHJ (talk) 05:08, 13 May 2020 (UTC)

What part of that article are you concerned about? What issue depends on physics? JRSpriggs (talk) 00:02, 14 May 2020 (UTC)

Some eyes/opinions on a few points may help ...

Talk:Classical electron radius#Unsupported claim and Talk:Planck units#Conversions between units?. —Quondum 02:04, 14 May 2020 (UTC)

Hmmm. The former looks like it's becoming one of those time-sink disasters that generally make this whole project less fun and useful for everybody. It did, however, indirectly lead me to look up the fully relativistic expression for the electron-positron annihilation cross section, which has even more square roots in it than I had remembered:

${\frac {4\pi r_{e}^{2}}{\gamma +1}}\left[{\frac {\gamma ^{2}+4\gamma +1}{\gamma ^{2}-1}}\ln \left(\gamma +{\sqrt {\gamma ^{2}-1}}\right)+{\sqrt {\gamma ^{2}-1}}-{\frac {\gamma +3}{\sqrt {\gamma ^{2}-1}}}\right].$

This applies for decays into pairs of photons, not three or more, and which decay path predominates can depend upon, e.g., whether the positronium "atom" is in a singlet or triplet state. Fun! :-) XOR'easter (talk) 06:18, 17 May 2020 (UTC)

References

Hawking radiation

I noticed that Hawking radiation has a few "citation needed" tags for standard material that is probably explained in dozens of places, so if anyone has references that they find particularly good, those should be filled in. XOR'easter (talk) 14:58, 17 May 2020 (UTC)

Do we need to add them? There is a type of almost troll-like crank who goes around adding s where they are not really needed and wastes peoples' time. Xxanthippe (talk) 22:38, 17 May 2020 (UTC).

If you think they look superfluous and want to remove them, I won't object (say, if there's a citation at the end of a paragraph that covers the whole thing). XOR'easter (talk) 11:49, 18 May 2020 (UTC)

Since the citation needed tags seem to relate to requests for more information needed at that point, and if these are explained elsewhere as per Xxanthippe, then perhaps they should be replaced by links to the relevant sections of the article. —Quondum 13:27, 18 May 2020 (UTC)

Milgrom constant

A new article on a term that doesn't actually appear to be used, pertaining to a minority view of physics and cosmology. I redirected it to Modified Newtonian dynamics, but I'm not actually sure it's a term even people who care about MOND would search for, since there are orders of magnitude more MOND papers than instances of "Milgrom constant" or "Milgrom's constant". Maybe, maybe not. XOR'easter (talk) 22:02, 18 May 2020 (UTC)

Even our article on MOND calls the new fundamental constant "a₀", rather than "Milgrom's constant". JRSpriggs (talk) 07:37, 19 May 2020 (UTC)

Deletion debate for Relational approach to quantum physics

The discussion at Wikipedia:Articles for deletion/Relational approach to quantum physics may be of interest to the community here. XOR'easter (talk) 16:59, 20 May 2020 (UTC)

Fringe results at One-way speed of light

I undid ([1]) some i.m.o. questionable edits at One-way speed of light. See Talk:One-way speed of light#Fringe results. Eyes and comments welcome. - DVdm (talk) 16:19, 26 May 2020 (UTC)

Scipost

SciPost an open-access journal, has been deleted before. Somebody should check (now that it has more time out there) if its admissibility in Wikipedia has changed.--ReyHahn (talk) 20:23, 30 May 2020 (UTC)

Here is the old AfD. XOR'easter (talk) 13:10, 31 May 2020 (UTC)

Browsing through about half of the links that are not effectively self-published, the dominant patterns is that it is mentioned as an example of an entity in open access publishing model: the topic of most of the references is the model and not SciPost, and in all shows little more than existence of SciPost. I doubt that a keep case (i.e. notability) could be built. —Quondum 14:39, 31 May 2020 (UTC)

Yes, the sourcing seems rather poor. Passing mentions, not independent, etc. XOR'easter (talk) 23:18, 31 May 2020 (UTC)

List of American Physical Society Fellows

The other day, I saw that HRShami had created a List of American Physical Society Fellows, catching up to the analogous pages for other fields' learned societies (the IEEE, etc.). The list was incomplete, but I happened to have the data in parse-able form, so I filled it out and split it up chronologically for easier handling. I've tried to correct errors in the APS website data, probably due to typos or OCR mistakes, and I've turned many of the red links blue by identifying them with existing articles. If you're looking for a diversion, it's fun to flip through and look for familiar names. Either they can become articles, or perhaps they already are and just need a piped link. XOR'easter (talk) 19:49, 4 June 2020 (UTC)

Criticism on radiation of charged particles in a gravitational field

Can somebody fact check this edit [2] on Paradox of radiation of charged particles in a gravitational field.--ReyHahn (talk) 10:45, 8 June 2020 (UTC)

Articles for deletion: Quantum gravity: the integral method

Input welcome at Wikipedia:Articles for deletion/Quantum gravity: the integral method. - DVdm (talk) 14:13, 9 June 2020 (UTC)

I saw that while curating. Looked a little fringe, but didn't dig into it too closely. I've not heard of it, but quite a lot of strange things get published and I don't even try to follow them all any more. Lithopsian (talk) 14:20, 9 June 2020 (UTC)

Quark dispute

I'm unable to reach a consensus with 2 editors on the matter regarding free quarks. Therefore, I need input from a third party (other editors). I'm now unable to edit the article anymore due to it being locked, and I'm an IP.

Editor Cuzkatzimhut has a poor understanding of particle physics. He couldn't provide any valid counter-argument against my claim, which is backed up by many scientific experiments. See Talk:Quark#Free quark. It is clear that he tried to use circular reasoning and ignored all the scientific facts I provided.

Editor Ruslik0 claims that my sources are not reliable.

1. How is a published book not a reliable source? (source 1)
2. Source 2 is from CERN website. CERN has the largest particle physics lab in the world. It is leading the world in particle physics research.
3. Source 3 is from Forbes. Forbes is a well-known American magazine that explains science for the layman. Source 3 is written by a Ph.D. astrophysicist.

The information in the quark article was written over 10 years ago. It's outdated, and nobody has updated it for the last 10 years. Now, as physicists gain more understanding of the quarks, physicists discover things that they didn't know for sure before. There are many many sources that support my statement. Here are 3 more sources from many more in addition to the 3 sources above: from Livescience, from Lawrence Berkeley National Laboratory, and from European Commission, managed by European Union. It would be nice to hear input from editors that are actually particle physicists in real life or anyone with a deep understanding of particle physics.14.169.212.232 (talk) 10:09, 11 June 2020 (UTC)

In that conversation you seem employ personal attacks. Please remember to always assume WP:GOODFAITH, it helps to attain more straightforward discussions.--ReyHahn (talk) 10:27, 11 June 2020 (UTC)

Wikipedia:Assume good faith doesn't mean immunity to criticism when someone repeatedly ignores scientific facts. 14.169.212.232 (talk) 10:41, 11 June 2020 (UTC)

Although not strictly necessary, it may help if you create an account so that your edits appear under a single consistent name and it becomes easier to hold a sensible discussion. You appear to have edited under several different IP addresses and that creates a poor impression since it is an approach that can be used to try and hide your activity or circumvent blocks (not that you actually seem to be doing that). Lithopsian (talk) 10:52, 11 June 2020 (UTC)

I've never been blocked, and I'm not interested in creating a Wikipedia account. I don't edit Wikipedia often at all. I edit it occasionally (or rarely over the last 15 years) when I see an error while I read something on Wikipedia. The changing nature of my IP is not intentional. I edit Wikipedia at different locations. Also, my institution changes IP daily, not sure why, but it's how it has been. And, I don't plan to be highly involved in Wikipedia after this matter has been resolved. 14.169.212.232 (talk) 11:07, 11 June 2020 (UTC)

"Free quark" typically refers to an isolated quark in vacuum. A quark gluon plasma is not a vacuum. Quarks are free to move in a quark gluon plasma but that doesn't make them "free quarks". Cuzkatzimhut is right, you misunderstand the sources you quote, and then start to attack other users personally. I'm a particle physicist by the way. --mfb (talk) 11:00, 11 June 2020 (UTC)

Your argument is moot if you can't provide a reliable source to back up your claim. I got reliable sources to back up my claim. 14.169.212.232 (talk) 15:34, 11 June 2020 (UTC)

I'm sorry but my 6 stated sources above do not interpret "free quarks" that way. The scientific mainstream interpretation is that free quarks mean that quarks are no longer in color confinement. Give me one source that supports this interpretation, "Free quark typically refers to an isolated quark in vacuum." And isolated quarks just mean that quarks are free from color confinement. Basically, in this case, isolated quark and free quark actually mean the same thing. I got 6 sources that support my statement (and many more but 6 should be enough). I'm also a physicist. 14.169.212.232 (talk) 11:15, 11 June 2020 (UTC)

Also, the top quark has been observed DIRECTLY. Therefore, claiming quarks can never be observed directly is simply false. Like I said the information in the lede is outdated. It needs to be updated as physicists dig deeper into nature.14.169.212.232 (talk) 12:08, 11 June 2020 (UTC)

My proposal to fix the problem is to add "below the Hagedorn temperature" after the words "found in isolation". And the word only is deleted from "they can be found only within hadrons." You can't use the word only when that is not the only place that you find quarks! 14.169.212.232 (talk) 13:26, 11 June 2020 (UTC)

Mfb is correct. You have been stretching your sources beyond what they can actually support, and over-hyping the reliability of material like blogs and press releases. XOR'easter (talk) 14:36, 11 June 2020 (UTC)

Give me a source that says free quark means an isolated quark in vacuum. If you can't provide me a reliable source, your point is invalid. Which one of my sources is a blog? One of them is a published book. And some of my sources come from very respected institutions such CERN or European Commission. You're saying CERN, the leading institution in particle physics, is incorrect too? 14.169.212.232 (talk) 14:40, 11 June 2020 (UTC)

source 7 from Nature journal. Nature was the world's most cited scientific journal by the Science Edition of the 2018 Journal Citation Reports. This source also supports my definition of "free quarks", not yours. You guys are all talk. I haven't seen a single reliable source from you all that supports your claim while I've provided 7. You're going to say Nature journal is unreliable too? 14.169.212.232 (talk) 15:07, 11 June 2020 (UTC)

The Forbes source is a blog. The CERN thing you made a big deal of was basically a press release, as is the one from LBL. Those don't count for much. They build up claims of novelty and dumb down language. XOR'easter (talk) 15:50, 11 June 2020 (UTC)

Forbes source is not a blog. It has editorial review. Sure, it's not as rigorous as academic journal, but it's definitely not a blog. Plus, its author has a PhD in astrophysics; you can't fake credential on Forbes. Press release from one of the most respected institution in the world needs to be taken seriously. Words don't all of the sudden change their meaning in the press release. Your synthesis of word meaning is "original research". According to Wikipedia policy, no original research please. And lastly, how are you going to discredit Nature's paper? Nature journal is literally one of the most respected journals in the scientific community. And they support my point of view. Also, according to Wikipedia:Reliable sources, secondary and tertiary sources are preferred. Press release is secondary source. 14.169.212.232 (talk) 17:04, 11 June 2020 (UTC)

The Forbes source is literally from a blog called "Starts With a Bang". That blog happens to be hosted on Forbes now; it was on ScienceBlogs.com back in the day. Moreover, Siegel is a Forbes "contributor", meaning that he is not subject to editorial oversight. As a physicist, he's a better self-published source than many; as an astrophysicist, he's in a field that is adjacent to what we really are interested in here. XOR'easter (talk) 17:54, 11 June 2020 (UTC)

Okay, let's agree that Forbes source is out, but I still got 6 remaining sources (there are many more on google, but 6 should be enough). They are reliable according to Wikipedia:Reliable sources, and secondary sources are preferred over primary sources. 14.169.212.232 (talk) 18:27, 11 June 2020 (UTC)

You wanted input from particle physicists, and once you got it you dismissed it immediately because it wasn't in your support. Great approach. I added the quark gluon plasma to the article (at the time of my first comment) and we can think about adding a sentence about the top quark - which decays before hadronization - but what you want to put into the article is wrong. --mfb (talk) 14:34, 11 June 2020 (UTC)

Did you even read what I wanted to add into the article before saying I'm wrong? Adding the quark-gluon plasma was the good first step, but that doesn't resolve all the problems. Anyway, a problematic sentence taken from the quark article, "Due to a phenomenon known as color confinement, quarks are never directly observed or found in isolation; they can be found only within hadrons." Claiming all quarks can never be directly observed is scientifically incorrect, the top quark proves it's wrong. And claiming quarks can only be found within hadrons is also scientific incorrect. Quarks can also be found in quark-gluon plasma. The word "only" needs to be deleted. 14.169.212.232 (talk) 14:56, 11 June 2020 (UTC)

(edit conflict)If I understand correctly, IP is saying that aside from the technicalities of quark-gluon plasma and Hagedorn scales, quarks can sometimes be found free (not forming hadrons)? and that the discovery of single top quarks is an example, is that it? --ReyHahn (talk) 15:13, 11 June 2020 (UTC)

My claim is that free quarks, free from color confinement, are found in the quark-gluon plasma (quarks don't form hadron in this plasma). And second claim, all quarks can never be directly observed is a scientifically incorrect statement. Third claim, isolated quarks mean the same thing as free quarks in this case. Fourth claim, the word "only" needs to be deleted from "found only within hadrons". 14.169.212.232 (talk) 15:22, 11 June 2020 (UTC)

I am trying to build your argument here. So first point, do we agree that quark-gluon plasma is a very particular case? Do you mean your second point only based on QG plasma? Three is just wording, ok, but are you considering the quarks in QG plasma "free/isolated"? Fourth, the word found where?--ReyHahn (talk) 15:49, 11 June 2020 (UTC)

First point proves that free quarks exist outside of hadrons. Second point based on the top quark. Third point is related to this claim in the quark article, "quarks are never directly observed or found in isolation." Quarks can never found in isolation is not true. It's just wording yea, but the wording has important implication. Fourth point is related to this statement in the quark article, "they can be found only within hadrons." The word "only" needs to be deleted to make it a true statement because first point proves "only" is incorrect. 14.169.212.232 (talk) 16:45, 11 June 2020 (UTC)

I guess the examples of QG plasma and of the top quark are exceptions that have to be discussed on their own in the lead. Maybe we may find a wording that satisfies better the objections but that leaves a clear picture of the importance of confinement.--ReyHahn (talk) 17:14, 11 June 2020 (UTC)

I agree that QG plasma and top quark are exceptions that should be discussed on their own. However, that doesn't mean it's accurate to make general claim that is scientifically incorrect. One cannot make a claim that all quarks can never be directly observed when top quark is a quark! One also cannot make a claim that quarks are found only within hadrons when scientists have also found them elsewhere namely the QG plasma. 14.169.212.232 (talk) 17:42, 11 June 2020 (UTC)

IMO, simultaneously claiming that the top quark can be detected "directly" and that it decays too quickly to hadronize would confuse the reader. Indeed, carelessly throwing around the word "direct" is apt to mislead, particularly since top-quark-detection events are usually classified by the decay products of the W bosons that the top quarks decay into. Moreover, I think jamming too much detail about top-quark decay rates into the lead of the article would overburden what is supposed to be a concise summary. The article does mention decay-before-hadronization down in the body. That should be expanded first (probably with more and better references) before we do anything else on the topic. XOR'easter (talk) 16:15, 11 June 2020 (UTC)

You're missing my whole point. I'm not saying to add that fact about top quark in the lede. What I'm saying is that "quarks are never directly observed or found in isolation; they can be found only within hadrons" should be changed into "quarks are never directly observed or found in isolation below the Hagedorn temperature; they can be found within hadrons." "Below the Hagedorn temperature" is added while "only" is deleted. I'm not sure why people keep resist my change despite my overwhelming reliable sources. I feel like I'm being treated unfairly because I'm an IP and not an established editor. Established editors are not always right. 14.169.212.232 (talk) 17:29, 11 June 2020 (UTC)

What funny is that I'm basically saying the same thing as in the article color confinement. Let's take a look at a quote taken from that article, "color-charged particles (such as quarks and gluons) cannot be isolated, and therefore cannot be directly observed in normal conditions below the Hagedorn temperature." No one seems to object to that, but people got a problem when I try to add the same fact into the quark article. Is this evidence of owning the content or discrimination against IP (editors without an account)? 14.169.212.232 (talk) 17:37, 11 June 2020 (UTC)

I can't speak for anybody else, but I personally don't care that you're "not an established editor" and you're editing from an IP address. You've pointed to a place where an article legitimately needed clarification (and, in passing, where its references needed updating). Quark-gluon plasma deserved to be mentioned more prominently; thanks to Mfb, this is now taken care of. But you've been persistently confrontational (e.g., this edit summary, and trying to impose your preferred version before a consensus has been obtained), and you've misrepresented the quality of the sources you've presented. That will raise hackles regardless of whether you're an "established editor" or not. XOR'easter (talk) 18:03, 11 June 2020 (UTC)

First of all, you didn't discredit all of my 7 sources. You successfully discredited 1. I didn't misinterpret the quality of my sources. They are as reliable as you can get in the particle physics field. No one can argue that CERN or Nature are not reliable. In any case, 6 reliable sources is greater than 0 source provided by you.

Second, I've been basically saying the same thing as a statement in color confinement, yet it is not allowed to use that statement in the quark article. How do you explain that? Or are you trying to say the information in the color confinement is scientifically incorrect?

Third, the statement, "quarks are never directly observed or found in isolation; they can be found only within hadrons" is problematic (as in scientifically incorrect). It should be changed into "quarks are never directly observed or found in isolation below the Hagedorn temperature; they can be found within hadrons." I've proven repeatedly with reliable sources why the first statement is problematic, but it seems like some editors just simply refuse to accept scientific facts. 14.169.212.232 (talk) 18:43, 11 June 2020 (UTC)

Perhaps it would help to deal with some of these separately. I see no problem with removing "quarks are never observed directly" or "they can be found only within hadrons", since these seem questionable. The idea of isolation can be dealt with separately; stating this suitably may be a challenge, so leave this for last. —Quondum 19:39, 11 June 2020 (UTC)

Agreed! I'm the same IP guy btw. My new proposal is to change the old statement ("quarks are never directly observed or found in isolation; they can be found only within hadrons") into this, "quarks are never found in isolation below the Hagedorn temperature; they can be found within hadrons." Technically speaking, top quark is found in isolation below the Hagedorn temperature, but I can live with it being an exception to the confinement law of nature. However, claiming it can never be directly observed while the contrary has been proven is not OK. 2402:800:4368:7FA6:DC73:9475:FC7F:1743 (talk) 20:05, 11 June 2020 (UTC)

Now you are introducing claims about isolation. The Color confinement article does not link temperature to isolation as you are doing, it only links the ability to observe them to it. It states that quarks cannot be isolated, period. This is consistent with a normal interpretation of "isolation"; no quark is isolated in a hadron or in a quark plasma. —Quondum 20:35, 11 June 2020 (UTC)

It does link temperature to isolation. Isolation here means break free from color confinement yes? Above the Hagedorn temperature, quarks are indeed isolated from their color confinement. Theoretically, quarks can be observed directly above Hagedorn temperature. Granted that scientists haven't been able to do that (maybe in a few years). The idea that quarks can never be isolated is called confinement. This idea breaks down in quark-gluon plasma (above the Hagedorn temperature). 14.169.100.161 (talk) 04:43, 12 June 2020 (UTC)

Source to show that isolation is linked to temperature. 14.169.100.161 (talk) 05:18, 12 June 2020 (UTC)

Looking at the lead of Quark, I see nothing wrong since this edit. I am now not seeing anything but a reinterpretation of the language that would give rise to your objections. You mentioned the Color confinement article as saying what you want, but your proposal is not the same as what is in that article. —Quondum 21:23, 11 June 2020 (UTC)

The lead currently says, they can be found only within hadrons, which include baryons (such as protons and neutrons) and mesons (all of which are unstable and short-lived), or in quark–gluon plasmas. So, no, there's no need to remove the "only" — the full sentence makes the meaning clear. I don't think we need to remove never directly observed or found in isolation, either, since all the observations are indirect. XOR'easter (talk) 22:31, 11 June 2020 (UTC)

Claiming all observations are indirect is simply false. Some observations are indirect, yes. The top quark has been observed directly. source 1 (a published book in particle physics), source 2 (another published book in particle physics). Therefore, never directly observed needs to be removed. 14.169.100.161 (talk) 04:48, 12 June 2020 (UTC)

Those are two copies of the same passage recycled by the same author, so it's really only one source, and it's talking about observations that are indirect by the standards that are relevant here. (That is, it is describing something that was less indirect than prior measurements as "direct".) Compare and contrast with 1: It is well-known that, once produced, top quarks decay very rapidly. For this reason top quarks are observed and studied indirectly through kinematic features of their decay products. XOR'easter (talk) 06:40, 12 June 2020 (UTC)

What do you mean? They are two separate published books with different authors. Those are 2 different independent reliable sources that both claim that the top quark has been observed directly. You need a reliable source to back up your claim that the top quark has never been directly observed.

Your source didn't say this, "That is, it is describing something that was less indirect than prior measurements as 'direct'." You made it up on your own. No original research please.

You misinterpret your source to prove your point, which is false. Your source concerns with "QCD corrections and jet radiation in top quark decays" only. That is not the same experiment that was directly observing the top quark. Top quark spin's effect could be measured directly, hence physicists around the world say it has been directly observed. They didn't say the same thing about the other 5 quarks. Whatever standard of your made-up indirect you're trying to prove, you need to prove your assertion with a reliable source. I've proved mine, where is yours? 14.169.100.161 (talk) 08:28, 12 June 2020 (UTC)

Agreed on not removing the only and never found in isolation. However, what point is being made by including never directly observed? Surely we are dealing with an ill-defined concept "directly observed", plus the point being made is surely that they are never observed as separate/isolate particles? —Quondum 23:11, 11 June 2020 (UTC)

You might surely recall that, before the advent of jet physics, the "confirmation" of the physical existence of quarks was through the parton model interface of DIS, an apotheosis of indirection. Indirection and forced hadronization are still the cornerstones of our understanding of quarks. Physics has hardly had to cope with anything as paradoxical and subtle. Cuzkatzimhut (talk) 00:13, 12 June 2020 (UTC)

Yes, there was something qualitatively more indirect about quarks than about anything in particle physics before. XOR'easter (talk) 01:46, 12 June 2020 (UTC)

The discussion of what an indirect observation is a rabbit hole if ever there was one. To get back to my point: what is it that we are trying to say with that statement that is encyclopaedic? Are quarks more indirect to observe than is the Higgs field? Or the W and Z bosons? All that the claim tells a reader is that quarks, like many other particles, play hard-to-get. It gives no standard for comparison. —Quondum 02:12, 12 June 2020 (UTC)

Incontrovertibly quarks are substantially less direct to detect than the Higgs particle--Not field!-- and gauge bosons. That is the central point in the lede. It suffices to bring it up for the interested reader; you can't really explicate it in detail, when their "reality" baffled the best minds of the 70s. Cuzkatzimhut (talk) 02:54, 12 June 2020 (UTC)

There are indirect observation of free/isolated quarks in the quark-gluon plasma (above Hagedorn temperature). Therefore, below the Hagedorn temperature needs to be added after "found in isolation".14.169.100.161 (talk) 04:57, 12 June 2020 (UTC)

Problem arises when it's not clear that the word isolation here means within the context of the lede. Isolation from what? Isolation from color confinement or isolation in the vacuum? Those are not the same thing! If isolation here means free quarks then below the Hagedorn temperature needs to be added.

If isolation here means isolated quark in the vacuum then a clarification is needed. The statement should say quarks can never be isolated in the vacuum. I would be ok with this change. 14.169.100.161 (talk) 05:43, 12 June 2020 (UTC)

The first paragraph of Quark already mentions QGP; we don't need to pile more unfamiliar terminology like Hagedorn temperature on top of that. XOR'easter (talk) 06:40, 12 June 2020 (UTC)

Unfamiliar to whom? Anyone who is familiar with quarks would also be familiar with Hadedorn temperature. Making an absolute claim in science like never without clarification is not okay. In fact, it becomes a scientific incorrect statement. Just because QGP is mentioned, that doesn't negate the fact that the statement is false without clarification. 14.169.100.161 (talk) 08:35, 12 June 2020 (UTC)

In the voice of our favorite bunny Max, "that is the most ridiculous thing I have ever heard". People generally learn about quarks in high school (possibly elementary school). Hagedorn temperature on the other hand will likely only appear in advanced undergraduate or graduate courses in particle physics. So the group of people familiar with the term quark is probably at least three to four orders of magnitude bigger than the those how have heard of the Hagedorn temperature. Needless to say to former is our target audience, not the latter.TR 11:24, 12 June 2020 (UTC)