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Talk:Loop quantum gravity

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?? question ??
am i wrong if i'd suggest to replace "space" by "SPACETIME" in many places, f.e.: Loop quantum gravity (LQG) is a theory that attempts to describe the quantum properties of the universe and gravity. It is also a theory of quantum space and quantum time because, according to general relativity, the geometry of spacetime is a manifestation of gravity. LQG is an attempt to merge and adapt standard quantum mechanics and standard general relativity. The main output of the theory is a physical picture of space where SPACETIME is granular. The granularity is a direct consequence of the quantization. It has the same nature as the granularity of the photons in the quantum theory of electromagnetism or the discrete levels of the energy of the atoms. Here, it is SPACETIME itself that is discrete. In other words, there is a minimum distance resp. TIME-STEP possible to travel through it. (=> each of the four dimensions are granular... ) ... as well as i found in many articles/places "(havy) matter" as the only reason for "bending/curvation of the spacetime" ! Shouldn't it be "matter or energy" at every place as both are equivalent ? — Preceding unsigned comment added by TheuDie (talk • contribs) 12:45, 27 December 2014 (UTC)

Yes, you are wrong. LQG models *sapce* using a spin-network, and it predicts that there is a quantum of area, and probably a quantum length. LQG does not work that well with time, and it is not clear in any way that there is a quantum of time in the same way as there are quanta of space.WKB2020 (talk) 09:35, 20 June 2021 (UTC)

12 year old
Isn't it wikipedia policy for a 12 year old to be able to understand... I'm 12 years of age and my dad (37) couldn't understand a word of it except for the words a, the, it, in, science, gravity and physics! please... can this srticle be simplified!

Then why don't you go to Simple English Wiki kid? That's clearly your and your father's level. —Preceding unsigned comment added by 99.227.131.13 (talk) 04:16, 25 November 2010 (UTC)

 * The relevant question is -- is the Wikipedia sufficiently self-contained for a patient enough and diligent enough person (even 12) to find answers needed? You don't need to understand something to understand it. You only need to have access to the background needed to understand it. But the background is part of the Wikipedia, too. You can literally start out at 0 (as long as you're able to read, that is) and work your way from there.

 * I always understood that's how people normally surf the web anyhow (especially younger people for whom this is supposedly their home turf!). When they don't get something they surf in a matter of milliseconds to another link to bone up on what background they don't know, and then go back to what it was whose background they didn't have.

 * I think the answer is -- the Wikipedia (and the net, as a whole) are completely self-contained ... even to the point (I might add) of making school and college redundant and superfluous. -- Mark, 2007 February 3 —Preceding unsigned comment added by 4.159.171.124 (talk) 23:32, 3 February 2008 (UTC)
 * That's the dumbest statement I've ever read. I shudder at the thought of the newer generations being educated by the internet. 201.216.245.25 (talk) 19:26, 25 November 2009 (UTC)
 * "a matter of milliseconds"? I assume you live somewhere that has Fiber-To-The-Home? Jimw338 (talk) 22:27, 23 September 2015 (UTC)

Also, this article has gained WWW status as "difficult to understand"

 * Please sign your comments in the future. The fact of the matter is that LQG is a very esoteric piece of theoretical physics.  As such it cannot be explained to a 12 year old unless that 12 year old knows tensor calculus.  When I was 12 I was busy learning the basic laws of motion and general analytical skills which helped me learn what I needed in order to understand topic such as these. --Hfarmer 06:28, 13 July 2007 (UTC)

 * Absolute rubbish. This obviously bright 12 year old is quite right and you are wrong.  There is a perfectly comprehensible description of this field in the January 2004 issue of Scientific American that does not use the word 'tensor' once.  Like I said, I have a PhD in solid state chemistry and I found the article totally incomprehensible.  Don't blame the igonorance of the audience for your lack of expository skills.  Deadlyvices 10:16, 14 July 2007 (UTC)

 * Your education... I really don't see what that has to do with the topic at hand. You learned chenistry and not nearly as much physics as a physicist would.  Please respect the fact that solid state chemistry while complex is not physics, that little you know would be applicable.  I certinaly would not pretend to know as much about solid state chemistry as you would.  Please pay us, your fellow physical scientist, the same respect.  Furthermore I have not edited this article's copy in a long time.  When I did I gave it the structure of having a plain english introductory lead section, then more technical guts.  It still has that basic structure.  Does it not say.

Loop quantum gravity (LQG), also known as loop gravity and quantum geometry, is a proposed quantum theory of spacetime which attempts to reconcile the seemingly incompatible theories of quantum mechanics and general relativity. This theory is one of a family of theories called canonical quantum gravity. It was developed in parallel with loop quantization, a rigorous framework for nonperturbative quantization of diffeomorphism-invariant gauge theory. In plain English, this is a quantum theory of gravity in which the very space in which all other physics occurs is quantized.

Loop quantum gravity (LQG) is a proposed theory of spacetime which is constructed with the idea of spacetime quantization via the mathematically rigorous theory of loop quantization. It preserves many of the important features of general relativity, while at the same time employing quantization of both space and time at the Planck scale in the tradition of quantum mechanics.

LQG is not the only theory of quantum gravity. The critics of this theory say that LQG is a theory of gravity and nothing more, though some LQG theorists have tried to show that the theory can describe matter as well. There are other theories of quantum gravity, and a list of them can be found on the quantum gravity page.

 * Just what about that is confusing? where is the word tensor used? There is really no way to make it simpler than the above.  Any simpler and the article would be so generic as to be applicable to any theory of quantum gravity.   --Hfarmer 13:25, 14 July 2007 (UTC)

 * Sorry, I should have said I found it almost totally incomprehensible. You don't appear to grasp that the issue is not about education, it's about meeting your audience halfway, and you don't seem to be prepared to budge an inch. Why should I have to be a physicist to understand a Wikipedia article?  Kind of makes the writing of it in the first place pretty pointless, wouldn't you say?
 * I came here looking for a good, clear account of the subject for the intelligent layperson and I found this instead. It's chock-full of material such as

At the core of loop quantum gravity is a framework for nonperturbative quantization of diffeomorphism-invariant gauge theories, which one might call loop quantization. While originally developed in order to quantize vacuum general relativity in 3+1 dimensions, the formalism can accommodate arbitrary spacetime dimensionalities, fermions,[1] an arbitrary gauge group (or even quantum group), and supersymmetry,[2] and results in a quantization of the kinematics of the corresponding diffeomorphism-invariant gauge theory. Much work remains to be done on the dynamics, the classical limit and the correspondence principle, all of which are necessary in one way or another to make contact with experiment.

In a nutshell, loop quantization is the result of applying C*-algebraic quantization to a non-canonical algebra of gauge-invariant classical observables. Non-canonical means that the basic observables quantized are not generalized coordinates and their conjugate momenta. Instead, the algebra generated by spin network observables (built from holonomies) and field strength fluxes is used.
 * 'In a nutshell, loop quantization is the result of applying C*-algebraic quantization to a non-canonical algebra of gauge-invariant classical observables. ' Just what the hell does all this mean? The most impenetrable of nutshells, that's what. I may be a chemist but even with my limited knowledge (which extends to Fermi levels, wave vectors, k-space, Brillouin zones and the suchlike) I imagine I could write a far more accessible account which, although lacking this kind of mathematical detail, reaches a much wider audience.  Yet when someone points out that the article is largely incomprehensible, you reply 'As such it cannot be explained to a 12 year old unless that 12 year old knows tensor calculus'.  You might as well have said 'go away and play with your Newtonian mechanics, little boy/girl'.  If you want to be accorded respect, try showing it in the first place, and to everyone, not just 'fellow physical scientists'.  I'd suggest that you start by always underestimating your audience's knowledge and never underestimating their intelligence.  This article and your subsequent comments seem to do the complete opposite. Deadlyvices 04:14, 16 July 2007 (UTC)
 * I am sure your education in chemistry is quite comprehensive. I have no doubt that in that field you are totally qualified.  I would have to differ with your assertion that you know enough about this topic to write a good article about it.  While you know much about quantum levels of atoms and what not (more knowledge of that than the average physicist to be certain).  That kind of "quantum physics" has little to nothing to do with the ultra relativistic quantum mechanics that is LQG (Or M theory for that matter).  If you had said you knew Quantum Field Theory that would have been a much stronger credential.

 * However I understand that this is not about credentials. Wikipedia needs to be understandable to everyone who has graduated at least highschool.  That is how I had written the introductory paragraph and subsequent editors continued in that spirit.

 * To make this article comprehensible to a 18 year old the article could only consist of that introductory section.

 * I suggest this look at the references in the LQG article. Read and study the matterials then please tell me how to break this down without mentioning tensors, or calculus, or the calculus of tensors, or the algebra of operators, etc, etc.  It is inherently very complicated.  THAT'S NOT MEANT TO INSULT YOU.  It's just a statement of facts.  LQG is second in complexity only to M-theory.  That's just the nature of Quantum Gravity. --Hfarmer 05:16, 20 July 2007 (UTC)

 * So, are you telling me that there is no middle ground between the article remaining as it is, that is to say, more or less incomprehensible to anybody without a background in relativistic physics, and it being so superficial that it conveys no usful information whatsoever? That, to be of use, it only is of use to professional theoretical physicists?  Give me a break!
 * The article on Heim Theory also deals with a very complicated and dense subject, probably understood by even fewer people than LQG. Yet I was able to understand all of it, not just the introductory paragraph.  This is because the person who wrote it is evidently better at communicating difficult subject matter than the people who wrote this article.  I'd bet real money that an entry written on LQG by a comparative non-expert would reach a bigger audience than this one and end up doing more ultimate good for the cause.  Don't forget;  it's the plebs like me who ultimately pay the salaries of the theoreticians who work in this field and we have every right to know why this field is worth bothering about.  The 12-year-old you patronised may well end up being your Senator one day.Deadlyvices 16:53, 20 July 2007 (UTC)

 * Yes. That's what I am saying.  At the level of physics a 12 or even 18 year old knows LQG and M-theory would be indistinguishable.  For such a person they would probably stop with reading about "quantum gravity".  To be a real smart @$$ I will say that a 12 year old Richard Feynmann would understand just fine. :P--Hfarmer 19:55, 16 September 2007 (UTC)

 * I tend to concur with the other Richard Feynman, the one who said that if a subject wasn't explicable in a freshman lecture, then it hadn't been understood properly.  Every other article I've read on the Web about LQG manages to convey much more than this one.  I wonder why that is?Deadlyvices 07:33, 23 September 2007 (UTC)

 * Like most big Wikipedia topics (Star Wars, Pokemon, computational chemistry...) it's written largely by fans and experts in its particular field, and therefore generally written with a certain amount of assumed knowledge about the field, rather than being aimed at a general audience. It's easy to forget that Wikipedia is meant to be an encyclopedia, and not just a collection of all human knowledge. Technical depth can (and arguably should) be dropped for clarity and brevity, so long as proper references and a bibliography are provided. 137.195.68.169 16:35, 25 October 2007 (UTC)

I agree that the quantum physicists who author these tutorials have little interest in writing down to the layman level since they are playing to their peers, academics who will recognize thier thumbnail descriptions on wiki almost like publications. It is not impossible to explain something this arcane to laymen with some background in math (just read Roger Penrose's article on loop gravity in "Road to Reality") but for a 12 year old without the knowledge of vectors, guage connections, parallel transport, spin networks, etc. it just isn't possible. Piamero (talk) 05:19, 22 September 2008 (UTC)piamero

I think that this piece of the whole article does a better job that this wikipedia article in explaining what loop quantum gravity is. —Preceding unsigned comment added by 62.77.56.12 (talk) 11:38, 9 December 2009 (UTC)

While I have the greatest respect for people who strive to document these complex topics, I wholeheartedly agree with Deadlyvices' objections. Abstract physical concepts that are very difficult to understand have been documented to accommodate readers of nearly all levels, which means this article is unnecessarily complicated. The greatest physicists of all time were able to make earth-shattering discoveries because of their ability to think in physical pictures like speeding trains and such. The most famous example is probably the apple falling on Newton's head. I know that this becomes rather difficult when talking about non-Newtonian physics, but Albert Einstein also thought in 'physical pictures', even though the subjects he studied were far more abstract than gravity. I strongly suggest you take it upon you to represent the intensely abstract LQG with more 'graspable' presentations. Highly respected scientists like Michio Kaku do a great job at publishing literature on advanced scientific concepts that is understandable by pretty much anyone. That said, I'm not telling you to drop the more complex content. I'm merely asking you to at least provide interested readers who do not study physics with a solid explanation of the basics of LQG, significantly increasing the importance and value of this article. — Preceding unsigned comment added by 81.243.33.132 (talk) 18:34, 24 August 2011 (UTC)

Should there be another LQG entry simplified for popular understanding in popular press?

http://en.wikipedia.org/wiki/String_theory For a generally accessible and less technical introduction to the topic, see Introduction to M-theory. — Preceding unsigned comment added by 75.81.141.8 (talk) 03:35, 16 March 2013 (UTC)

I like complicated

 * As an "educated layman" i enjoy being challenged and stimulated by wikipedia physics entries and i'd like to suggest that as long as technical terms are linked to their respective articles, allowing users to investigate to whatever depth they feel comfortable with there should be no attempt to simplify to any great extent - some things are just bloody complicated.

58.105.150.204 (talk) 04:50, 21 January 2008 (UTC)
 * Jolly good for you. Most of us, when we start off learning about a new subject, prefer 'simple'.  And 'comprehensible'.  We also don't like having to engage in wild-goose chases across the Web trying to ascertain the meaning of material that could quite easily have been made easy to understand in the first place. Perhaps you have a lot of free time to do this sort of investigation.  I don't, personally, and if Wikipedia wants to be recognised as any kind of authoritative resource, it has to be accessible before sets out to be rigorous.Deadlyvices (talk) 18:57, 29 January 2008 (UTC)
 * Cool story bro. Fact is, this material has to be abstracted and generalized to the point of distortion in order for it to be 'easy to understand'. The problem is egotistical readers expecting to be able to easily understand whatever they come across, certain that their vast intellects are surely capable of grasping any given topic instantly. If they don't understand something, it's not their fault - it's the material's! Pathetic. Unsigned, because, well, fuck you that's why.
 * Well, bro, I don't expect anything of the sort. Most people, not me, think that this article is jargonistic and poorly written,  and if a professional scientist like me finds it difficult it's not because I'm egotistical to the extent that I expect everything to be handed to me on a plate.  Perhaps we have a point.  Perhaps its written by a crappy author who is too arrogant to recognise he isn't very good at explaining complex topics.  Perhaps it shouldn't be written about at all in an encyclopaedia if it can't be written about comprehendably.  And fuck you too, you arrogant, abusive and cowardly little man (that much I'm certain about).  Deadlyvices (talk) 22:33, 20 July 2011 (UTC)

Just revisited this page. Up until the section *Constraints and their Poisson bracket algebra* it's pretty good. After that it's totally incomprehensible, over-technical shit. Deadlyvices (talk) 11:53, 7 July 2015 (UTC)

 * I find much of this article incomprehensible. I don't begrudge the presence of the complicated detail as well, but there should be an introductory section that is more clear and simple, without unnecessary jargon. I read A Brief History of Time at age 12 and understood it as far as it went, so I'm certain that exceedingly complicated and unintuitive concepts can be explained at least a little better than this article does. 2601:441:4680:3230:8049:1915:7B9F:826A (talk) 15:01, 13 June 2019 (UTC)
 * Sixteen years on from my original gripe, and whoever wrote this article managed to make it even more dense and incomprehensible.
 * That's one hell of an achievement.
 * Deadlyvices (talk) 12:33, 20 October 2023 (UTC)

Iyo Iyo Ita
Why are we citing non-peer reviewed, and seemingly unphysical (multiplication of functionals=0 is just wrong) material? Surely we should only cite journal papers, not just what gets posted to arxiv! —Preceding unsigned comment added by 71.58.64.44 (talk) 01:35, 17 March 2008 (UTC)

 * The way things are done these days arxiv, is the way allot of physics publishing is done. Some on there don't even bother with paper journals anyway because more people will see an arxiv posting.  Another way is to put it on a scientific bloging site, or on your website then a moderated usenet group.  From there feedback and peer review is public.  By the time something is in a paper journal these days it is old news. --Hfarmer (talk) 02:27, 21 July 2008 (UTC)

Please nobody take this suggestion seriously. I am a professional chemist and the idea that there are scientist that "dont even bother with paper journals anyway" or that personal websites or "scientific" blogs are reliable sources, is laughable.178.15.151.163 (talk) 13:44, 18 February 2016 (UTC)

Chiral fermion anomalies
It currently appears that nothing forbids coupling anomalous - i.e. quantum mechanically inconsistent - chiral fermions to LQG.
 * That's not true, LQG is based upon first class constraints and with anomalous chiral fermions, the first class constraints mutate into second class constraints. AnonyScientist (talk) 11:38, 23 August 2008 (UTC)

Block of original research removed
I've removed the block of original research and synthesis posted in the section previously titled "Diffeomorphism invariance and background independence", and replaced it with what I suppose is an equivalently imperfect summary-style section, presently retitled Loop quantum gravity. ... Kenosis (talk) 23:34, 8 January 2009 (UTC)

I proposed the following be removed to their own sections/articles

* 4.4 LQG and the big bang singularity * 4.5 LQG and particle physics * 4.6 LQG and the Graviton * 4.7 The Kodama state * 4.8 Spinfoam * 4.9 Non commutative geometry and loop gravity

 * 1) 5 LQG and analogues to condensed matter physics

* 5.1 LQG and string nets * 5.2 LQG and group field theory —Preceding unsigned comment added by 134.193.253.41 (talk) 18:26, 9 March 2009 (UTC)

any volunteers to do so? If I do so will someone reverse the edit? —Preceding unsigned comment added by 134.193.253.41 (talk) 18:33, 9 March 2009 (UTC)

is interpretation Fermi results controversial?
Pra1998 added a reference to a paper about results from Fermi, stating in the article that they "seem to have severe implications for this theory." Is this noncontroversial? There's a recent paper by Amelino-Camelia and Smolin http://arxiv.org/abs/0906.3731 analyzing the results, which does not seem to say "Oh no, we need to give up on LQG." --76.167.77.165 (talk) 02:20, 18 August 2009 (UTC)

I think it is at this time premature to rely on a single observation. —Preceding unsigned comment added by 24.145.243.18 (talk) 18:07, 19 August 2009 (UTC)

The good, the bad, and the ugly
I am a layman who has more than passing interest in this topic. I would like to chime in with my two cents.

The good
This is a remarkably well-balanced article in a field in which every researcher thinks he/she has THE answer. Theory is not confused with fact. Limitations are admitted. Contrary opinions are acknowledged. All objectively presented. Kudos to the contributors. I would like to see this objectivity maintained in future editions.

The bad
The article is almost completely impenetrable. It's not the concepts; it's the vocabulary. My favorite sentence is:
 * "While originally developed in order to quantize vacuum general relativity in 3+1 dimensions, the formalism can accommodate arbitrary spacetime dimensionalities, fermions, an arbitrary gauge group (or even quantum group), and supersymmetry, and results in a quantization of the kinematics of the corresponding diffeomorphism-invariant gauge theory."

This is a cutting-edge subject--some level of knowledge must be assumed. The article cannot go all the way back to explaining photons, electron, protons, and neutrons--that would require an entire encyclopedia. However a better balance needs to be achieved between precision and comprehension. Some suggestions: shorter sentences; fewer "BIG" words per sentence; more analogies; more examples. I don't think a professional physicist is needed--just writing each sentence with conscious attention to the target audience.

The ugly
There is no ugly!

 * The para you quoted can be understood by anyone with even a basic understanding of basic physics, . Dimension10 (talk) 13:53, 23 July 2013 (UTC)

Uh-huh? So "formalism", "supersymmetry" and "gauge theory" are all part of your "basic understanding of basic physics"? You must be super-duper smart.178.15.151.163 (talk) 13:47, 18 February 2016 (UTC)

I have a high school level physics i got a B in when 17, so basic physics....definitely didn't mention "diffeomorphism-invariant" I agree with the original comment 79.64.152.157 (talk)  —Preceding undated comment added 23:51, 29 January 2020 (UTC)

Citation needed?
I was a bit surprised by the following in the article, "...as of now there is no experimental observation for which loop quantum gravity makes a prediction not made by the Standard Model or general relativity (a problem that plagues all current theories of quantum gravity)." Could someone provide a citation for this as i thought LQG did make a prediction which was supposed to be tested by GLAST. —Preceding unsigned comment added by 24.222.119.180 (talk) 21:57, 15 May 2011 (UTC)

You are quite right, looking for it as I write.
It was the question if a photons 'speed' could vary with its 'energy' that GLAST was supposed to look for, amongst other things. In loop quantum it seems as if this could be a effect of the theory, not invalidating Einstein, but modifying it slightly. Although, be aware of that we are discussing 'energy', as defined from interactions, not 'rest mass'. So those of you wanting to give a photon a 'mass' have to search elsewhere. .. Can't seem to find anything recent though? http://www.slac.stanford.edu/exp/glast/ground/GlastScience/year2007/JeffScargle/JeffScargle_jan11_07.pdf discuss it. And here is GLAST http://fermi.gsfc.nasa.gov/ .. The best I could find is from 2008 .. http://www.douban.com/group/topic/8577816/ but? I'm surprised that I can't find anything better on it. It should be resolved by now, one way or another..

Ahh a.. http://backreaction.blogspot.com/2010/08/update-on-status-of-dsr.html Hmm :) But, I do like Smolin, he's what all scientists should be, open to change, keeping his cool. Theories are only as good as the experiments proving or disproving them. And Smolin is constantly at the forefront, no matter how controversial he might be deemed to be. Still, as I expect light to be a 'clock' of sorts myself, I'm happy that we haven't found it with several 'beats', not that it's impossible, though. Here is the link to the wiki http://en.wikipedia.org/wiki/Doubly_special_relativity (deformed special relativity) that seems to discuss that idea in more depth, hopefully :)

Yoron 178.30.80.59 (talk) 17:51, 25 June 2011 (UTC)

Formula?
What's the central formula of this theory? I mean, there has to be something likem a Lagrange density or something similar... --91.4.236.151 (talk) 18:08, 20 July 2011 (UTC)

 * Yup, the Einstein - Hilbert - Palatini - Ashtekar (EHPA) or Einstein - Hilbert - Ashtekar (EHA) action (Source: LQG for (and by) the bewildered) .. Dimension10 (talk) 13:56, 23 July 2013 (UTC) . m.

 * Would there be something like a (quantum) physical system, with a Hilbert space of states or whatever is appropriate for LQG, and observables and dynamics? You would be looking for the formula for dynamics of the system? --Telecomtom (talk) 01:33, 3 April 2012 (UTC)

 * From the article on spin networks: "In loop quantum gravity (LQG), a spin network represents a "quantum state" of the gravitational field on a 3-dimensional hypersurface. The set of all possible spin networks (or, more accurately, "s-knots" - that is, equivalence classes of spin networks under diffeomorphisms) is countable; it constitutes a basis of LQG Hilbert space." Maybe someone will write the formula for the dynamics ... --Telecomtom (talk) 02:08, 3 April 2012 (UTC)

Overlooked aspects and gaining information
Some large aspects of this theory have been seriously overlooked, this article only explains the very basics of loop quantum gravity and a lot more information is needed to give the reader a sufficient understanding of this theory. I'm a physicist, and I'm new to wikipedia, but an expert is not the the only option, for example i can't really help because i specialize in string theory and occasionally other similar fields. But the truth is that anyone, given they put in a sufficient amount of time and research can construct an understanding of anything, well enough to give a brief outline of it. A large population of the planet have vast amount of information at their disposal, everyone reading this has access to the internet, this allows us to research near enough any topic we desire, including quantum loop gravity. It may be hard to find but i can assure you, it is there. All we need is a team of people, maybe even just one person to research this topic, their understanding to begin with is irrelevant, as long as they put in enough effort to begin with and gain an interest in the desired topic. This person, or people, could then update this page with their findings, sure it would help if there was a specialist who could explain it without research, but the notification that one has been needed has been up there for 2-3 years, so we will have to do the next best thing. Someone with a respectable amount of knowledge of physics could do this brilliantly, they could grasp the concepts of this theory easily, and identify, false or misleading data. I have a 'quite' good understanding of this theory and if no one steps up and does this research I will do it myself, if i have the time. Dr J. Hill — Preceding unsigned comment added by Joehill11 (talk • contribs) 20:59, 6 February 2012 (UTC)
 * Well, hurry the frick up, Doc - and when you get going, leave me a note on my Talk Page so I can follow along behind you as your assistant, tweaking your grammar! :-)

Welcome to Wikipedia! We can use you! And BTW, if you know any lung cancer experts, send them to me - I NEED THE HELP!

Very best regards: Cliff (a/k/a "Uploadvirus") (talk) 11:47, 8 February 2012 (UTC)

black hole entropy contradictions
the below 2 passages contradict one another, Carlo Rovelli's edit is based on more recent research which does away with the Immirzi parameter and Carlo Rovelli is a LQG researcher who has written papers and textbooks.

I propose deleting the older bottom paragraph as no longer current.

Another application of LQG concerns understanding the thermal behavior of black holes. A recent success of the theory in this direction is the computation of the entropy of all non singular black holes [16]. The result is the expected formula S=A/4, where S is the entropy and A the area of the black hole, derived by Bekenstein and Hawking on heuristic grounds. This is the only known derivation of this formula from a fundamental theory, for the case of generic non singular black holes.

Another problem is that a crucial free parameter in the theory, known as the Immirzi parameter, can only be computed by demanding agreement with Bekenstein and Hawking's calculation of the black hole entropy. Loop quantum gravity predicts that the entropy of a black hole is proportional to the area of the event horizon, but does not obtain the Bekenstein-Hawking formula S = A/4 unless the Immirzi parameter is chosen to give this value. A prediction directly from theory would be preferable.

Vandalism 180.149.8.81
Main article: History of loop quantum gravity

In 1986, "someone" reformulated Einstein's general relativity in a language closer to that of the rest of

changed that to twitch

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i think someone should undo 180.149.8.81 vandals and then lock the article only ibyan and rovelli may add content ban 180.149.8.81

Time in general relativity
Under "The problem of time in quantum gravity", the introduction states:

"Roughly speaking the problem of time is that there is none in general relativity. This is because in general relativity the Hamiltonian is a constraint that must vanish. However, in any canonical theory, the Hamiltonian generates time translations. Therefore we arrive at the conclusion that "nothing moves" ("there is no time") in general relativity."

This is probably a reflection of Rovelli's thinking ("Forget time", "Time does not exist"). The claim that there is no time in general relativity as such is inappropriate, however, as it is at odds with generally accepted descriptions of general relativity. — Preceding unsigned comment added by 217.162.239.196 (talk) 22:54, 24 March 2014 (UTC)

 * The Problem of Time section belongs on a separate page, and should be removed from this page. I submitted a request for a "Problem of Time" page ( http://en.wikipedia.org/wiki/Wikipedia_talk:Articles_for_creation/Problem_of_Time ) and added a link to that proposed page as a "main article" link.  — Preceding unsigned comment added by 81.71.198.114 (talk) 12:34, 27 April 2014 (UTC)

The loop quantum gravity diffusion limit
In loop quantum gravity there is a limit of ultimate compression and then the Universe bounces for it isn't allowed any greater compression, but nobody cares because dark energy is proliferating faster than dark matter which loses energy.

Loop quantum gravity predicts that there is also an upper limit to the diffusion of space, and the excessive energy fills the missing matter thus we have a new Big Bang, but not out of any singularity. — Preceding Lee Smolin comment added by Lee Smolin (talk) 02:17, 28 April 2016 (UTC)

MathML problem
There is some equation on the page which doesnt render, can someone familliar with mathml and lqg take a look and see what is wrong? MiCkE 09:41, 24 June 2016 (UTC)

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Another citation needed?
I have anotated 'In 1986, Abhay Ashtekar reformulated Einstein's general relativity in a language closer to that of the rest of fundamental physics' with. My *guess* is that: Ashtekar, Abhay (1986). "New Variables for Classical and Quantum Gravity". Physical Review Letters. 57 (18): 2244–2247 is appropriate, but someone who knows should check that. 31.52.252.245 (talk) 14:42, 5 May 2019 (UTC)

Multiple redundant footnotes
72 through to 79 and 80 through to 81 are all the same, how do i delete these down to a readable number? thanks :D — Preceding unsigned comment added by Transmission Medium (talk • contribs) 12:02, 11 August 2019 (UTC)
 * Im seconding this, .... I see the footnotes and I could easily delete them, but Im holding off because they look like they were deliberately stacked there and it's possible that there's something I'm not seeing. — Soap — 23:54, 11 April 2020 (UTC)

My intro altered
In a recent edit User: MosquitoBird11 wrote

"Reverting intro to an older more user friendly and concise version before wordy and off topic WP:TOPIC edits by User:Ibayn and 200.104.142.8 which made the introduction difficult to comprehend, and overly focused and in-depth string theory."

Sorry but your intro:

"Loop quantum gravity (LQG) is a theory of quantum gravity, merging quantum mechanics and general relativity, making it a possible candidate for a theory of everything. Its goal is to unify gravity in a common theoretical framework with the other three fundamental forces of nature, beginning with general relativity and adding quantum features. It competes with string theory that begins with quantum field theory and adds gravity."

is inaccurate! Loop quantum gravity is not a theory of everything! And doesn't pretend to be. What you are describing by "Its goal is to unify gravity in a common theoretical framework with the other three fundamental forces of nature" is applicable to string theory but not to Loop Quantum Gravity, and as such you being are off topic.

And my intro:

"Loop quantum gravity (LQG) is a theory of quantum gravity, attempting to merge quantum mechanics and general relativity, (including the incorporation of the matter of the standard model into the framework). It takes seriously the key insight from general relativity that space-time is a dynamic entity, not a fixed framework. It competes with string theory that is also is a candidate for a theory of quantum gravity. However, unlike string theory, LQG is not a candidate for a theory of everything the goal of which is to explain all of particle physics, unifying gravity with the other forces at the same time. In contrast to LQG, string theory (for the most part) is a background-dependent (built on a fixed framework), which doesn’t account for the dynamic nature of space-time at the heart of relativity."

is accurate. It is not off-topic at all, what I am eluding to is the driving force (pardon the pun) behind Loop Quantum Gravity research! A very different philosophy to (most of) string theory.

Encyclopedias aren't necessarily supposed to be user-friendly but they are supposed to be accurate! User: IBayn.

 * First off, please don't use all caps because it almost seems as if you're shouting at people and we at Wikipedia are civil in our "conversations" :)  Secondly, I agree with you, but your solution does focus wayyyy too much on string theory and almost the entire second half could be cut. Third, Encyclopedias **are** supposed to be user-friendly. Otherwise, we could just list a series of sources and you could learn everything you wanted from them. If you want, we could brainstorm a better way to incorporate the issues you've brought up in a manner that doesn't ruin the tone, focus, friendliness, and reliability, of the lead. Integral Python click here to argue with me 15:29, 4 October 2019 (UTC)

I have edited my comments to tone things down User: IBayn.

I have altered the intro - now a compromise between accuracy and reader-friendliness. Please note there is an important difference between:

"incorporation of the matter of the standard model into the framework established for the pure quantum gravity case"

and

"unifying gravity with the other forces at the same time."

Unifying forces has a specific meaning, for instance, the electric and magnetic forces were understood as different aspects of the same force, i.e. the electromagnetic force. This unified the electric and magnetic forces. Loop quantum gravity does not attempt to explain gravity and the other forces as being different aspects of an all encompassing single force. In fact gravity is not a force User: IBayn.
 * I fixed it up a little bit to make it clearer and deemphasize string theory a little bit more, hopefully, I didn't re-add any of your original problems back. Integral Python click here to argue with me 22:02, 8 October 2019 (UTC)
 * Also, are you aware that your signature is not your actual user page? Your signature leads to User: IBayn, but your user page is User:Ibayn and your talk page is User talk:Ibayn Integral Python click here to argue with me 22:08, 8 October 2019 (UTC)

What does 3! mean?
In the section Loop_quantum_gravity we have a math equation with a 3! in it. I assume this is the factorial, which is 6, but why don't we just write 6? Is there a narrow use of excalamation points in math that Im not aware of? — Soap — 23:50, 11 April 2020 (UTC)

Make paragraph: Probabilistic loop quantum gravity
Not a single connectome of loops exists, but a Feynman set of alternative loop-connectome, with variant significance per section and as a whole (the whole is all mathematically similar or parallel universes; but nowadays we have a problem with very different mathematically nonparallelizable universes which do not belong in our own family of universes; thus don't immediately contribute probabilistically). — Preceding unsigned comment added by 2A02:587:410B:3A70:D92B:AEE6:8B9F:491E (talk) 13:52, 27 September 2020 (UTC)

Last part about granulation of spacetime is misleading?
Note the statement "ESA's INTEGRAL satellite measured polarization of photons of different wavelengths... ...13 orders of magnitude below the Planck scale." at the very end.

This statement is quite misleading, and I was questioning it when I first read it, since we cannot physically measure below planck length. I did further digging and apparently this is a quite wrong interpretation/statement and has been refuted on Physics StackExchange a more than a year ago. How should we fix this? I'm afraid if I add anything it would be more complicated than necessary. Captain Chicky (talk) 23:36, 25 November 2022 (UTC)

Loop Quantum Cosmology and its links with LQG
Affirming that "The most well-developed theory that has been advanced as a direct result of loop quantum gravity is called loop quantum cosmology (LQC)" is absolutely wrong. LQC is not a direct result of LQG in any way. LQC quantises "a la LQG" symmetry reduced models, it is not a direct result from taking LQG and reducing it to a symmetric spacetime. Even though it seems LQC and LQG might be conected (there are some papers by Livine, Tambornino, Garay... on simple models of LQG that show dynamics similar to those of LQC), affirming that LQC is a result of LQG is misleading. Alvinero (talk) 10:13, 18 May 2023 (UTC)

Theory and hypothesis
It would help very much if theory and hypothesis are not used interchangeably.

Loop quantum gravity is still a hypothesis. It might be described mathematically, but as far as I understand, it still explains nothing, can not be used for predictions and it is not yet possible to test it.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Talk:Loop quantum gravity


text:
Talk:Lindisfarne

Article title
✅ The OS maps call this island Holy Island, Lindisfarne appears to be an old name. I would like to change the lede to reflect this, is that OK? and can the map be used as the reference? Op47 (talk) 18:09, 19 May 2013 (UTC)
 * The full title is "The Holy Island of Lindisfarne" so either "Holy Island" or "Lindisfarne" are acceptable abbreviations, neither is "the old name". You might want to use the full title in the lead, but be aware that at least one editor regards using the official title as subjective and prefers the phrase "also known amongst some as Holy Island" so do try to avoid an edit war! Martin of Sheffield (talk) 15:46, 4 August 2013 (UTC)
 * I've run down references to the official name and the use of the shorter Holy Island so this should now be uncontroversial. Martin of Sheffield (talk) 19:20, 4 August 2013 (UTC)

Added small pieces of information
Hello users, I am a student from the University of Bergamo and I am taking part in a project that consists in giving a contribution to Wikipedia pages (https://en.wikipedia.org/wiki/Wikipedia:GLAM/UNIBG/Heritage_studies_and_ICT). In this page in particular I added a few more details about the attack on the island by Vikings in 793 (the fate of the monks), about the date of burial of St Cuthbert 's body on the island and also about the wooden boats that can be seen today (including also a picture already existing in Wikipedia). — Preceding unsigned comment added by Mcava19 (talk • contribs) 17:51, 8 January 2021 (UTC)

Holy Island of Lindisfarne
Can we discuss this please? changed it away from Holy Island of Lindisfarne and changed it back. I don't know Zac though I am sure they are great; Martin is usually super-reliable on UK place stuff. The claim for the Holy Island of Lindisfarne name, though, which as I write is used as the Official name, seems to rest on the assertion of the local website manager. Whilst I am sure they are sincere and do a great job, I am less sure that they are necessarily a WP:RS especially for something to which we give Official status. I would be much much happier with the assertion that Holy Island of Lindisfarne = Official name if it came from an official source. And if it is, then surely it can? I will have a look, and would be grateful if others also please would. Otherwise I think we may need to discuss the future of this usage. Really official = great; one website's idea = less great. I wonder if we can make it stick as the former.

For the record – I seem to always get colleagues patiently explaining how they speak fluent BrE and know the area, so obviously I am just higgerant and prolly not worth talking to  – I do speak an almost-intelligible form of a rather basic English and I may have been in that area once or twice, and I have not personally (yes, negative WP:OR!) come across this assertion of the Official name. It is rather nice, though, and I am happy to look for a source for it, with – I hope – your help! Best to all, DBaK (talk) 11:47, 4 August 2021 (UTC)

 * Hi DBaK. Thanks for the complement!  More seriously I've just plugged "Holy Island of Lindisfarne" into DuckDuckGo and (ignoring a couple of adverts) the first three websites are the local tourist information people, a local visitor company and Visit Northumberland, the county councils tourist site.  There's also a set of "Images for holy island of lindisfarne" some of which give one abbreviation, some the other and some the full name.  At the risk of OR, yes I did live near there! Martin of Sheffield (talk) 12:02, 4 August 2021 (UTC)

 * The long-form name isn't especially common and I'm not sure it qualifies as an "official" name because a few tourism websites use it. The Ordnance Survey simply calls the place "Holy Island", with "Lindisfarne" as a subtitle. Additionally, it strikes me as long-winded to begin the article by listing each name twice. In deference to Martin, I'll admit that I'm not local, though I am on holiday in the area at the moment (in fact, I'm writing this from the island). Zacwill (talk) 13:31, 4 August 2021 (UTC)

 * Considering that one of the sites is the county council it would seem fairly official to me. There are several other places where the long name is always abbreviated.  Who ever, in conversation, talks about "The Royal Borough of Kensington and Chelsea", or "Royal Tunbridge Wells" and nearer, "Kingston-upon-Hull".  Lucky you though staying on the island, I keep trying to persuade the "other half" to stay on overnight. Martin of Sheffield (talk) 14:16, 4 August 2021 (UTC)

 * Hi again and . I am very sorry that I have been absent from this discussion for such a long time – that pesky Real Life intervened, I had to do some work etc. I have not, however, done absolutely nothing about this issue. I have looked at and dug around on a number of sites that deal with place names and a number of official sites that deal with Northumberland. If you go to OS Open Names you can download a nightmare-huge CSV file and in it you will find Holy Island all the way down at D38246 (!) but no mention of Lindisfarne. You can also find stuff like this but I am not sure we would call it an RS anyway? As we already know the OS map itself just shows Holy Island as the place name with Lindisfarne in lovely archaic-item script, and of course it's in the name of structures on the island, but that in my opinion is as far as it goes. Martin, with the greatest of respect, and I am really not kidding about that, I can't accept your sources as reliable. The two local sites I simply discard because a webmaster can say anything they like and it means nothing: I can put up a site this afternoon called "The Leafy Suburb of Crouch End" or "The Steel City of Sheffield", indeed to increase my credibility I can put up six that use the terms ... it doesn't make them official though, it makes them a website's whim. (Addendum, hoping it's OK to add this as it's recent and there is no response yet ... the article itself summarizes it quite neatly thus: The combined phrase The Holy Island of Lindisfarne has begun to be used more frequently in recent times, particularly when promoting the island as a tourist or pilgrim destination. My point exactly. Concoction <> Official Name. Shutting up again now.)

 * I must further – and again I do so as nicely as I can! – dispute that the Northumberland tourism site constitutes a reliable source. It's marketing speak, it's been put together by people with serious professional concerns and care for their task but encyclopaedic accuracy is not one of them. Last time I looked it used, in some other places, the term "Lindisfarne Island" which is just bl**dy nonsense that no-one ever says! If you then start to look at more of their text and you see egregiously bad work that would not survive a week if you or I had edit permissions, then ... well, it just makes me go GAH frankly. I am sure it is great at its job of marketing but I cannot take it seriously as a source of hard data on a placename. Find me a serious Northumberland local government website that says it administratively and I will try to be nicer. But not in marketspeak.

 * I am aware that I am sounding ranty and a little unhinged about this and I don't want to be rude but I honestly think that the formulation is little more than a piece of marketing, or image, cuteness. Of course people like it and use it – it is sort-of lovely that you can concatenate the two placenames and get something with a nice historic ring to it. I am sure that the private webmasters involved will have their own reasons for this and I bet the tourism site does too. But this is all miles away from it constituting an Official Name. I am just not seeing it and, believe me, I have looked.

 * As I am in danger of sounding like (or being??) the sort of @___hole on Wikipedia that I really hate, I will stop in a moment. But what I suggest is this: it should go to the former wording where there are the two names, and the official name should simply be Holy Island. We should not use the formulation "Holy Island of Lindisfarne" unless a really credible official source can be found to support it. By this I mean government, mapping agencies, census or electoral bodies, stuff like that. Not a web manager whim or a marketing person looking for a nice phrase. I am not going to be stupid about this and argue against it if you find something that nails it and I promise that my approach to this would be honest – I would not mess you around. But it has to be solid, unassailable evidence. Notwithstanding all the points already made, if there really is an Official Name then surely it must must exist in an official source, easily findable and verifiable, no? Or am I going nuts? (Please don't answer that last point!) I'm sorry to sound like a bad-tempered old git about this and am trying to avoid it but it's getting my goat a bit: I think its use undermines our duty to stick with the facts and instead promotes a sort-of neologism, cuteism, marketing-speak, journalese etc.

 * What do you think? I would really like to change it as I believe that it would improve the article but I am loth (or loath!) to edit-war. I've rabbitted on more than enough. Best wishes to all, DBaK (talk) 13:04, 13 November 2021 (UTC)
 * I'll get back to you shortly. I've just done a major upgrade and have been a bit unwell over the w/e. Martin of Sheffield (talk) 07:55, 16 November 2021 (UTC)
 * Thanks and no rush! Hope you are better soon. Cheers DBaK (talk) 08:24, 16 November 2021 (UTC)
 * Hi and, I hate to nag but are we any further on with this please? Best wishes to all DBaK (talk) 19:48, 10 January 2022 (UTC)
 * My opinion isn't much changed: "Holy Island of Lindisfarne" is a silly and artificial name that doesn't belong in the article. Zacwill (talk) 20:29, 10 January 2022 (UTC)
 * I'm sorry Zacwill, but I do tend to think that Northumberland County Council's opinion is probably more WP:RS than yours however well held. Whether or not it is silly is another matter, but considering there are places in that area with names like "Pity Me" we really can't use silliness as a reason to exclude things!  You may not like official tourism sites like Visit England and Visit Northumberland, but they are official bodies backed by HMG and NCC respectively.  Given that we are talking about 8thC and 11thC recorded uses of both parts of the name it does become a little difficult to dismiss the terms as recentisms.  I think the opening sentence sets out the situation perfectly, giving it it's full name, and then the abbreviations, compare if you will "Kingston upon Hull, usually abbreviated to Hull, is a port city and unitary authority in the East Riding of Yorkshire, England".  Perversely, I'm not so sure about the infobox though.  Until you look closely the "of" in the first line is easily confused with the "or" in the second.  Still I appear to be outvoted on this though, so although I think it's wrong, misleading to the readers and a mistake, I'll not stand in the way of you changing things to your preference. Martin of Sheffield (talk) 22:19, 10 January 2022 (UTC)
 * (Disclaimer: I lived and worked in Durham for over 30 years, although moved away a dozen years ago.) Travelling up and down the A1(M) near Durham are road signs that say "Durham — Historic Cathedral City" and "County Durham — Land of the Prince Bishops".  Those wordings may be nice marketing-speak, but they are not formal titles, and wouldn't play a significant role in Wikipedia articles about the places or their environs.  "Holy Island of Lindisfarne" strikes me as being of comparable nature to such Durham signage.  Before, during and after my 30+ years in the Durham area, including church visits to Lindisfarne, I commonly came across (and used) the names "Lindisfarne" and "Holy Island".  But I'm struggling to remember ever encountering that lengthy construction "Holy Island of Lindisfarne".  My suggestion is that the principal name used in the article should be "Lindisfarne", with a reasonable tolerance for "Holy Island" if a particular context merits that, but that "Holy Island of Lindisfarne" should not play any significant role.  I would suggest that the opening words of the article should be something like "Lindisfarne or Holy Island (occasionally also referred to as The Holy Island of Lindisfarne)...". Feline Hymnic (talk) 23:43, 10 January 2022 (UTC)

thanks everyone. We don't seem to have moved much further and I retain my absolute, serious doubt that a tourist site, which exists for promotion and can be expected to use poetic and flowery language, is a reliable source, no matter who funds it. I promise, as I have promised, that if someone brings a proper reliable source for HIOL being some kind of official name then I will look carefully and respectfully at it but I have not, with the greatest respect, seen anything that faintly resemble this yet. And yes I have looked, really. We cannot any longer go on, without evidence, promoting the idea that HIOL is any sort of official name and the article already clearly remarks on its tourist and promotional usage, which is fine. I am going to edit it to something that I feel is reasonable, and take a bit of a step back for a while, for personal reasons. Best to all, DBaK (talk) 10:57, 20 January 2022 (UTC)

title: Talk:Lindisfarne


text: User:Poitypoity

title: User:Poitypoity


text:
User talk:Poitypoity

Hello and welcome! I've been enjoying reading your contributions to Wikipedia. Cheers! --mav

I'd like to echo mav's welcome :-) I moved your comment from Week to the discussion page Talk:Week, and incorporated some of it back into the article. -- Khendon

Wallace Stevens
Because you have edited the article, you are invited to participate in an Editors Poll on the Wallace Stevens discussion page. --Halcatalyst 18:23, 26 February 2006 (UTC)

title: User talk:Poitypoity


text:
User:Tengai~enwiki

My name is Stephan. I live in Frankfurt, Germany and work as a freelance software developer.

de:Benutzer:Tengai es:Usuario:Tengai

title: User:Tengai~enwiki


text:
Eleoncio Mercedes

Eleoncio Mercedes (September 12, 1957 – December 22, 1985) was a Dominican boxer, who was world champion in the Flyweight division.

Amateur career
As an amateur he competed for his native country at the 1976 Summer Olympics in Montreal, Quebec, Canada. He was stopped in the first round of his opening round bout to Aleksandr Tkachenko of the Soviet Union. Mercedes was the flag bearer for the Dominican Republic in the 1976 opening ceremony.

Pro career
Born in La Romana, Mercedes campaigned most of his career in the western United States and in Mexico. He debuted as a professional boxer on July 2 of 1978 with a win over Darryl Jones in Stockton. He suffered his first defeat when he lost by a decision in Las Vegas to future world champion Joey Olivo, in Mercedes' third bout as a paid fighter.

Mercedes' first of 11 fights in a row in Mexico came in 1979, when he lost by a knockout in seven rounds to Juan Díaz. During that span of 11 fights in Mexico, he went 6-3-2, fighting in such places as Mexico City, Monterrey and Reynosa. He lost to Candido Tellez but also beat former world champion Guty Espadas, by a knockout in nine during that span.

His first fight in the Dominican Republic was a 1982 rematch with Diaz, held in Santo Domingo. He won the fight by a decision in twelve rounds, to avenge his defeat at the hands of Diaz. Up until that moment, Mercedes' record was of 10 wins, 6 losses and 2 draws, reason why it was a little surprising to his fans when the WBC announced it would give Mercedes a chance at becoming a world champion, against two time world champion Freddie Castillo, who was in his second reign. The two boxers met on November 6 of 1982, at Los Angeles. Mercedes caused another surprise among many boxing fans by defeating Castillo by a decision in 15 rounds and becoming WBC and Lineal Flyweight champion.

In his first defense, Mercedes put the titles on the line against the British boxer Charlie Magri. In round seven, the fight had to be stopped because of a cut suffered by Mercedes, which had been determined to be from a punch by Magri. Mercedes then lost his world Flyweight championships by a technical knockout in that round.

After that, Mercedes kept on boxing, but had mixed fortunes. He managed to beat future world title challenger Alonzo Gonzalez by a decision, but lost to future world champion, Mexican German Torres by a knockout in the ninth round. Mercedes also lost a twelve-round decision to future world champion Raul Jibaro Perez, as well as being knocked out in the sixth round by former world Bantamweight champion Alberto Davila.

Death
A few days before Christmas in 1985, Mercedes was shot and killed by a policeman in his native La Romana, aged 28, after allegedly pulling a gun on the policeman. Mercedes had been drinking in a bar when he was shot to death. Confusion exists as to how this incident took place as some sources state the altercation happened after a car accident.

title: Eleoncio Mercedes


text:
Sigmund Freud Archives

The Sigmund Freud Archives mainly consist of a trove of documents housed at the US Library of Congress and in the former residence of Sigmund Freud during the last year of his life, at 20 Maresfield Gardens in northwest London. The archive comprises Freud's tapes, letters and papers. It was founded in 1951 by Kurt R. Eissler among others, and received contributions from Anna Freud.

It was at the center of a complicated scandal, described in Janet Malcolm's book In the Freud Archives and also covered by Jeffrey Masson in his book Final Analysis.

Early history
The Archives were founded by Kurt R. Eissler in 1951, together with a group of people who knew Freud personally, including Heinz Hartmann, Ernst Kris, Bertram Lewin and Hermann Nunberg. It was directed by Eissler for decades after its founding. Eissler prevented many well-meaning scholars from seeing many Freud documents claiming confidentiality, even when their donors had not requested nor demanded that confidentiality, nor was anyone a potential victim of the revelation of those documents. By the 1980s, Eissler, with the help of Anna Freud, had expanded the collection to include thousands of items.

Masson controversy
Eissler was introduced to Masson in 1974. Masson was appointed secretary, and Eissler intended for Masson to succeed him as director, which he did in 1980. Being an officer of the Archives, Masson had administrative access to all its documents, and he was therefore allowed to see anything he wanted breaking the seal whenever necessary.

In 1981, Masson published a paper wherein he claimed that Freud's abandonment of his seduction theory had taken place for reasons not related to the scientific merit of the theory, namely that Freud believed that granting the truth of his female patients' claims that they had been sexually abused would risk the reputation of the emerging psychoanalytic method. Masson said that "Freud began a trend away from the real world that, it seems to me, has come to a dead halt in the present-day sterility of psychoanalysis throughout the world."

Eissler was deeply shocked ("Just today Masud Khan called me from London and asked me to dismiss you from the Archives. The board members, all of them, or at least most of them, are asking for the same." ), and Masson was subsequently dismissed from his job at the Archives, whereupon followed bilateral legal action and a well-publicized scandal.

Recent history
Harold P. Blum succeeded Masson and Eissler as Executive Director. He was again succeeded by Louis Rose, who is the current director. The other current officers are Jennifer Stuart as President, Nellie L. Thompson as Secretary, and W. Craig Tomlinson as Treasurer.

Literature

 * Janet Malcolm: In the Freud Archives, New York, Knopf, 1984, ISBN 0-394-53869-2. Paperback edition, New York, Vintage Books, 1985, ISBN 0-394-72922-6. British edition, London, Papermac, 1997, ISBN 0-333-64471-9. New edition, with an afterword by the author, New York, New York Review Books, 2002, ISBN 1-59017-027-X.
 * Jeffrey Moussaieff Masson: The Assault on Truth: Freud’s Suppression of the Seduction Theory. New York, Farrar, Straus and Giroux, 1984, ISBN 0-374-10642-8.
 * Jeffrey Moussaieff Masson: Final Analysis: The Making and Unmaking of A Psychoanalyst. Reading, Massachusetts, Addison-Wesley, 1990, ISBN 0-201-52368-X. Paperback edition, New York, Ballantine Books, 2003, ISBN 0-345-45278-X, GTIN 9780345452788.

title: Sigmund Freud Archives


text:
Janet Malcolm

Janet Clara Malcolm (born Jana Klara Wienerová; July 8, 1934 – June 16, 2021) was an American writer, staff journalist at The New Yorker magazine, and collagist who fled antisemitic persecution in Nazi-occupied Prague. She was the author of Psychoanalysis: The Impossible Profession (1981), In the Freud Archives (1984), and The Journalist and the Murderer (1990). Malcolm wrote frequently about psychoanalysis and explored the relationship between journalist and subject. She was known for her prose style and for polarizing criticism of her profession, especially in her most contentious work, The Journalist and the Murderer, which has become a staple of journalism-school curricula.

Early life
Malcolm was born in Prague in 1934, one of two daughters (the other is the author Marie Winn), of Hanna (née Taussig) and Josef Wiener (aka Joseph A. Winn), a psychiatrist. She resided in New York City after her Jewish family emigrated from Czechoslovakia in 1939, fleeing Nazi persecution of Jews. Malcolm was educated at the High School of Music and Art, and then at the University of Michigan, where she wrote for the campus newspaper, The Michigan Daily, and the humor magazine, The Gargoyle, later editing The Gargoyle.

Career
Malcolm was a literary nonfiction writer known for her prose style and her examination of the relationship between journalist and subject. She began working at The New Yorker in 1963 with women's interest assignments, writing about holiday shopping and children's books, as well as a column on home decor. She next wrote about photography for the magazine. She moved to reporting in 1978, which Malcolm attributed to her smoking cessation in a 2011 profile by Katie Roiphe: "She began to do the dense, idiosyncratic writing she is now known for when she quit smoking in 1978: she couldn't write without cigarettes, so she began reporting a long New Yorker fact piece, on family therapy, called 'The One-Way Mirror.'" Her preference for writing in the first person was influenced by New Yorker colleague Joseph Mitchell, and she developed an interest in the construction of the auctorial subject as much as the objects it described, quickly realizing "this 'I' was a character, just like the other characters. It's a construct. And it's not the person who you are. There's a bit of you in it. But it's a creation. Somewhere I wrote, 'the distinction between the I of the writing and the I of your life is like Superman and Clark Kent.'" She turned this interest in the construction of narrative to a variety of subjects, including two books about couples (Gertrude Stein and Alice B. Toklas, and poets Sylvia Plath and Ted Hughes), one on Anton Chekhov, and the true crime genre, and particularly returned repeatedly to the subject of psychoanalysis.

Malcolm was elected to the American Academy of Arts and Letters in 2001. Her papers are held at the Beinecke Rare Book & Manuscript Library at Yale University, which acquired her archive in 2013.

Psychoanalysis: The Impossible Profession
In 1981, Malcolm published a book on the modern psychoanalytic profession, following a psychoanalyst she gave the pseudonym “Aaron Green”. Freud scholar Peter Gay wrote that Malcolm's "witty and wicked Psychoanalysis: The Impossible Profession has been praised by psychoanalysts (with justice) as a dependable introduction to analytic theory and technique. It has the rare advantage over more solemn texts of being funny as well as informative".

In his 1981 New York Times review, Joseph Edelson wrote that Psychoanalysis: The Impossible Profession "is an artful book", praising Malcolm’s "keen eye for the surfaces — clothing, speech and furniture — that express character and social role" (noting she was then the photography critic for The New Yorker). It succeeds because she has instructed herself so carefully in the technical literature. Above all, it succeeds because she has been able to engage Aaron Green in a simulacrum of the psychoanalytic encounter — he confessing to her, she (I suspect) to him, the two of them joined in an intricate minuet of revelation."

The book was a 1982 National Book Award for Nonfiction finalist.

In the Freud Archives and the Masson case
Articles Malcolm published in The New Yorker and in her subsequent book In The Freud Archives (1984) offered, according to the book's dust jacket, "the narrative of an unlikely, tragic/comic encounter among three men." They were psychoanalyst Kurt R. Eissler, psychoanalyst Jeffrey Moussaieff Masson, and independent Freud scholar Peter J. Swales. The book triggered a legal challenge by Masson, the former project director for the Sigmund Freud Archives. In his 1984 lawsuit, Masson claimed that Malcolm had libeled him by fabricating quotations she attributed to him.

In August 1989, United States Court of Appeals for the Ninth Circuit in San Francisco agreed with a lower court in dismissing a libel lawsuit that Masson had filed against Malcolm, The New Yorker and Alfred A. Knopf.

Malcolm claimed that Masson had called himself an "intellectual gigolo". She also claimed that he said he wanted to turn the Freud estate into a haven of "sex, women, and fun" and claimed that he was, "after Freud, the greatest analyst that ever lived." Malcolm was unable to produce all the disputed material on tape. The case was partially adjudicated before the Supreme Court, which held that the case could go forward for trial by jury.

After a decade of proceedings, a jury finally decided in Malcolm's favor on November 2, 1994 on the grounds that, whether or not the quotations were genuine, more evidence would be needed to rule against Malcolm.

In August 1995, Malcolm claimed to have discovered a misplaced notebook containing three of the disputed quotes, swearing "an affidavit under penalty of perjury that the notes were genuine."

The Journalist and the Murderer
Malcolm's 1990 book The Journalist and the Murderer begins with the thesis: "Every journalist who is not too stupid or too full of himself to notice what is going on knows that what he does is morally indefensible."

Her example was the popular nonfiction writer Joe McGinniss. While researching his true crime book Fatal Vision, McGinniss lived with the defense team of doctor Jeffrey MacDonald while MacDonald was on trial for the murders of his two daughters and pregnant wife. In Malcolm’s reporting, McGinniss quickly arrived at the conclusion that MacDonald was guilty, but feigned belief in his innocence to gain MacDonald’s trust and access to the story—ultimately being sued by MacDonald over the deception.

Malcolm's book created a sensation when in March 1989 it appeared in two parts in The New Yorker magazine. Roundly criticized upon first publication, the book is still controversial, although it has come to be regarded as a classic, routinely assigned to journalism students. It ranks ninety-seventh in The Modern Library's list of the twentieth century's "100 Best Works of Nonfiction". Douglas McCollum wrote in the Columbia Journalism Review, "In the decade after Malcolm's essay appeared, her once controversial theory became received wisdom."

Further books
In the posthumously published Still Pictures: On Photography and Memory, Malcolm writes autobiographical sketches, starting the chapters from family photographs.

Reception
Malcolm's penchant for controversial subjects and tendency to insert her views into the narrative brought her both admirers and critics. "Leaning heavily on the techniques of psychoanalysis, she probes not only actions and reactions but motivations and intent; she pursues literary analysis like a crime drama and courtroom battles like novels," wrote Cara Parks in The New Republic in April 2013. Parks praised Malcolm's "intensely intellectual style" as well as her "sharpness and creativity."

In Esquire, Tom Junod characterized Malcolm as "a self-hater whose work has managed to speak for the self-hatred (not to mention the class issues) of a profession that has designs on being 'one of the professions' but never will be." Junod found her to be devoid of "journalistic sympathy" and observed: "Very few journalists are more animated by malice than Janet Malcolm.” Junod himself, however, has been criticized for a number of journalistic duplicities, including a smirking piece in Esquire which outed the actor Kevin Spacey, as well as a similarly homophobic faux profile of the singer Michael Stipe.

Katie Roiphe summarized the tension between these polarized views, writing in 2011, "Malcolm's work, then, occupies that strange glittering territory between controversy and the establishment: she is both a grande dame of journalism, and still, somehow, its enfant terrible."

Charles Finch wrote in 2023 "it seems safe to say that the two most important long-form journalists this country produced in the second half of the last century were Joan Didion and Janet Malcolm."

Personal life
Malcolm met her first husband, Donald Malcolm, at the University of Michigan. After graduation, they moved to Washington, D.C., where Malcolm occasionally reviewed books for The New Republic before returning to New York. Donald reviewed books for The New Yorker in the 1950s and 1960s and served as a theater critic. They had a daughter, Anne, in 1963. Donald Malcolm died in 1975.

Malcolm's second husband was long-time New Yorker editor Gardner Botsford, a member of the family that had originally funded The New Yorker. The author of A Life of Privilege, Mostly: A Memoir, Botsford died at age 87 in September 2004.

Death
On June 16, 2021, Janet Malcolm died of lung cancer at the age of 86 at a Manhattan hospital.

Non-fiction

 * Reissued in 2002 with an afterword by Janet Malcolm by New York Review Books. ISBN 9781590170274
 * Reissued in 2002 with an afterword by Janet Malcolm by New York Review Books. ISBN 9781590170274

As editor

 * Chekhov, Anton (2018). The Lady with the Little Dog and Other Stories. Translated by Constance Garnett; selected, with a preface by Janet Malcolm. riverrun.
 * — (2020). The Duel and other stories. Translated by Constance Garnett; selected, with a preface by Janet Malcolm. riverrun.
 * — (2020). Ward No. 6 and other stories. Translated by Constance Garnett; selected, with a preface by Janet Malcolm. riverrun.

Awards and honors

 * 1982 - National Book Award for Nonfiction finalist for Psychoanlysis: The Impossible Profession
 * 2001 - election to the American Academy of Arts and Letters
 * 2008 - PEN/Jacqueline Bograd Weld Award for Biography, Two Lives: Gertrude and Alice
 * 2013 - National Book Critics Circle Award (Criticism) shortlist for Forty-One False Starts
 * 2017 - American Academy of Arts and Letters Gold Medal for Belles Lettres and Criticism

title: Janet Malcolm


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Chinese postman problem

[[File:Chinese_postman_problem.svg|thumb|upright=1.5|A worked example of an undirected Chinese postman problem: 1. Each street must be traversed at least once, starting and ending at the post office at A.

2. Four vertices with odd degree (orange) are found on its equivalent graph.

3. The pairing with the lowest total length is found.

4. After corresponding edges are added (red), the length of the Eulerian circuit is found.]] In graph theory, a branch of mathematics and computer science, Guan's route problem, the Chinese postman problem, postman tour or route inspection problem is to find a shortest closed path or circuit that visits every edge of an (connected) undirected graph at least once. When the graph has an Eulerian circuit (a closed walk that covers every edge once), that circuit is an optimal solution. Otherwise, the optimization problem is to find the smallest number of graph edges to duplicate (or the subset of edges with the minimum possible total weight) so that the resulting multigraph does have an Eulerian circuit. It can be solved in polynomial time, unlike the Travelling Salesman Problem which is NP-hard. It is different from the Travelling Salesman Problem in that the travelling salesman cannot repeat visited nodes.

The problem was originally studied by the Chinese mathematician Meigu Guan in 1960, whose Chinese paper was translated into English in 1962. The original name "Chinese postman problem" was coined in his honor; different sources credit the coinage either to Alan J. Goldman or Jack Edmonds, both of whom were at the U.S. National Bureau of Standards at the time.

A generalization is to choose any set T of evenly many vertices that are to be joined by an edge set in the graph whose odd-degree vertices are precisely those of T. Such a set is called a T-join. This problem, the T-join problem, is also solvable in polynomial time by the same approach that solves the postman problem.

Undirected solution and T-joins
The undirected route inspection problem can be solved in polynomial time by an algorithm based on the concept of a T-join. Let T be a set of vertices in a graph. An edge set J is called a T-join if the collection of vertices that have an odd number of incident edges in J is exactly the set T. A T-join exists whenever every connected component of the graph contains an even number of vertices in T. The T-join problem is to find a T-join with the minimum possible number of edges or the minimum possible total weight. For any T, a smallest T-join (when it exists) necessarily consists of $$\tfrac{1}{2}|T|$$ paths that join the vertices of T in pairs. The paths will be such that the total length or total weight of all of them is as small as possible. In an optimal solution, no two of these paths will share any edge, but they may have shared vertices. A minimum T-join can be obtained by constructing a complete graph on the vertices of T, with edges that represent shortest paths in the given input graph, and then finding a minimum weight perfect matching in this complete graph. The edges of this matching represent paths in the original graph, whose union forms the desired T-join. Both constructing the complete graph, and then finding a matching in it, can be done in O(n3) computational steps.

For the route inspection problem, T should be chosen as the set of all odd-degree vertices. By the assumptions of the problem, the whole graph is connected (otherwise no tour exists), and by the handshaking lemma it has an even number of odd vertices, so a T-join always exists. Doubling the edges of a T-join causes the given graph to become an Eulerian multigraph (a connected graph in which every vertex has even degree), from which it follows that it has an Euler tour, a tour that visits each edge of the multigraph exactly once. This tour will be an optimal solution to the route inspection problem.

Directed solution
On a directed graph, the same general ideas apply, but different techniques must be used. If the directed graph is Eulerian, one need only find an Euler cycle. If it is not, one must find T-joins, which in this case entails finding paths from vertices with an in-degree greater than their out-degree to those with an out-degree greater than their in-degree such that they would make in-degree of every vertex equal to its out-degree. This can be solved as an instance of the minimum-cost flow problem in which there is one unit of supply for every unit of excess in-degree, and one unit of demand for every unit of excess out-degree. As such it is solvable in O(|V|2|E|) time. A solution exists if and only if the given graph is strongly connected.

Applications
Various combinatorial problems have been reduced to the Chinese Postman Problem, including finding a maximum cut in a planar graph and a minimum-mean length circuit in an undirected graph.

Variants
A few variants of the Chinese Postman Problem have been studied and shown to be NP-complete.
 * The windy postman problem is a variant of the route inspection problem in which the input is an undirected graph, but where each edge may have a different cost for traversing it in one direction than for traversing it in the other direction. In contrast to the solutions for directed and undirected graphs, it is NP-complete.
 * The Mixed Chinese postman problem: for this problem, some of the edges may be directed and can therefore only be visited from one direction. When the problem calls for a minimal traversal of a digraph (or multidigraph) it is known as the "New York Street Sweeper problem."
 * The k-Chinese postman problem: find k cycles all starting at a designated location such that each edge is traversed by at least one cycle. The goal is to minimize the cost of the most expensive cycle.
 * The "Rural Postman Problem": solve the problem with some edges not required.

title: Chinese postman problem


text:
Talk:Nazi Party

Extended-confirmed-protected edit request on 12 April 2024
The emblem is wrong, it should be this one https://upload.wikimedia.org/wikipedia/commons/thumb/f/fc/NSDAP-Logo.svg/640px-NSDAP-Logo.svg.png Carulaa (talk) 15:43, 12 April 2024 (UTC)

Not done for now: please establish a consensus for this alteration before using the template. PianoDan (talk) 18:25, 12 April 2024 (UTC)

Add a link
The article mentions the article "Ein Nazi fährt nach Palästina" by name. As an article by this name now exists, it would make sense to link it.

The article is protected so I can't do it. Editor8778 (talk) 12:50, 24 May 2024 (UTC)
 * Already ✅  G M G  talk  14:54, 19 June 2024 (UTC)

Extended-confirmed-protected edit request on 12 June 2024
Make the "succeeded by" be None (similar to the DNVP page) ManU9827 (talk) 21:36, 12 June 2024 (UTC)
 * I don't think this makes sense. Political party succession can be controversial or unclear, so it's best to omit the parameter if there is no clear successor (indeed, what about the Socialist Reich Party..) plus the infobox is already too long (t · c)  buidhe  14:34, 19 June 2024 (UTC)

Extended-confirmed-protected edit request on 14 June 2024 I would like to add links to complex words
DarbieIsANerd (talk) 00:45, 14 June 2024 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. — Czello (music) 07:35, 14 June 2024 (UTC)

title: Talk:Nazi Party