Talk:Collapse of the World Trade Center/Archive 13

Good Article Status
I'm trying to get the article ready to nominate for GA by the end of the year. All suggestions, help, questions, etc. are welcome. I've started with the mechanics of the collapses, which are now well understood. The article should be able to confidently describe what happened.--Thomas B (talk) 20:16, 8 December 2009 (UTC)


 * Well, it should confidently present a description of what happened as evidenced by reliable sources. This includes presenting some points where information provided by reliable sources is not uniform, and it also includes giving due weight to notable descriptions that are considered fringe views according to reliable sources, while providing appropriate context for the reader where necessary. Cs32en  20:26, 8 December 2009 (UTC)


 * The conflicts that lie down that road are, to use an expression I redently learned from Joe Biden, "out of my pay grade". Where NIST or the relevant engineers (like Bazant) are unclear (or where we don't quite understand them), I think we should just remain silent. Fringe view should be left in the relevant sections and articles.--Thomas B (talk) 20:45, 8 December 2009 (UTC)


 * "Unclear" is not sufficient of course. If there are different accounts evidenced by reliable sources, we can present those accounts, and we can described them as different if reliable sources have reported that. (Maybe that's actually more relevant for the 9/11 Commission Report article rather than this one.) What the due weight (and due position within the article's structure) for a particular piece of information is would depend on the coverage it has received in reliable sources, and I just wanted to make a general statement, not a particular proposal about where to put any particular piece of information. Cs32en  20:56, 8 December 2009 (UTC)


 * All I'm saying is that the end result should leave the reader with a clear and accurate impression of what (received opinion thinks) happened. In so far as presenting conflicting accounts muddles the image of what happened, we should not present them. The conflicting account can be duly weighted as such in other sections of the article or even other articles. I agree that we should take this on a case-by-case basis. I hope we won't disagree too much. I'm sure we'll be able to keep it both civil and interesting.--Thomas B (talk) 21:05, 8 December 2009 (UTC)
 * It should be clear that at minimum there is dissent among as to what happened.Richard Gage on Omni TV Vancouver,Richard Gage on KMPH Fox 26 in Fresno, CA,Niels H. Harrit, Department of Chemistry, University of Copenhagen, Denmark appears on TV2 News Denmark.,9-11 Blueprint for Truth to Debut on Colorado Public Television,World Archetectual News,Richard Gage on New Zealand National Television,CBC's The Fifth Estate and Asia Digest.Omitting stuff that is relevant is not the way to go. Tony0937 (talk) 21:22, 8 December 2009 (UTC)
 * With regard to different information that can be found in reliable sources, I did not, or not exclusively, think of instances in which such sources report on the views of other people. There is also different information, presented in different reliable sources as facts, about the duration of the collapse of the towers, the causes of the collapse of 7 WTC (e.g. role of the debris from the towers, diesel generators), and other aspects. Cs32en  21:33, 8 December 2009 (UTC)
 * Maybe an example would help me to decide whether or not I agree. Is there something in the mechanics section right now that is asserted too confidently?--Thomas B (talk) 21:39, 8 December 2009 (UTC)
 * Can you add some more references to these sections (possibly just pointing to the respective questions in the NIST FAQ)? I'd probably cover more information from the Bazant papers, as well as from the Purdue study (from the paper that actually got through the review process and which differs somewhat from the initial press release from Purdue university). I'll probably look again at the issue on the week-end. Cs32en  21:59, 8 December 2009 (UTC)
 * I'm done for today. I'll have a look at the referencing tomorrow.--Thomas B (talk) 22:03, 8 December 2009 (UTC)
 * Basboll, I reverted your changes pending further review by arbcom enforcement...I suggest you make all suggestions for relevent changes here before doing anymore editing. I will ensure you I will be polite and do what I can to work with you, however, your topic ban has not been fully discussed yet.--MONGO 03:30, 9 December 2009 (UTC)
 * Hi Mongo. That's cool. i'll check back in a couple of days.--Thomas B (talk) 04:57, 9 December 2009 (UTC)
 * Is it that Thomas B should discuss any non-trivial changes to the article while his ban is suspended, while other editors do not need to discuss such changes? My understanding of the suspension would be that Thomas B can edit the article in the same way as other editors while his ban is suspended. If my assumption is wrong, please let me know about the relevant policy or arbitration. Cs32en  14:06, 9 December 2009 (UTC)

Suggested section on the mechanics of collapse
Yesterday, I made a number of edits that MONGO has now reverted pending discussion of their merits. The section I'm suggesting looks like this. It is intended to replace the current "Collapse mechanism" section. As I said above, I see this as one step towards getting the article into GA shape. There hasn't been much progress on that front in my absence as far as I can tell. I'll stay out of the discussion for a couple of days to see whether the suspension of my ban is upheld. Until then, any comments on the merits and demerits of my proposal are welcome.--Thomas B (talk) 07:15, 9 December 2009 (UTC)

I'd like to know from MONGO why he has reverted the changes to the article that have been made recently. I haven't actually looked at them in detail, so I actually can't comment on the content at this moment. It would, however, contribute to a productive discussion if every editor communicates the reasons and rationales for his or her edits to the community of editors that are working on this article. Cs32en 14:01, 9 December 2009 (UTC) Addition: Seeing the discussion in the section above, the reason for the revert may actually have nothing to do with the content, but with Thomas B's status as an editor. If this is the case, you may ignore my question here, and we can keep the discussion on this particular issue in the section above. Cs32en 14:08, 9 December 2009 (UTC)

NIST quote
As neither NIST, nor any reliable source (to my knowledge), has highlighted the following quote from the section Collapse of the World Trade Center in any way, I suggest replacing the cquote template with the usual quote template. (My edit to this effect has been reverted.)

At this point, the core of WTC 1 could be imagined to be in three sections. There was a bottom section below the impact floors that could be thought of as a strong, rigid box, structurally undamaged and at almost normal temperature. There was a top section above the impact and fire floors that was also a heavy, rigid box. In the middle was the third section, damaged by the aircraft and weakened by heat from the fires. The core of the top section tried to move downward, but was held up by the hat truss. The hat truss, in turn redistributed the load to the perimeter columns. (p. 29)

Cs32en 14:29, 9 December 2009 (UTC)


 * I noticed that too while editing it, and ultimately decided that it shouldn't be a quote at all. A paraphrase works much better.--Thomas B (talk) 20:00, 9 December 2009 (UTC)

Mechanics of the collapses (Twin Towers) -- draft section
(Here's my current suggestion for a section to replace "Collapse mechanism")

Both buildings collapsed symmetrically and more or less straight down, though there was some tilting of the tops of the towers and a significant amount of fallout to the sides. In both cases, the portion of the building that had been damaged by the airplanes failed, which allowed the section above the airplane impacts to fall onto the undamaged structure below. As the collapse progressed, dust and debris could be seen shooting out of the windows several floors below the advancing destruction. The first fragments of the outer walls of the collapsed North Tower struck the ground 9 seconds after the collapse started, and parts of the South Tower after 11 seconds. The lower portions of both buildings' cores (60 stories of WTC 1 and 40 stories of WTC 2) remained standing for up to 25 seconds after the start of the initial collapse before they too collapsed.

Despite being undamaged under the impact area, the towers collapsed at near free fall speeds. While they were designed to support enormous static loads, they provided little resistance to the moving mass of the sections above the floors where the collapses initiated. Structural systems respond very differently to static and dynamic loads, and since the motion of the falling portion began as a free fall through the height of at least one story (roughly three meters) the structure beneath them was unable to stop the collapses once they began. Indeed, a fall of only half a meter would have been enough to release the necessary energy to begin an unstoppable collapse.

Collapse initiation
After the planes hit the buildings, but before they collapsed, the cores of both towers essentially consisted of three distinct sections. Above and below the impact floors, the cores consisted of what were essentially two rigid boxes; the steel in these sections was undamaged and had undergone no significant heating. The section between them, however, had sustained significant damage and, though they were not hot enough to melt it, the fires were weakening the structural steel. As a result, the core columns were slowly being crushed, sustaining plastic and creep deformation from the weight of higher floors. As the top section tried to move downward, however, the hat truss redistributed the load to the perimeter columns. Meanwhile, the perimeter columns and floors were also being weakened by the heat of the fires and as the floors began to sag they pulled the exterior walls inwards. In the case of 2 WTC, this caused the eastern face to buckle, transferring its loads back to the failing core through the hat truss and initiating the collapse. The section above the impact area then tilted in the direction of the failed wall. In the case of 1 WTC, the south wall later buckled in the same way, and with similar consequences.

Total progressive collapse
The collapse of the World Trade Center has been called "the most infamous paradigm" of progressive collapse. In the case of both towers, the top section tilted towards the face that had buckled, behaving largely as a solid block separate from the rest of the building. It fell at least one story in freefall and impacted the lower sections with a force equivalent to over thirty times its own weight. This was sufficient to buckle the columns of the story immediately below it and the block then fell freely through the distance of another story. Total collapse was now unavoidable as the process repeated through the entire height of the lower sections. The force of each impact was also much greater than the horizontal momentum of the section, which kept the tilt from increasing significantly before the falling section reached the ground. It remained intact throughout the collapse with its centre of gravity within the building's footprint. After crushing the lower section of the building, it was itself crushed when it hit the ground.

Crushing and pulverization
"It remained intact throughout the collapse with its centre of gravity within the building's footprint. After crushing the lower section of the building, it pulverised on impact with the ground." Can you indicate where this assertion is described in the source? I'm not finding any text in the source which appears to convey this meaning. Wildbear (talk) 10:21, 11 December 2009 (UTC)
 * That may be a somewhat too dramatic way of describing the "crush up" phase of the collapses. (I've fixed it now.) See page 309 of Bazant and Verdure's paper. Which reminds me: we need to find out if we can use Bazant's diagrams here and (I was also thinking) putting them together as an animation. If copyright requires that we redraw them, so be it. It could be a nice touch.--Thomas B (talk) 10:30, 11 December 2009 (UTC)
 * I'm looking at page 309. Let's consider it point by point:
 * "It remained intact throughout the collapse..." I don't see any wording stating this.
 * "...with its centre of gravity within the building's footprint" I don't see any wording stating this.
 * "After crushing the lower section of the building, it was itself crushed when it hit the ground." I don't see any wording stating this.
 * I realize that there is a diagram on the page which could be interpreted to be implying these assertions; but in my opinion, I don't think that we should be writing text based on our own interpretations of minimally-described diagrams. Wildbear (talk) 06:19, 12 December 2009 (UTC)


 * On page 313, Bazant and Verdure explain why there was no "crush-up" until the falling block reached the bottom. But before we get into too many details about sourcing this to particular pages of the article, do we agree that the sentence describes the process that B&V claim destroyed the towers? B&V do imagine (1) an intact falling block, (2) that does not "fall over like tree", (3) and which is ultimately "crushed-up". Don't they? If not, what do you propose to write instead?--Thomas B (talk) 07:27, 12 December 2009 (UTC)


 * As all the maths that Bazant and Verdure presents is based on the assumptions above, I think we can actually summarize this part of the article in that way, even if Bazant and Verdure do not use the same wording. Bazant and Verdure of course fail to explain why the (stronger) lower section is being completely destroyed, while the (weaker) upper section would remain intact until it hits the ground, but that's another matter. Cs32en  18:58, 12 December 2009 (UTC)

Bazant articles
Are there other researchers that have come to the same or similar conclusions with regard to the crush-down/crush-up hypothesis? Alternatively, has the crush-down/crush-up hypothesis been reported (without attribution) by reliable news media? If not, I think it would be better to have an inline citation for Bazant et al. Cs32en  02:10, 12 December 2009 (UTC)
 * I agree. It is not appropriate to state something as fact and then attribute it to one publication by one department of one university. The article needs to state that this is one researcher's explanation of the mechanism. That is the neutral position. -Jordgette (talk) 04:04, 12 December 2009 (UTC)
 * If there are a number of reliable news sources (i.e. not sources like Popular Mechanics, which has made itself a party to the case and is thus not an independent news media in that respect) that have reported these details as fact, we might not need an inline citation. My initial assumption, bases on what I remember reading in the media, is that this is not the case, or only for some of Bazants hypotheses. But we may need to check this before deciding how to present the issue. Cs32en  04:43, 12 December 2009 (UTC)
 * There's also Keith Seffen's paper.. I don't think we should describe this process at the level of the popular media. Even those who disagree (like Cherepanov) describe Bazant's account as the received view.--Thomas B (talk) 07:52, 12 December 2009 (UTC)
 * I may not quite be understanding Cs32en's concern here. I'd like to be able to use Bazant and Verdure, and perhaps Keith Seffen, and not the unpublished "What did and did not cause it?" paper (note 2 here in the draft). But I've started with the sources that are already in the article.--Thomas B (talk) 14:09, 12 December 2009 (UTC)
 * Of course the Bazant papers are valid sources. We do not need a news media report to use them. The question, in my view, is whether we should use an inline quotation or not. Cs32en  18:27, 12 December 2009 (UTC)
 * There is a more important issue here. The whole crush-down/crush-up is just a quirk of Bazant's mathematical model of the collapse, which is in itself a simplification of the real thing. The building probably didn't behave like that, and certainly the observable part didn't, being a significant visible crush-up concurrent with the crush-down. The paper should not be interpreted to mean that the crush-down then crush-up is what actually happened, and if carefully read it's quite clear that that's not what the author intended, but just a result of his simplified model. I started this discussion on the subject: . That affects the whole "Total progressive collapse" subsection, and particularly the last sentences describing the crush-down/crush-up. --pgimeno (talk) 00:37, 14 September 2010 (UTC)
 * Sorry, that was just destructive with no constructive proposal to replace it with. The only description of the collapse progression is FEMA's (sections 2.2.1.5 and 2.2.2.6 of FEMA Report 403 chapter 2, pp. 2-27 and 2-35 respectively). I guess that's what the contents of that section should reflect. Note that NIST dismissed FEMA's collapse initiation mechanism, not their collapse progression mechanism. --pgimeno (talk) 00:59, 14 September 2010 (UTC)

The Collapse initiation section
Everything in this section is stated as fact implying by default that supporting evidence was found. NIST stated that these claims are all assumtions to explain the collapse. They couldn't find any evidence for the extent of the column damage, nor could they find evidence for the steel deformation because there was not enough WTC steel saved to test this theory. Bazant's paper also not only mentions that computer simulations of the steel failure were not carried out by NIST because they would be (too) tedious and demanding but states that arguing the temperature of the fire and it's effect on the steel is a waste of time without it. Shouldn't the section explain this rather than excluding it? Wayne (talk) 16:39, 12 December 2009 (UTC)


 * My view is that this is "what is known" about the collapses. There are some who aren't sure that this is how it happened, but the relevant community of expert "knowers" (i.e., scientists) think this is what happened. Knowledge is not always based on evidence (though you and I may agree that it should be). It is supported by a paradigm that guides the work of scientific communities. In the middle ages they "knew" how many angels could dance on the head of a pin. Today, we're not even sure what they meant. But back then there wasn't much doubt about what the encyclopedia was supposed to say about it. The same is true here. It is easy to distinguish between the dominant engineering consensus and "alternative hypotheses" (as NIST puts it). While I think it would muddle this section, what you are suggesting here might be very informative in the section on the investigations (where the evidential basis of our knowledge of the collapses should be summarized. In fact, we could no doubt write a whole separate article on the investigation of the collapse of the world trade center. I'm game if you are. It would be a pleasure working with you on it.--Thomas B (talk) 17:44, 12 December 2009 (UTC)


 * I think this is not about arguing whether Bazant or NIST are correct or not. It is about how they presented their findings. There would be a difference between "The sequence was a follows: ..." and "Given the following assumptions, the most likely sequence was ...". We may have to look a the whole text to determine how the findings have been presented, as such qualifications are usually not included in every single sentence. It may well be the case that there are some statement that a being made in an absolute way, while some other statements are made with qualifications. Cs32en  18:32, 12 December 2009 (UTC)


 * Nothing is absolute. All knowledge is relative to assumptions. But encyclopedia articles make those assumptions, they do not have to state them. Those who know about these things (though not necessarily everyone who thinks seriously about them) makes the assumptions. We are given their assumptions. An encyclopedia represents what is known, not every complexity of how it came to be known, or how well it is known.--Thomas B (talk) 18:46, 12 December 2009 (UTC)


 * If a reliable source contains the statement "If A is true, then B must be true," then we cannot simply write "B is true," because this is not verifiable. We need to present relative knowledge as relative, not absolute, knowledge. Cs32en  19:20, 12 December 2009 (UTC)


 * But I assume we agree that, in this case, the same source assumes A to be true. More importantly, it claims that B is true. So we can report B on the basis of the source. Neither NIST nor Bazant were trying to explain how the WTC might have collapsed. They were trying to explain how it did collapse. They did not say that they failed in their attempt, nor that their conclusions are in any way tentative or speculative.--Thomas B (talk) 19:37, 12 December 2009 (UTC)


 * From reading Bazant and NIST, I understand they are saying that this is the most likely/plausable scenario. Bazant in particular provides mathmatics to support the possibility while NIST is rather vague. My concern is that we don't want to atract the "you are covering it up" crowd as reading the sources makes it clear they are not stating known facts but working backward from the end result. If the claim here goes beyond the sources then it makes no difference if the claim has a 99% probability, we discredit it ourselves. Cs32en has the right idea. We can't say B is true but we can say it has the highest probability and it's elements are supported by experimentation/mathematics. We just need to work on the language used. Wayne (talk) 20:48, 12 December 2009 (UTC)


 * A long time ago, FEMA openly declared their explanation for WTC7 to have a very low probability. That was important to mention along with their explanation. But now that the explainers are not qualifying their conclusions like that, we don't have to either. Think of this way: if use wording to the effect that this is the "most likely" explanation, it has be because there is some alternative that has a significant probability of being true. So it would be worth mentioning also. But we will not, in this section, mention any other hypothesis, right? So saying "most people think" or "the most likely explanation is" introduces an ambiguity (raises a question) that we do not resolve (because we will not answer the relevant question). That will make the section more difficult to understand, without making it more informative. I still think these concerns are best presented in the section on the investigations themselves. There, the fact that they worked backwards and had little physical evidence is relevant.--Thomas B (talk) 20:58, 12 December 2009 (UTC)


 * I've just looked at the Bazant/Verdure text again. While they say that they are using a number of simplifacation, they are also stating that the basic sequence would not change if these simplifications would not be made. I could give examples for qualified statements from NIST, but they do not involve the crush down/crush up scenario. I have made a general point about how we present statements made by sources, and while I firmly believe that this point is correct, it is probably not applicable to this particular Bazant/Verdure text with respect to the statements that we are reporting (or discussing about). Cs32en  00:41, 13 December 2009 (UTC)

A Clarification
I appreciate the comments people are making. There's a lot more that could be done. But keep in mind that I'm proposing this section to replace something that's already in the article. So the question is whether this is an improvement, not whether it's right in every way. If you have a simple way of making it even better, that will also be appreciated. Just remember that I'm suggesting a change to what the article is already saying (on the basis of sources that are already in there); I'm not suggesting the addition of something completely new.--Thomas B (talk) 17:49, 12 December 2009 (UTC)
 * If a proposal is an improvement with regard to the existing text, I wouldn't revert it, of course. But instead of changing the text, and then starting a discussion on how to further improve it, it seemed quite logical to discuss how your proposal can be further improved. So I do not interpret the comments as statements of preference with regard to the proposal and the existing text. Cs32en  00:45, 13 December 2009 (UTC)

Implementing
I've gone ahead and implemented the section. We can continue to discuss ways to improve it.--Thomas B (talk) 22:14, 13 December 2009 (UTC)

Thermite?
I don't think this article is going to pass GA with that sentence about thermite in there. The source is not RS (for this article), I suspect; and it doesn't really seem to fit in the section (the reader is not able to gauge its significance.) This blip in the development of the CD theory is covered nicely in the other article, where NIST's response is also noted. I don't think there's any need to mention it here (if there were, there are many other details that should be mentioned first, and I don't think we want to start down that road.) The issue seems pretty simple to me: CDers have published a paper that would be evidence for (though not proof of) CD if there was no doubt about the sample; NIST, however, has cast doubt on the authenticity of the sample. End of story. It's a story worth telling in the article about CD, but not in the article about the collapses, where all we need to say is that the CD theory exists and NIST rejects it. What do the rest of you think?--Thomas B (talk) 14:51, 14 December 2009 (UTC)


 * I agree the sentence should be removed. This article shouldn't be doing anything more than noting that the conspiracy theories exist, that they are rejected and pointing the reader towards a sub-article if they want to find out more. Problems with the paper are not limited to the sample, I've seen plenty of questions raised regarding the journal and the content of the paper.
 * Thermite theories have been discussed on this page previously and were removed, this version seems to have been added a month ago without any discussion. Hut 8.5 15:50, 14 December 2009 (UTC)


 * The paragraph on "CD theories" should be a brief summary of the sub-article, which it is not, at the moment. It does not inform the reader about the theories, but about polls related to the theories. This is followed by an information about NIST's position, which is in turn followed by one aspect of these theories. The thermite should be mentioned briefly in a sentence that says something like "different methods for the alleged destruction of the building by controlled demolition have been proposed, such as the use of thermite or super-thermite". We need to take the lead of the sub-article as the starting point for rewriting that whole section. CBC's The Fifth Estate has recently covered the thermite issue (as well as Danish TV stations some time ago), so the availability of reliable sources with regard to the claim ("scientists have published a paper claiming that...") is not a problem. Cs32en  20:14, 14 December 2009 (UTC)


 * The issue is normally weight. If this section becomes too detailed, it may been seen as advocacy for CD rather than information about it. The CD article is very informative right now; a link and a one- or two-sentence summary is quite sufficient (anyone who is interested is just a click away from more information). That solution has the virtue of being stable. Anything more has a tendency to turn the section into a site of much conflict. That said, we can obviously discuss what those two sentences should say. My view is that Harritt's thermite study is an important recent development within the theory but is not yet part of its outward characteristics. (That is: it is of interest to those pursuing the theory but is too esoteric for those who want to know about the "conspiracy theorists".)--Thomas B (talk) 20:36, 14 December 2009 (UTC)


 * Wikipedia strives to be a serious encyclopedia. As such, including fringe theories on such a serious topic where thousands of people died is unwarraranted.  We should remove the paragraph.  Actually, it never should have been added in the first place.  A Quest For Knowledge (talk) 23:57, 14 December 2009 (UTC)
 * I would suggest reading Shyam Sunder's opening statement at at August 21, 2008 press briefing for the relase of the draft report on WTC7. NIST has long taken CD seriously enough to explicitly dismiss it. It has long been possible to source the statement that WTC was not brought down by controlled demolition to NIST. In this briefing, however, Sunder goes even further. He found it necessary to begin his remarks with the dismissal (and the web page even sets the relevant statements in bold type). However we may feel about the theory, we cannot ignore it. Many readers of this article will have come to WP as part of their attempt to assess the conspiracy theories. We can help them by providing NIST's explicitly stated position.--Thomas B (talk) 05:22, 15 December 2009 (UTC)


 * While the information about the Jones/Harrit publication may be too detailed here, the thermite/super-thermite hypothesis has been around before, and has been reported on by multiple reliable sources (much more than have reported on the super-thermite paper). What we need in this article here is not specific information, with each item sourced to a particular news report, but a short overview of what is contained in the CD article. Cs32en  02:23, 15 December 2009 (UTC)


 * I agree with that in principle. Though I will be emphasizing brevity over providing an overview. I'm going to remove the thermite sentence now. We can then begin to discuss are more adequate section on CD.--Thomas B (talk) 05:25, 15 December 2009 (UTC)

Core structure: what's it made of?

 * NIST NCSTAR 1-6: "The collapse analyses of the WTC towers concentrated on modeling failure mechanisms in steel rather than concrete components, since the WTC towers were essentially steel structures; concrete was used only for the floor slabs." (ref)
 * MSNBC: "Still, (Leslie E.) Robertson, whose firm is responsible for three of the six tallest buildings in the world, feels a sense of pride that the massive towers, supported by a steel-tube exoskeleton and a reinforced concrete core, held up as well as they did—managing to stand for over an hour despite direct hits from two massive commercial jetliners." (ref)
 * Century Dynamics Incorporated, X. Quan and N. K. Birnbaum: "The core columns were made of steel-reinforced concrete material and had a cross-sectional area of 0.2 square meters. They were almost uniformly spread throughout the entire central core.  Besides the core columns, the central core also had a core wall made of the steel-reinforced concrete to separate it from the office area of the building." (ref)
 * BBC: "The protective concrete cladding on the cores would have been no permanent defence in these extraordinary circumstances - keeping the intense heat at bay for only a limited timespan." (ref)

It seems a bit awkward to have the article describing the structures as having a "rectangular tubular concrete core" in direct contradiction to NIST's assertion that "concrete was used only for the floor slabs", given that much of the collapse analysis presented is based upon the findings of NIST. In the few hours that I spent looking, I didn't find a reliable source which appeared to present a resolution for the discrepancy. Wildbear (talk) 08:59, 16 December 2009 (UTC)


 * My understanding is that there was no concrete in the structural system of the tower. Concrete was only used in the floor slabs (as NIST says). I'll try to track down that Finniston book. But "illustrated histories" of broad subjects make mistakes on points of detail. In this case, the book could be right about modern skyscrapers in general but wrong about WTC. NIST certainly did not explain how a concrete core was weakened to the point of collapse. The Bazant & Zhou mechanism also only applies to steel box columns with no concrete. I think we should resolve this in favour of the structure NIST described in 2006, not the structure Sir Monty Finniston signed off on in 1992.--Thomas B (talk) 13:29, 16 December 2009 (UTC)


 * (edit conflict) I think the phrase "concrete was used only for the floor slabs" refers to NIST's model of the towers and not the towers themselves. The same page of NCSTAR 1-6 says "Normal weight concrete...was used in the core and mechanical floors", which implies concrete was indeed used in the core. Hut 8.5 13:34, 16 December 2009 (UTC)


 * I think it means that concrete was used in the floors within the core, but lighter concrete was used for tenant spaces ((also in the floors only). The article seems now to say the core structural design included concrete, but NIST says quite clearly that it didn't.--Thomas B (talk) 14:16, 16 December 2009 (UTC)


 * The core included concrete to increase stiffness, as the main force that the structure had to cope with was not gravity, but angular momentum due to wind. Although not its main purpose, the concrete also helped carrying the weight of the building. I think that several websites picked that up, and got the information from reliable sources. I'm going to check this in the next few days, so I'd suggest to leave the sentence in the article, for the time being. (I wouldn't object to taking it out in the meantime, though, and to reinsert some well-sourced information later on.) Cs32en  14:39, 16 December 2009 (UTC)


 * Yes, I think the concrete in the floors did provide lateral support and was, in that sense, load-bearing. But I don't think there was any concrete in the columns (or that any of the concrete in the walls was load-bearing). But, yes, let's see what the sources say. I would prefer we remove the sentence in the meantime.--Thomas B (talk) 16:19, 16 December 2009 (UTC)

BTW, that MSNBC article is wrong. Robertson did not become a partner in the company until 1973. He was contracted by the company in 1966 to design part of the WTC which was the first high rise he had ever worked on. He had nothing to do with the design in regards to structual strength. He was involved in the sway reduction design elements. Wayne (talk) 19:25, 16 December 2009 (UTC)
 * The confusion may have come about because the concrete, which was only on the floor, was irrelevant to the structural strength. All the steel columns were exposed, on the perimeter they were encased by design features and in the core they were all in a maintenance space. The maintenance space walls may have been concrete but they did not encase the columns. The engineers designed the buildings to exceed the required building codes. For example the WTC was only required to support 5X the static load and withstand 3X the possible dynamic load. The WTC steel core was designed to support 16X the static load and withstand 10X the dynamic load. Additionally the perimeter columns were designed to support 200X their static load. Essentially the architects did not consider the concrete because there was no need and this is supported by their statements in 1965 when the building was critisized for being structurally weak due to the open spaces on the floors.


 * Heres a copy of the floor plan blueprints showing the core. You can only find them on conspiracy websites (they were leaked in 2007) as NIST prohibits public access to them so you have to judge reliability yourselves. Heres some notes I made some time ago: The buildings had a steel reinforced, cast concrete interior "tube" surrounded by a structural steel framework. The concrete core was formed in four rectangular shear wall cells that had smaller box columns inside them, mostly in internal rooms. The cells also contained hallways, toilets, elevators and stairways inside them. This is called "tube in a tube" construction. The box columns were fastened to the outside of the concrete core by 3 inch thick steel bars. This connection between the box columns and the concrete made the core a load bearing and anti torsion element for the steel framework but was not considered for structural strength as it already far exceeded code. The box columns on the north side were in a 3x7 foot access hallway. The others were exposed and clad in gyprock. Wayne (talk) 20:10, 16 December 2009 (UTC)


 * I made a mistake so am correcting it to avoid it looking like a CT lol. It was the Port Authority that prohibits public access, not NIST. The PA is worried about being sued if the plans show something wrong. They "loaned" the blueprints to NIST for the investigation but NIST can't release them or even describe what they say without PA permission. Wayne (talk) 20:24, 16 December 2009 (UTC)


 * I didn't know about this issue. I'll have a look at Hoffman's page some more. He doesn't empasize the presence of concrete as a discrepancy between NIST and the leaked documents as far as I can tell. In any case, it looks like it will be difficult to describe the core as made of concrete based on reliable sources if NIST doesn't allow the public to seem them.--Thomas B (talk) 20:24, 16 December 2009 (UTC)


 * You hit the nail on the head. All sources including NIST are basically presenting WP:OR until the blueprints enter the public domain (leaked documents can't be RS). For example NIST has been critisized for not making public the column dimensions and using diagrams that misrepresent them. Some claim it is part of the conspiracy but I assume NIST can't make such data clear without leaving itself open to litigation because NIST was never given the powers investigating bodies normally have (ie:no subpoena powers etc) to enable an unrestricted investigation. There should be some books on architecture that give simplified descriptions of the core. Wayne (talk) 15:50, 17 December 2009 (UTC)


 * WP:OR does not really apply to our sources. (Maybe I've misunderstood you: surely NIST is RS, and leaked blueprints not.) NIST (legitimately) did the OR, it's we (wee) Wikipedians that aren't allowed to introduce our own OR into the articles. I think the litigation issue may well be right. It can go in the description of the investigations (in some form). The NYT's coverage is, within bounds, actually quite critical of how the collapse investigations were handled.--Thomas B (talk) 19:44, 17 December 2009 (UTC)

30yearconspiracy's edits
I'm not quite sure what you're up to, 30yearconspiracy. The links you are replacing were just fine. And the concrete core stuff is being discussed. (I've also left a comment on you're talk page.) Can you explain your edits please?--Thomas B (talk) 19:34, 16 December 2009 (UTC)

I am very new to wiki and do not understand this environment for explanation. I am also a witness to the construction by viewing a documentary in 1990 and can evidence every edit with facts. This environment is very new to me and I thought I just did explain my edits now I have no idea of where the explanations have gone. 30yearconspiracy (talk) 19:47, 16 December 2009 (UTC)
 * You don't look like a new editor to me...you seem to have an indepth understanding of formating refs...--MONGO 02:51, 17 December 2009 (UTC)

The aspect of references of what is thought to be authority on the structure must be tested by images from 9-11 because of the PBS documentary I viewed, "The Engineering and Construction of the Twin Towers". Also the ex NYC mayor took all of the official documents from city offices which contained the only other set of plans other than that in the towers. http://web.archive.org/web/20020224015919/http://www.nyclu.org/g_archive020602.html The PBS digital archives have been purged but other paper PBS records show it. Dr. Ron Larsen and a former Marine Major, Drew Malone Raines III conducted a very thorough search and found evidence of it listed in libraries. A copy was found but copy of that was intercepted repeatedly. Dr. Larsen had a web radio show and updated that search in 2007, excerpt of it is here in an .mp3. http://algoxy.com/psych/audio/rl-cb6-27-07pbs.doc_1-2.mp3 30yearconspiracy (talk) 20:02, 16 December 2009 (UTC)


 * Welcome to Wikipedia. Just to make sure we don't talk past each other: you are arguing that the cores were built out of concrete, right? (And you understand that this contradicts the NIST report's

If what I have until now thought about the tower is true then the account in Finniston's encyclopedia would have to be an error. It wouldn't surprise me to find such a mistake in an encyclopedia of that kind, but I don't think we can just discount it. I've been looking around on the web and it looks the description of the core as made of concrete is mainly found on conspiracy theory sites of one kind or another. That doesn't settle it one way or the other for me. The Domel report doesn't provide any sources (and doesn't seem to mention any contact with FEMA). Nor did FEMA (I think) have access to plans of the WTC in the days immediately after 9/11.--Thomas B (talk) 21:20, 16 December 2009 (UTC)

I know NIST is wrong, mislead. No point in my reading it. Without the plans which were in the WTC documents from NYC they cannot possibly conduct a forensic investigation of collapse. Conspiracys exist. My username at wiki comes from Senator Bob Kerreys statement on November 28 recorded on video as seen on youtube, http://www.youtube.com/watch?v=gtJWBcWAeAw where he identified 9-11 as a 30year conspiracy. Elsewhere in the Domels safety report it states that consults with FEMA were his basis for stating the concrete core. We have 2 other written sources, one the engineer himself. All images from 9-11 confirm the concrete core shear walls and disprove the presence of any steel core columns inside the core whatsoever. 30yearconspiracy (talk) 21:29, 16 December 2009 (UTC)


 * Well, we can't really write the section on the structural design section in a manner that contradicts the section on how the structures collapsed. So we have to resolve it without simply dismissing the NIST report as irrelevant. The standing consensus on this article is that the conspiracy theories are wrong, not NIST. You might say the article is supposed to state the "official account" of the collapses as accurately as possible.--Thomas B (talk) 21:54, 16 December 2009 (UTC)
 * Thomas...no, of course we're not going to dismiss the NIST study as irrelevant...and there is nothing to resolve...no one has yet come forward with a more agreed to scientific understanding of how the structures collapsed...I really like this strawman approach...lets have someone come along and try and propose both ludicrous and preposterous references and edits so you can show your new found dedication to NPOV by arguing with the strawman...heh.--MONGO 03:10, 17 December 2009 (UTC)

No simple dismissal is intended. The term "conspiracy theories" is a generalization which is a cognitive distortion. Shall such distortions guide the Wikipedia intent to provide facts? There is independently verified evidence that the core structure was a rectangular concrete tube. No such documentations exist for the steel core columns. It all leads back to FEMA and the NDA's signed by NIST regarding the plans from the port authority are not evidence for steel core columns in the core area. "I made a mistake so am correcting it to avoid it looking like a CT lol. It was the Port Authority that prohibits public access, not NIST. The PA is worried about being sued if the plans show something wrong. They "loaned" the blueprints to NIST for the investigation but NIST can't release them or even describe what they say with PA permission. Wayne (talk) 20:24, 16 December 2009 (UTC)" BTW, there are some serious questions raised about the plans at http://911research.wtc7.net/wtc/evidence/plans/frames.html. I've confirmed what was found in the revision tables that appear as digital alterations of the scanned plans. No hardcopy was ever provided by Silverstein and associates who provided the scans to Steven Jones the BYU conspiracy theorist. The plans at wtc7.net are from materially interested sources not official. As posted, Senator Bob Kerreys statement on November 28 recorded on video as seen on youtube, http://www.youtube.com/watch?v=gtJWBcWAeAw where he identified 9-11 as a 30year conspiracy. Accordingly, from an official source, it is shown that a 30 year conspiracy exists meaning that there is justification for question of "official information". Senator Kerrey is an ex Navy seal and does not look happy with stating what he does. Should the peoples reference encyclopedia depend only on "official" even when there is good reason from officials to question it? This researcher, even though seen as having some of the wildest conspiracy theory around, actually uses real evidence and competent documentation of analysis. It is repeatable. Here are enlarged shots they have uploaded that show something not quite possible when using a scanner to capture from penciled originals that are blueprinted. http://algoxy.com/psych/whatis9-11Disinfo_anomalie.html Examine the title block. http://algoxy.com/psych/whatis9-11Disinfo_fakeplan.html They all have free hand lettering. This is not really conceivable for the final drawings of 2 of the tallest structures in the world. Also the drawings have no details on any of the needed horizontal and diagonal bracing needed. When the fact of the ex NYC mayor illegally taking the NYC plans for the buildings, (http://web.archive.org/web/20020224015919/http://www.nyclu.org/g_archive020602.html) the potential for a conspiracy is evidenced to a degree justifying the use of independent evidence IF such is verified. Verification appears robust. Can the official structure be verified by images from 9-11? Recall the towers engineer Leslie Robertson stated 2 days following 9-11 that the towers had a concrete core. http://web.archive.org/web/20040807085840/http://msnbc.msn.com/id/3069641/ 30yearconspiracy (talk) 22:59, 16 December 2009 (UTC)

Also "The standing consensus" derives its basic information of consensus from those sources that are in question. Is this an appropriate basis for selection of references and citations of Wikipedia? The actual moments of the buildings coming apart provide glimpses of the core structure and area. These are material facts and whatever is selected must be consistent with material facts from the scene of the crime when such exists. Is dismissal of such evidence proper when 16% of the US population believes something other than collape was to blame? That is nearly 50 million people? Logically structural designs are critical to understanding collapse and it is not shown that NIST had or used what they had but is shown that the building plans were illegally taken from NYC offices. 30yearconspiracy (talk) 00:22, 17 December 2009 (UTC)

I noticed that Bazant et. al. 2007 revision is a dead link to northwestern university. It mentions "concrete floors and core walls" perhaps that is why. The .pdf is available to download at teh following mediafire link to restore the final mathematical analysis citation. http://www.mediafire.com/?xmmfitynzrm 30yearconspiracy (talk) 02:29, 17 December 2009 (UTC)


 * I've left you a comment on your talk page. I think it will be most constructive if we discuss your approach there first. Most of us are familiar with the sorts of arguments you are making here and don't find them very convincing. (Basically, the article must be consistent, not with "the material facts", which we don't have access to, but the best sources we can find, which we all have equal access to.) The links that you say are dead work just fine for me.--Thomas B (talk) 06:18, 17 December 2009 (UTC)

This needs to be as public as possible because you have addressed no facts and provided no verification for changing the page while removing historical as well as contemporary citations all confirmed by material evidence under conditions and consistent with each other where official documents that should be available are not available. Material evidence of the crime scene always takes precedence for verification in competent analysis. This is an image of the WTC 2 concrete core. Absolutely NO STRUCTURAL STEEL is seen. This is the only image of either towers core with all exterior steel gone showing both sides of the core. http://algoxy.com/psych/images/southcorestands.gif Will wiki ignore the above image AND the information of Leslie Robertson 2 days after 9-11 when nearly 3,000 people died and the cause is thought be a form of collapse in a globally published magazine? This is a animated .gif showing the east wall of the WTC 1 concrete core. http://i716.photobucket.com/albums/ww168/S_N_A_F_U/core_animation_75.gif The original video, http://www.youtube.com/watch?v=-dWBBEtA5bI I have just verified in writing and provided material evidence verifying the written citation. You have not provided any such verification.

http://en.wikipedia.org/wiki/Wikipedia:Verifiability The threshold for inclusion in Wikipedia is verifiability, not truth—that is, whether readers are able to check that material added to Wikipedia has already been published by a reliable source, not whether we think it is true. Editors should provide a reliable source for quotations and for any material that is challenged or likely to be challenged, or the material may be removed.

Thomas Basboll wrote: "Hi again 30YC. It is understandable that you should think that the articles in an encyclopedia that "anyone can edit" should be open to the sorts of issues you raise."

I've raised issues of fact that are completely logical and provided verification justifying a point by point response and you've provided nothing. This, ........ is not good for wiki. Can you address verified fact such as I've posted now in a public situation? Thomas Basboll wrote: "But I'm sure you understand the difference between what you see as the verifiable facts of how the cores were constructed and what the mainstream consensus about the cores is. "

Mainstream concensus is misinformed and and posted facts verifying the assertion. I've shown violations of law that remove public documents from public offices and that US Senator expresses concern about a 30 year conspiracy. Address these point by point please. 30yearconspiracy (talk) 07:40, 17 December 2009 (UTC)
 * The "points" you have raised are nothing but the conspiratorial garbage that makes it's way through here. Most, not all of what I looked through can be classified as WP:FRINGE at the least, with a little WP:OR thrown in to break up the monotony. Soxwon (talk) 07:56, 17 December 2009 (UTC)
 * What you have written Soxwon is a series of cognitive distortions and you've posted no verified evidence. This is not good for wiki because I have posted a great deal of verified evidence which can only reasonably be countered with evidence.  30yearconspiracy (talk) 20:06, 17 December 2009 (UTC)
 * * sigh* No what I have written is how Wikipedia operates. If all of this information is as verifiable and noteworthy as you claim it should be easy to find a reputable, peer-reviewed source that examines it. The most reputable source I see amongst those is MSNBC. Soxwon (talk) 04:24, 18 December 2009 (UTC)
 * What you are suggesting "is how wiki operates" suggests that because some group of peers that are less accountable than you agreer with each other, night should be come day, white should become black, and all material evidence and individual accountability should be abandoned. 30yearconspiracy (talk) 07:27, 18 December 2009 (UTC)
 * No, what I am saying is that a responsible peer-review process is not impossible to overcome so long as the material is noteworthy and academically sound. Your ridiculous statements only serve to weaken your point. Soxwon (talk) 22:12, 19 December 2009 (UTC)

Concrete cores
It looks like the Finniston volume's statement is the best source for "concrete cores" that we have. It does seem to contradict the NIST report, but I think Wayne's explanation is the best one: the concrete in the cores were not taken to be a significant structural element in relation to the collapses. The best way to clarify this (to avoid confusion among people who have read Finniston and similar pre-9/11 accounts of the buildings' structure) is either to explicitly correct the "misconception" that there was a load-bearing concrete core or to say something a bit more detailed about the role of concrete in the "service cores" (i.e. stairwells and elevator shafts).--Thomas B (talk) 09:04, 17 December 2009 (UTC)


 * It seems that 30yearconspiracy has done the most research about those sources here. The Oxford Illustrated Encyclopedia of Invention and Technology is already a verified source. But what is a misconception and what is not? If you have a source from year 1992, the buildings collapsed on year 2001 and later on 2005 a contradictory document about the structures was published, then what should we believe? --Uikku (talk) 15:07, 17 December 2009 (UTC)


 * Like I say, it's a good source. But even good sources can contain mistakes, which are then corrected by other good sources. (In this case, I think we can agree that NIST and Bazant did some more detailed thinking about how the components of the core worked than Finniston's people.) It's not so much what we should believe but how we should present it in the article. The article explains the collapse exclusively with reference to the effect of the fires on the structural steel, not "reinforced concrete", and it does so because the only really good sources we have for that explanation are NIST (for collapse initiation) and Bazant (for progressive collapse), neither of whom explain the destruction of a concrete core. And NIST even explicitly says there was no (structurally relevant) concrete core. So, as was correctly pointed out above, it's a bit odd to have the design section describe a structure that the article does not explain the collapse of. We have to make a decision (fortunately there's no rush): do we count Finniston et al. as imprecise, perhaps even just plain wrong, or do we reject NIST's description of the structure, which makes it difficult to understand the section about the collapses themselves. Both sources are "reliable" in a basic sense, but since one of the sources is based on a more detailed and more recent study, I tend to favour the latter. Especially since it also allows to write a less confusing article.--Thomas B (talk) 19:37, 17 December 2009 (UTC)

In my view, the Finniston and the Bazant 2007 sources are important enough to merit the inclusion of the information about concrete core walls in the article. We should therefore cite both NIST and the other two sources, all with in-line attribution. Cs32en 17:42, 18 December 2009 (UTC)


 * Bazant 2007 ("What did and did not cause it?") talk about "concrete floors and core walls". That is not, to my mind, what we're taking Finniston to mean, namely, a concrete structural system.--Thomas B (talk) 19:08, 18 December 2009 (UTC)

Sources indicating that cores contained structural concrete

 * "The core columns were made of steel-reinforced concrete material and had a cross-sectional area of 0.2 suare meters."
 * Symposium presentation (essentially a working paper)--Thomas B (talk) 18:35, 19 December 2009 (UTC)


 * "Groundbreaking for construction of the World Trade Center took place on August 5, 1966. [...] The load carrying system was designed so that the steel facade would resist lateral and gravity forces and the interior concrete core would carry only gravity loads."
 * The main purpose of this report was not describe the structure of the towers or explain their collapse but to prepare an emergency response plan.--Thomas B (talk) 20:27, 19 December 2009 (UTC)


 * "Worried that the intense air pressure created by the buildings’ high speed elevators might buckle conventional shafts, engineers designed a solution using a drywall system fixed to the reinforced steel core."
 * ''A museum webpage'.--Thomas B (talk) 20:10, 19 December 2009 (UTC)


 * "The reinforced concrete core consisted of 44 columns and various lateral braces."
 * Symposium presentation (essentially a working paper)--Thomas B (talk) 18:35, 19 December 2009 (UTC)


 * "The 24m × 42m core was composed of 44 box columns. The core comprises steel beams and columns with reinforced concrete infill panels designed to share part of the gravity loads." (In: Eduardo Kausel (ed.), The Towers Lost and Beyond, MIT 2002)
 * The same chapter makes clear the cores columns were not made of reinforced concrete: "the use of reinforced concrete for the column cores in the WTC would have surely improved the thermal stability of the columns." (p. 103)--Thomas B (talk) 20:21, 19 December 2009 (UTC)
 * Which just shows that the authors have somewhat more detailed knowledge of the buildings. The existence of concrete infill panels and the non-existence of concrete columns is in no way contradictory. Yet, if the infill panels were designed "to share part of the gravity loads", they should have been included in NIST's and other author's analyses of the collapses. (Bazant apparently did so, as he mentions "concrete core walls".) Btw, Thomas, your various assessments of the different sources are, in my view, somewhat over the top, as I did not say that each source would be absolute proof of anything, and the status of the various sources is very obvious to the reader. It would be great to have some verbatim quotes from the non-concrete sources. Cs32en  00:36, 20 December 2009 (UTC)
 * I'm not trying to be dismissive. I'm just trying to clarify what kinds of sources we are talking about here. In the end, I think, we'll find a way to include the infill panels in a way that doesn't conflict with NIST/Bazant's description of the collapse mechanism.--Thomas B (talk) 08:29, 20 December 2009 (UTC)

Sources indicating that cores did not contain structural concrete
NIST and others. (Please add specific sources with references.)

"For a combination of historical, cultural and economic reasons, tall, concrete-core buildings dedicated to office use are unusual in New York, where builders prefer the wallboard-enclosed cores with steel frames that Mr. Robertson pioneered in the trade center." James Glanz, New York Times (October 23, 2002). Comparing 2 Sets Of Twin Towers; Malaysian Buildings Offered as Model. Retrieved December 19, 2009

Comments
If concrete was present in the core in the form of walls or concrete cladding on the columns, it would have relevance to the analysis of the effect of fire on the core. If reliable sources mention the presence of such concrete, even if it is not load bearing, I think that it should be mentioned as a counterpoint to NIST's assertion that "concrete was used only for the floor slabs". Wildbear (talk) 03:52, 19 December 2009 (UTC)

One possibility that may explain the confusion is that there were actually different designs for the World Trade Center at different times during the planning of the construction. While the structures may have been planned with steel-only cores, concrete may have been added at a later stage. The owner of the building would have an incentive not to publicize the change in design, especially if concrete structures were regarded as inappropriate for new office buildings at the time. Of course, it may have been the other way around, but, in that case, the change in design to a steel-only core would likely have been widely publicized, and it would be hard to explain how several reliable sources would reference the obsolete design then. This may also explain why the buildings' designs were never officially released, while there exist some "leaked" designs whose authenticity has been questioned. (These thoughts may help us to find appropriate sources, they are not intended for inclusion in the article.) Cs32en  09:01, 19 December 2009 (UTC)

Show me this document
This is a challenge to anyone: Find a technical document, dated before september 2001, that shows clearly what the WTC towers' cores were made of. Photographs during the construction are helpful but not enough, because the last phases of core construction are not shown. I have seen a picture of the collapsed WTC tower where the steel rebars of cast concrete are visible. So, there are some documents (written after september 2001) that insist that there was no concrete in the core, only steel columns. Then we have also some other sources before and after 2001 that insist that the core was made of steel and reinforced concrete. --Uikku (talk) 09:12, 23 December 2009 (UTC)

Conspiracy theory section heading
Since the consensus at WP, both here and on the related articles, is to call these ideas "conspiracy theories", does anyone one mind if we drop the "Controlled demolition" part in the heading? It will just look tidier.--Thomas B (talk) 09:06, 18 December 2009 (UTC)


 * Yes I object. I also don't think that there is consensus on calling related articles conspiracy theories but we grit our teeth and live with it.Tony0937 (talk) 17:45, 18 December 2009 (UTC)


 * In theory this would change the scope of the section, as there are conspiracy theories that don't involve controlled demolition, but since these theories are far too fringe to mention here I don't think it's a problem. Hut 8.5 19:24, 18 December 2009 (UTC)


 * Well, it would still implicitly be limited to WTC conspiracy theories (i.e.. conspiracy theories related to the collapse of the World Trade Center.)--Thomas B (talk) 19:27, 18 December 2009 (UTC)


 * There are a few people who think the collapse of the WTC was caused by a directed energy weapon, which isn't controlled demolition. Hut 8.5 19:46, 18 December 2009 (UTC)


 * If we want to be accurate then we need to include "controlled demolition" in the heading because that is the only hypothesis we should be linking to. I see no reason for the change other than to emphasize the pejorative in what is already a pejorative heading. If you want to include Mini Nukes and DEW I cannot see myself supporting that idea. Tony0937 (talk) 20:03, 18 December 2009 (UTC)


 * I don't want directed energy weapons included (as I said above, "these theories are far too fringe to mention here"). Hut 8.5 20:11, 18 December 2009 (UTC)

I'll have to think about this a bit more. I started with a purely stylistic issue, but there may be more to this. As I understand it, even some of the people who defend the theory find "controlled demolition" to be a misleading term, since the demolition was in many ways anything but controlled. Maybe NIST was right to call them just "alternative hypotheses" (covering explosives and missiles and, by extension, directed energy ... i.e. any source of additional destructive energy).--Thomas B (talk) 20:40, 18 December 2009 (UTC)

That section should be eliminated...the conspiracy theories surrounding this event are have no place in an article that is supposed to be based on the known scientific evidence...since no reputable scientists adhere to the CT regarding this event, little to no discussion is needed...we base our article on reliable references...since there are none that support these conspiracy theories, we violate several clauses of the NPOV policy.--MONGO 03:04, 19 December 2009 (UTC)


 * The argument for including the theories has always been that reliable sources like NIST and Bazant & Verdure explicitly reject them. Telling readers that NIST rejects the theory that explosives were used to bring down, e.g., WTC7 is simply more informative than leaving this information out. No reliable sources support the theory of pancake collapse (floor failure) either any more. But it is informative to include information about that view because part of the significance of NIST's work was to reject it. That is very much the case with CTs as well.--Thomas B (talk) 09:03, 19 December 2009 (UTC)


 * (ec) A large number of reliable source report on the conspiracy theories, therefore the information about them needs to be included in the article according to their due weight. Eliminating the information, as MONGO proposes, would violate our policy on the neutral point of view that all Wikipedia articles must follow. Cs32en  09:07, 19 December 2009 (UTC)


 * The fact that NIST explicitly rejects controlled demolition is not a good argument for including it here, because NIST also explicitly rejected the notion that missiles were fired at the towers. The pancake theory is a different matter entirely because it used to be widely accepted and so including it here documents how opinions on the cause of collapse have evolved over time. Controlled demolition has never been accepted by anything other than a very small minority.
 * Cs32en: we don't determine weight by how many reliable sources mention something but by how many support it. In the case of controlled demolition this is near-zero. It is certainly appropriate to include something to point readers to a dedicated article if they want to know more about it, but that doesn't necessarily mean we need a whole section discussing it. Hut 8.5 11:39, 20 December 2009 (UTC)


 * That's wrong, Hut 8.5. Notability, not acceptance is what determines whether something should be included in an article. The level of acceptance or non-acceptance is important with regard to the presentation of the information. From WP:FRINGE: "A fringe theory can be considered notable if it has been referenced extensively, and in a serious manner, in at least one major publication, or by a notable group or individual that is independent of the theory. References that debunk or disparage the fringe theory can also be adequate, as they establish the notability of the theory outside of its group of adherents." Cs32en  21:41, 20 December 2009 (UTC)


 * Notability is not the issue here. See Notability. Hut 8.5 21:54, 20 December 2009 (UTC)


 * From WP:DUE: 1. "If a viewpoint is held by a significant minority, then it should be easy to name prominent adherents." -> The CD hypothesis viewpoint is significant, as such prominent adherents can be named easily. 2. "To give undue weight to the view of a significant minority, or to include that of a tiny minority, might be misleading as to the shape of the dispute. Wikipedia aims to present competing views in proportion to their representation in reliable sources on the subject." -> The CD hypothesis viewpoint should be represented according to its due weight. Note that all characterization in these sentences refer to notability, not acceptance. Your reference refers to the notability guideline, not to notability as a concept, while I have quoted the fringe theories guideline. Cs32en  23:31, 20 December 2009 (UTC)

But the fringe theories guideline is referring to the notability guideline. This is shown by the fact that when it says "A fringe theory can be considered notable" it links the word "notable" to Notability (you omitted this in your quotation above). That section of WP:FRINGE is therefore not relevant to this discussion.

The controlled demolition conspiracy theory is not a significant minority view. It is a tiny minority view. WP:UNDUE does indeed say that "If a viewpoint is held by a significant minority, then it should be easy to name prominent adherents." You seem to have interpreted this as "If it is easy to name prominent adherents, then the viewpoint is held by a significant minority", which is not the same thing at all. The CD hypothesis should indeed be represented according to its due weight, which is very, very little.

From WP:UNDUE: "in determining proper weight, we consider a viewpoint's prevalence in reliable sources". Prevalence: "superior strength, reception" (Wiktionary). The fact that many reliable sources have discussed the conspiracy theories does not therefore mean that they should be given coverage here, because they have not had a good reception in those reliable sources. If you doubt this, look at the masters' thesis you linked to below, which despite discussing the collapse for 40 pages doesn't even mention controlled demolition. Hut 8.5 11:27, 21 December 2009 (UTC)


 * What number can be considered a significant minority? The 2006 Scripps Research Center Survey (obviously out of date so the number should be less today) indicated some 48 million (adult) Americans believe CD is very likely or somewhat likely. I would not call this number near zero or a tiny minority and due weight alone would require at least 15% of the article to be devoted to CD if followed to the letter. I'm not saying to give it more than a few paragraphs, I am just pointing out the problem with weight and perception of acceptance. Wayne (talk) 17:02, 21 December 2009 (UTC)


 * From WP:UNDUE: in determining proper weight, we consider a viewpoint's prevalence in reliable sources, not its prevalence among Wikipedia editors or the general public. Polls of the general public are therefore irrelevant to deciding how much weight to give a subject. <b style="color:#FF0000;">Hut 8.5</b> 17:30, 21 December 2009 (UTC)


 * When the fringe theories guideline links to the notability guideline, it does so because the notability guideline does not only contain guidance on how to decide on the inclusion of an article, but because it also contains some explanation of what notability means in the context of Wikipedia. The "if ... then" logical argument that you are presenting is of course, technically correct. You need to keep in mind, however, that the whole purpose of the sentences is to provide guidance on how to determine the relative number of people holding a specific viewpoint, it's definitely not to determine whether one can name prominent adherents. Does it make sense to predict whether one can name adherents on the basis of some speculation on the number of people holding a certain viewpoint? Of course not. So the "if ... then" construction, while somewhat sloppy from the point of view of logic, must be interpreted backwards: If you can name prominent adherents, then the viewpoint is being held by a significant minority. On the "prevalent" issue. Definitions that simply describe the word "prevalent" do not help very much here, as they always tacitly assume that we are dealing with something that is highly prevalent with regard to other things. This is not the case here, and the use of the word "prevalence" is therefore somewhat odd to begin with. Note that the same guideline uses "representation" instead of "prevalence" in another sentence, and that the sentence you have referred to is about a possible difference in prevalence between reliable sources and WP editors, it's a corollary rather than a basic definition. (You did not quote the rest of that sentence.) The definition of "due weight" as a consequence of the principle of neutrality, is: "Neutrality requires that the article should fairly represent all significant viewpoints that have been published by a reliable source, and should do so in proportion to the prominence of each." "Published" does not mean "supported" or "accepted". Cs32en  19:13, 21 December 2009 (UTC)


 * Taking this point by point:
 * The reason the section links to the notability guideline is because it is discussing how to apply the notability guideline to articles on fringe theories. The notability guideline is not a general rule on what is and is not considered significant enough to mention in a specific article. It is a rule specifying which topics can have articles devoted to them. It does not do anything else and it is irrelevant to this discussionn.
 * I don't understand your argument concerning prominent adherents. If your conclusion that having a prominent adherent makes a theory significant was correct, then all kinds of crazy theories would count as significant. I can name David Irving as a prominent advocate of holocaust denial. Does this make holocaust denial a significant viewpoint? Of course not. The sentence is saying that if a viewpoint is significant then the article could say something like "so-and-so believes X". Since CD is a tiny minority viewpoint this is not relevant here.
 * Using the word prevalent does not imply that something is highly prevalent with respect to something else, though that is true in this case, and I fail to see what relevance this comment has here. The "representation" part means the same thing - a source cannot represent a viewpoint simply by describing it.
 * the article should fairly represent all significant viewpoints that have been published by a reliable source does not mean that if a viewpoint has been published then it should be included. The CD theory is only adhered to by a small minority, and so it is not fair to give it coverage here (as it is not prominent). <b style="color:#FF0000;">Hut 8.5</b> 21:25, 21 December 2009 (UTC)
 * Note: I've left a message at Fringe theories/Noticeboard pointing here. <b style="color:#FF0000;">Hut 8.5</b> 21:28, 21 December 2009 (UTC)
 * Since this article is about the "collapse" other CT's such as government involvement and gamma rays etc from aliens are simply not related..."controlled demolition" would be the CT that relates to collapse...--MONGO 01:35, 23 December 2009 (UTC)

Remove all fringe material from mainstream articles unless third-party, independent, mainstream reliable sources discuss the fringe material
I encourage everyone discussing here to read and carefully consider WP:ONEWAY. This is a mainstream article, not a fringe article. To that end, unless independent, third-party, reliable mainstream sources have acknowledged that conspiracy theories are relevant to the actual collapse of the WTC, then we should not be including any mention at all of them in this article. ScienceApologist (talk) 21:33, 21 December 2009 (UTC)
 * Disagree, to a certain extent. Obviously the fringe theories being discussed here are eminently notable and worthy of mention. That rather goes without saying. Of course, it also goes with saying that they are, well, somewhat crackpot, but the article should make this clear too. However, their notability is not in question, and as a result there should be a brief paragraph or two here with a link provided to the more detailed "conspiracy theories surrounding" article, per WP:SS. Moreschi (talk) 22:06, 21 December 2009 (UTC)
 * Presumably the National Institute of Standards and Technology is a "third-party, independent, mainstream reliable source"; its "Final Reports of the Federal Building and Fire Investigation of the World Trade Center Disaster" discussed the fringe ideas in order to dismiss them (see NIST). Let Wikipedia do likewise. — Sizzle Flambé (☎/✍) 22:23, 21 December 2009 (UTC)
 * Precisely. Moreschi (talk) 22:34, 21 December 2009 (UTC)
 * I don't think we disagree, Moreschi. What makes you think that we do? ScienceApologist (talk) 23:13, 21 December 2009 (UTC)
 * It seems to me, SA, that you are arguing against inclusion of alternate theories, while moreschi argues that they do warrant mention. I could be wrong of course and you could in fact be arguing for inclusion in an indirect manner. Unomi (talk) 23:54, 21 December 2009 (UTC)
 * I am arguing for the exclusion of fringe proposals for which third-party independent sources do not exist which connect them to this topic. ScienceApologist (talk) 00:34, 22 December 2009 (UTC)
 * In that case it seems that you are in agreement with myself, moreschi and sizzle flambe in arguing for the inclusion of theories which have been treated by NIST and other notable reliable sources. Unomi (talk) 01:15, 22 December 2009 (UTC)
 * The very nature of conspiracies is that they are secretive, and if a conspiracy theory exists for which there is any credible evidence at all, it is no longer a conspiracy theory, but is now elevated to an alleged conspiracy. If an alleged conspiracy goes all the way to the top of the highest levels of government, then obviously any "reputable" sources that are in any way beholden to those sources must now come into question. An encyclopedia is supposed to be a tool for research and is supposed to be unbiased politically and in all other ways.  The fact that there ARE conspiracy theories or alleged conspiracies surrounding these significant events is very important information, both historically and analytically.  To exclude them, for whatever reason will amount to nothing less than historical censorship, thereby rendering Wikipedia a less important tool for serious research.  Also, according to a recent poll taken by Scripps Howard/Ohio University Poll, over 1/3rd of Americans now believe that the Federal government was somehow complicit in the events of 9/11 (Third of Americans suspect 9-11 government conspiracy). So this is not some small fringe issue, and as time passes, the importance of this aspect will only increase, because there IS merit to many of the claims made by leaders of the alleged conspiracy.  When someone as important as governor Bob Kerry, who served on the 9/11 Commission, admits that we are dealing with a 30-year conspiracy, that is not something to be taken lightly. Downisreallyup (talk) 22:34, 12 February 2010 (UTC)
 * As third-party, independent, mainstream reliable sources report and discuss the hypotheses, I don't see what the purpose of your comment might be, ScienceApologist . Cs32en  19:13, 22 December 2009 (UTC)
 * They do so, but generally only in passing for the most part...Bazant's et al work on "What Did and Did not Cause Collapse of WTC Twin Towers in New York" (and more similar material here)published in the Journal of Engineering Mechanics was one of the few works that have been done to silence much of the CT rumour mills. Citing that paper would be fine of course since it is from a highly respected source journal. But as it goes in the engineering literature, providing more than a passing mention here would be like reading a physical anthropology book that has entire chapters dedicated to discussion about mythical beasts like Bigfoot. Here we go again, those inclined to believe the impossible will argue to the end what portion of this article needs to discuss the preposterous.--MONGO 01:08, 23 December 2009 (UTC)
 * This article is only in part about science, it's about an important aspect of a historic event that has been reported on and discussed about in the society at large. Therefore, we cannot just look at scientific papers, but we need to look at reliable sources in general. Cs32en  04:20, 23 December 2009 (UTC)
 * Given that we have reliable sources of information about them, my basic argument for the inclusion of a discussion of the conspiracy theories is that many readers will have come to this article with those theories in mind. The idea of controlled demolition is one of the major reasons that lay people (i.e., people with no professional interest in how buildings collapse) begin to take an interest in the collapses. Knowing this, we should include some information from a mainstream perspective about those theories (i.e., the straightforward rejection of the claims they make) and a link to the more detailed article. I think MONGO's analogy is a stretch, and Cs32en is right that the collapse of the WTC is not just of interest to engineers; the article covers the death toll and environmental effects for good reasons. It is a signficant historical event. It seems to me that the most useful (though not perfect) analogy is the JFK assassination: not only are CTs of course mentioned in the article on the assasination itself, "the confusion surrounding the facts of the assassination" and Oliver Stone are mentioned even in JFK's biographical article .--Thomas B (talk) 15:20, 28 December 2009 (UTC)

Some links to sections of other articles about events that led to the emergence of alternative, fringe, or conspiracy theories: Robert F. Kennedy assassination, John F. Kennedy assassination, Madrid train bombings, 7 July 2005 London bombings, Attack on Pearl Harbor, Martin Luther King, Jr. assassination. Cs32en 03:23, 30 December 2009 (UTC)

Proposed text for controlled demolition conspiracy theory section
The controlled demolition conspiracy section contains various statements that do not seem essential to describe the theory. I suggest to replace the section with the folling content, based on the lead section of the article World Trade Center controlled demolition conspiracy theories. Cs32en 16:25, 26 December 2009 (UTC)

"Proponents of World Trade Center controlled demolition conspiracy theories, among them physicist Steven E. Jones, architect Richard Gage, software engineer Jim Hoffman, and theologian David Ray Griffin, argue that the collapse of the World Trade Center was not caused by the plane crash damage that occurred as part of the September 11, 2001 attacks, nor by resulting fire damage, but by explosives or incendiaries installed in the buildings in advance. According to them, the aircraft impacts and resulting fires could not have weakened the buildings sufficiently to initiate a catastrophic collapse, and that the buildings would not have collapsed completely, nor at the speeds that they did, without additional energy involved to weaken their structures. Though central to 9/11 conspiracy theorists, this hypothesis is rejected by the National Institute of Standards and Technology, which conducted the official investigation of the collapse, and by the mainstream engineering community."


 * No, way too much for a fringe theory. CD isn't in the mainstream and doesn't belong here. RxS (talk) 18:18, 26 December 2009 (UTC)


 * A shorter text, leaving out some info that is either not necessary because the article already provides context, or that is not necessary to understand what the claims are. Cs32en  19:21, 26 December 2009 (UTC)
 * "Proponents of controlled demolition conspiracy theories argue that the collapse was not caused by the plane crash damage, nor by resulting fire damage, but by explosives or incendiaries installed in the buildings in advance. According to them, the aircraft impacts and resulting fires could not have weakened the buildings sufficiently to initiate a complete and rapid collapse without additional energy involved to weaken their structures. This hypothesis is rejected by the National Institute of Standards and Technology, which conducted the official investigation of the collapse, and by the mainstream engineering community."


 * That's certainly better. It avoids defaming Richard Gage by calling him a "conspiracy theorist." Mr. Gage merely points out that the preponderance of evidence indicates that controlled demolition was used to commit this crime. He refuses to speculate as to who planted the explosives and points out, accurately, that he is only advocating the controlled demolition hypothesis and no conspiracy theory whatsoever. This statement can be find on the CBS station interview, if you can find that on the web. Wowest (talk) 06:07, 27 December 2009 (UTC)
 * I don't see how it's possible to have a controlled demolition without a conspiracy to do so. &mdash;  The Hand That Feeds You :Bite 17:46, 29 December 2009 (UTC)
 * All explanations I have read about 9/11 events include the existence of a conspiracy. I haven't seen yet any explanation without a conspiracy as an essential part. --Uikku (talk) 19:26, 29 December 2009 (UTC)

And the title?
My original question was about whether to change the section heading from "Controlled demolition conspiracy theories" to simply "Conspiracy theories". This is a purely stylistic suggestion. In my view, the longer heading lacks elegance. I assume that the words "controlled demolition" are a relic from the earlier heading "Controlled demolition hypothesis". At the time, the discussion no doubt centered on the "pejorative" sense of "conspiracy theories"; retaining the words "controlled demolition" has no effect on that discussion. The choice must be between "Conspiracy theories" and "Controlled demolition hypotheses"; "Controlled demolition conspiracy theories" is not a compromise. It's just poor style. Again, I'm talking only about the title: the section itself should of course present the most notable theory, i.e., CD.--Thomas B (talk) 07:46, 30 December 2009 (UTC)


 * I've created this version to show how I think the section should look (though the ref to the NIST report is wrong).--Thomas B (talk) 20:02, 6 January 2010 (UTC)

I concur with ScienceApologist. Fringe theories have no place in this article. We already have an entire article, World Trade Center controlled demolition conspiracy theories, devoted to WTC conspiracy theories. A Quest For Knowledge (talk) 23:12, 12 February 2010 (UTC)


 * Actually the official theory is theory of conspiracy organized by hijackers of planes etc... Cal it A. So which conspiracy theory do you thigh fringes? —Preceding unsigned comment added by 99.90.197.244 (talk) 07:45, 31 August 2010 (UTC)

Overview of collapse hypotheses (MIT thesis)
The following master thesis does give a good overview on the various hypotheses, some of them congruent, some different, others outright contradictory, that had been published by various authors and institutions by 2005. (None of these hypotheses is being characterized as a conspiracy theory.) Cs32en  19:50, 19 December 2009 (UTC)

WTC7 Bulge?
As far as I know, the "visible bulge" is not mentioned by NIST in its explanation of how WTC7 collapsed. That suggests that it is not a very relevant detail. My guess is that it is leftover from the old days when NIST had not yet offered a complete explanation. It sort of sticks out here and I think we should remove it.--Thomas B (talk) 08:48, 31 December 2009 (UTC)
 * Seeing no objections, I'm removing it.--Thomas B (talk) 19:36, 6 January 2010 (UTC)

Move details of WTC7 collapse?
Also, I wonder if we should move the very detailed section on the collapse of WTC7 from the WTC7 article to here. While the section is very rich, I think it would be easier to follow if it were distributed throughout this article (separating out design issues, the actual collapse mechanism, and the progress of the investigations). A summary should of course remain in the WTC7 article, much like the "destruction" section in the main WTC article .--Thomas B (talk) 08:48, 31 December 2009 (UTC)

Where is something about WTC7 collapse ? —Preceding unsigned comment added by 99.90.197.244 (talk) 07:35, 31 August 2010 (UTC)