The Line

June 6, 2013

I know it won't matter to those who continually insist otherwise, but for those of you who do actually pay attention to what someone says (as opposed to deciding that you know what they said and don't really need to read to confirm it), allow me to refresh everyone's memories as to both the nature and purpose of this example:

...

I have a dozen more examples of myself directly addressing what the purpose of these examples are, but I am not going to belabor the point further. I simply note that even now, the same incorrect claim is being made that the purpose of this example is to prove something about the collapse.

I’m sure you would forgive those making the alleged ‘incorrect claim’ since this thread and your model blatantly was intended to prove something about the WTC collapse. You stated it from the beginning: -

“

All right then, I thought a good example to start with is the collapse of the WTC floors. I've been seeing a claim that expresses incredulity at the claim that such a small portion of the tower could result in the total collapse of the floors underneath it unless there were explosives involved. This is usually backed up with videos of regular demolitions where the demolished building is cut more along the middle than the top (which, of course, begs the question as to how this

wouldn't

contradict the previous claim of explosives being placed at the top, but let's skip that for now).

Now, most people know the rejoinder to this is usually "Kinetic Energy!", but with little else to follow. While it is true that velocity adds energy to a moving object, few people really bother to take a good look at just

how much

energy we are talking about. Of course, in the real world there are many, many more variables involved, but for the purpose of answering the question of how just a few floors collapsing could result in a catastrophic failure of the entire tower, here is a very simplified version of how I understand it. I am by no means a master of physics, and mediocre at best on math, so feel free to correct me if you spot a mistake.

”

After that, I’m sure you understand why some might conclude your latest statement, “the same incorrect claim is being made that the purpose of this example is to prove something about the collapse” is disingenuous. If you are actually now revising your argument with that statement, that is fine, just say so – it would put us all in agreement. But please don’t get on your high horse and carry on like it was always your position, and that everyone else is out of order for pointing out what you now accept: the example is in no way analogous to the WTC collapses.

All I can say to that is that I have shown every step of my work, and none of my detractors have addressed any of them. Instead, the focus is on dismissing, devaluing, detracting, and denying, but unfortunately, no discussion.

...

When all is said and done, throughout all of this, the numbers remain in display, for everyone to see, with notes as to what I did. None of these numbers have been addressed to date. The whole focus of the detracters has been to try and divert attention from the example, instead of addressing the actual example.

The setup of the steps and errors that comprises, as they relate to reality of the WTC situation (or not), have certainly been addressed – it is actually you ignoring that criticism and continuing regardless with a deficient model. That needs to be addressed before anyone starts putting more effort into checking your actual number work. In other words, even if your numbers were correct, there is no point to it (I don’t think your numbers are correct in places, but like I say, due to the initially deficient model it isn’t worth the effort to address at the moment). I hope that explains why you aren’t generating the discussion you would like.

You can almost sense this palpable fear from the other camp. The amount of energy being expended here, the sheer over-the-top reaction to a simple physics demostration, it's baffling that any rational person would be so insecure in their position that even at the most basic of physics, the arguments at the high school level is viewed as a direct and imminent threat to their cherished conspiracy, to the point that there can be not the slightest bit of agreement, not the slightest hint of compromise; "No! Not only will there be absolutely no attempt to address the actual example, there will be no attempt to even accept that the example has any validity in any way, not even as a basicphysics, and anyone who even thinks of agreeing that as much as adding two masses together is anything other than absolutely wrong, and anything less than an insult to science and humanity, must be an utter fool!"

Did you just mention something about over-the-top reactions?

It’s not fear you sense aquatus, it is frustration, disdain and slight amusement that you are attempting to pass this off as in any way analogous to the WTC collapses (despite your denials).

Hey aquatus, would you like me to provide some suggestions of how to make your example somewhat more realistic/relevant so that the ‘other camp’ might start taking you seriously and get into a discussion of the actual numbers? Coming from the ‘other camp’ I think I'm in a reasonable position to do that.

June 6, 2013

Q, I'm the biggest critic of the official response to the 9/11 attacks I know. My criticism just doesn't rely upon implausible conspiracy theories or useless partisan politics that pack it up and go home as soon as the blue team is pulling the lever.

I know your position and I find myself in complete agreement with your posts elsewhere when it comes to the official response to the 9/11 attacks and the wider foreign policy of the United States (and others). I know you believe that suggestion of a 9/11 false flag detracts from those issues, but I never did understand how. In my opinion it is possible to criticise both a 9/11 false flag and the response to that event simultaneously. I’d love to discuss that point with you sometime.

I’m also on the same page in that neither does my criticism in discussing the 9/11 false flag, “rely upon implausible conspiracy theories or useless partisan politics”. No, there are very reasonable criticisms levelled at the official story of 9/11. Some of these are the exact same criticism you just levelled at aquatus. For example, here: -

He's overselling us on what he's doing with "actual science" but it cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables. I will agree to "I'm running values I made up with simplifications I made up using formulas I looked up in a physics textbook."

The above inconsideration of 9/11’s variables is exactly the same criticism to be made of NIST.

I’ll keep it short...

1.

NIST modelled a base case for the towers, using best estimates for the impacts and fires from observables in video footage. The model also subsequently provided a best match to the visible impact damage observed in video footage. This model

did not

produce a collapse initiation.

2.

NIST modelled another case for the towers, using more severe estimates from observables in video footage. The model subsequently did not provide a best match to the visible impact damage observed in video footage. This model

did

produce collapse initiation.

So which model is most considerate of 9/11’s variables?

Which model do you think NIST presented in their final collapse analysis?

The answer to the first question is 1.

The answer to the second question is 2.

But we know that 2. "cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables".

There are many more specific and detailed examples where this is the case.

June 6, 2013

I know your position and I find myself in complete agreement with your posts elsewhere when it comes to the official response to the 9/11 attacks and the wider foreign policy of the United States (and others). I know you believe that suggestion of a 9/11 false flag detracts from those issues, but I never did understand how. In my opinion it is possible to criticise both a 9/11 false flag and the response to that event simultaneously. I’d love to discuss that point with you sometime.

I’m also on the same page in that neither does my criticism in discussing the 9/11 false flag, “rely upon implausible conspiracy theories or useless partisan politics”. No, there are very reasonable criticisms levelled at the official story of 9/11. Some of these are the exact same criticism you just levelled at aquatus. For example, here: -

The above inconsideration of 9/11’s variables is exactly the same criticism to be made of NIST.

I’ll keep it short...

1.
NIST modelled a base case for the towers, using best estimates for the impacts and fires from observables in video footage. The model also subsequently provided a best match to the visible impact damage observed in video footage. This model
did not
produce a collapse initiation.

2.
NIST modelled another case for the towers, using more severe estimates from observables in video footage. The model subsequently did not provide a best match to the visible impact damage observed in video footage. This model
did
produce collapse initiation.

So which model is most considerate of 9/11’s variables?

Which model do you think NIST presented in their final collapse analysis?

The answer to the first question is 1.

The answer to the second question is 2.

But we know that 2. "cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables".

There are many more specific and detailed examples where this is the case.

False flag attacks can be cited throughout history and I don't deny there's an element of falsehood surrounding the 9/11 event. But I don't have to believe in nonsense like inside jobs e.g. rigging bombs in all those buildings behind everyone's backs and not getting caught or somehow bribing all of academia not to publish dissertations refuting NIST if there were any truth or validity to doing so. The reason why nobody has gotten a PhD from a top-tier engineering school is because the schools have a reputation to uphold and real academic research requires real scrutiny of its peers. I'm not even talking about getting a refutation published in a scientific journal here, although that would at least give the truther movement a shred of credibility. I won't deny it when I see it. I welcome it. So where is it?

As for NIST's two modelling cases, please cite from the NIST report what you're referring to so I can explore your claim.

Here are the analyses of the impacts. Saying they're based on observables (videos/photos) sounds disingenuous when it's not even the tip of the iceberg. What you're referring to FWIW appears to be on page lxxxvi. More than two cases are provided and I'm sorry to say that all of the modeled external damage looks extremely similar to the observed external damage.

http://www.nist.gov/customcf/get_pdf.cfm?pub_id=101428

June 6, 2013

False flag attacks can be cited throughout history and I don't deny there's an element of falsehood surrounding the 9/11 event. But I don't have to believe in nonsense like inside jobs e.g. rigging bombs in all those buildings behind everyone's backs and not getting caught...

I’d be interested to know how you think “rigging bombs in all those [three] buildings” is nonsense. The demolition setup would not be so difficult as you appear to think, providing conspirators with the right access. I would think that far more conspirators were involved in Operation Himmler, yet they did not get caught (at least not until after Germany lost the war). Obviously here we are not talking about a regular demolition team stampeding through the building! Rather, let me tell you a short true story in which the point will become clear...

Once upon a time, lived an American politician, Tom Leppert, a former White House Fellow (one of 13 chosen from 1,247 applicants) and future recipient of the Torch of Conscience award from the American Jewish Congress. In 1999, this politician became CEO of Turner Construction. This company contracted for Naval Sea Systems Command who were were undertaking research and development of various nano/super-thermite powders. It is reported, “At that time, this was the only reliable source of aluminium nanopowders in the United States.” Following restructuring of Turner Construction that same year, the company went on to contract for controlled demolition work in 2000.

So, we have a company there with a U.S./Jewish political connection, a link to procure thermetic materials, which has carried out controlled demolition work, and restructured a couple years prior 9/11. And which company do you think rented offices in both WTC towers? Which company held the contract to renovate the steelwork and fireproofing in those buildings? Which had been carried out in both impact zones. I’m sure you already know... it’s Turner Construction.

The above is all factual information. Leading from that...

All of the demolition materials and access required to the towers is right there, under the apparent guise of quite legitimate renovation works. Remember, the WTC tower core structures comprised largely of elevator shafts which provided access to the core columns. Such areas are not open to the many thousands of regular office occupants, but not so Turner Construction carrying out renovations in those areas. I don’t think it any kind of nonsense at all it was possible for firewall to be removed and replaced within the elevator shafts with demolition devices attached to the tower core columns. It's actually very simple.

Back to the start, now we have all that knowledge in mind: I’d be interested to know how you think “rigging bombs in all those [three] buildings” is nonsense.

... or somehow bribing all of academia not to publish dissertations refuting NIST if there were any truth or validity to doing so. The reason why nobody has gotten a PhD from a top-tier engineering school is because the schools have a reputation to uphold and real academic research requires real scrutiny of its peers. I'm not even talking about getting a refutation published in a scientific journal here, although that would at least give the truther movement a shred of credibility. I won't deny it when I see it. I welcome it. So where is it?

There are thousands of academics who do not accept the NIST report. But let me give you a good one: Professor James Quintiere, educated as a mechanical engineer, B.S. degree from New Jersey Institute of Technology (1962), and a M.S. (1966) and Ph.D. (1970) from New York University, NIST’s very own former Chief of the Fire Science and Engineering Division!

And what does he say of NIST’s study?

“I wish there would be a peer review of this. I think all the records that NIST has assembled should be archived. I would really like to see someone else take a look at what they’ve done; both structurally and from a fire point of view. I think the official conclusion that NIST arrived at is questionable.”

Here are excerpts of his statement to the Committee on Science, House of Representatives hearing: -

In my opinion, the WTC investigation by NIST falls short of expectations by not definitively finding cause, by not sufficiently linking recommendations of specificity to cause, by not fully invoking all of their authority to seek facts in the investigation, and by the guidance of government lawyers to deter rather than develop fact finding.

...

Scientists at NIST should be commended for their individual efforts in rising to the occasion of the WTC investigation. NIST should be commended for organizing an activity of this scale for the first time. However, there are some issues of concern that I will summarize. All of these have been submitted to NIST, but never acknowledged or answered. I will list some of these.

...

2. Why were not alternative collapse hypotheses investigated and discussed as NIST had stated repeatedly that they would do? Their current explanation for the collapse of the towers is critically based on an assumption that the insulation was removed from the steel in the path of the aircraft, particularly the core columns. NIST does not show calculations or experiments to satisfactorily confirm that the insulation was removed in the core. As some large aircraft components went directly through the buildings, and NIST indicates the others were splintered on impact, can they explain why these small splinters could still denude the steel?

3. Spoliation of a fire scene is a basis for destroying a legal case in an investigation. Most of the steel was discarded, although the key elements of the core steel were demographically labeled. A careful reading of the NIST report shows that they have no evidence that the temperatures they predict as necessary for failure are corroborated by findings of the little steel debris they have. Why hasn't NIST declared that this spoliation of the steel was a gross error?

4. NIST used computer models that they said have never been used in such an application before and are the state of the art. For this they should be commended for their skill. But the validation of these modeling results is in question. Others have computed aspects with different conclusions on the cause mechanism of the collapse. Moreover, it is common in fire investigation to compute a time-line and compare it to known events. NIST has not done that.

http://commdocs.hous...hsy24133_0f.htm

I hope you welcome this information and understand there is plenty of dissent against NIST’s study in the academic community.

As for NIST's two modelling cases, please cite from the NIST report what you're referring to so I can explore your claim.

Here are the analyses of the impacts. Saying they're based on observables (videos/photos) sounds disingenuous when it's not even the tip of the iceberg. What you're referring to FWIW appears to be on page lxxxvi. More than two cases are provided and I'm sorry to say that all of the modeled external damage looks extremely similar to the observed external damage.

http://www.nist.gov/...m?pub_id=101428

What you have there is NIST NCSTAR 1-2B. That is a part of the NIST NCSTAR 1-2 report – you would be better off starting there, at the beginning, for a full understanding of the models NIST created. It is a long and detailed process but, in that report, NIST summarise the situation I described: -

“For the more severe case, the impact speed was increased to the upper bound obtained from the analysis of aircraft impact conditions, while the aircraft vertical trajectory angle was reduced to impart more impact energy inward toward the core. A 5 percent increase in the total aircraft weight was considered for the more severe case, while the failure strain was varied to be 125 percent of the baseline value to inflict more damage on the towers. For the tower model, the failure strains of the tower steels were reduced to 80 percent of the baseline value, and the mass of the building contents was reduced. These variations contributed to more severe damage to the tower structure, by making the tower structure weaker and the aircraft structure stronger.”

http://www.nist.gov/...inalreports.cfm

The six variations described in the severe case above which, “contributed to more severe damage to the tower structure” in the model, were all moving away from the best estimate base case. In other words, moving away from the situation found most likely on 9/11.

I agree that the external damage caused by the base case and severe case simulations looks similar to the observed damage, but the best estimate base case was the best match. And it should be noted that any difference in the external visible impact damage carries through the whole structure that we cannot see (thus the severe case severed/damaged numerous more core columns than the base case). Anyhow, NIST confirm it here: -

“The overall agreement with the observed damage to the north wall was good for the base case and the more severe case, with the base case analysis providing the better match to the observed damage.”

So understanding that the base case comprised of best initial estimates and provided the better match to observable damage, please could you answer the question in my last post: which model is most considerate of 9/11’s variables?

Additional note: Yes, you are correct there were more than two cases modelled; there were three; a less severe case, a base case and a severe case. The first two did not produce collapse initiation in the models (which in itself shows the range of non-collapse discovered to be greater than the range of collapse) and so were dropped from NIST's final collapse analysis.

Edit: Oh lord, I see flyingswan hovering. Prepare for a lot of long ago debunked irrelevance to confuse the issue...

Edited June 6, 2013 by Q24

June 6, 2013

I love it when Q tries to use Quintiere as an expert witness in support of his demolition hypothesis. For a start, Quintiere has said that he doesn't believe the claims of explosives being used. Moreover, his dispute with NIST involves a claim that the insulation in the towers was substandard. If NIST, had incorporated Quintiere's claim, their models would have shown increased probability that the towers would collapse.

June 6, 2013

I love it when Q tries to use Quintiere as an expert witness in support of his demolition hypothesis. For a start, Quintiere has said that he doesn't believe the claims of explosives being used. Moreover, his dispute with NIST involves a claim that the insulation in the towers was substandard. If NIST, had incorporated Quintiere's claim, their models would have shown increased probability that the towers would collapse.

That’s it? That wasn’t too bad. Ok, flyingswan is patently wrong and confused: 1) he conceals that Quintiere’s dispute with NIST involved far more than a claim, “that the insulation in the towers was substandard”, anyone can read Quintiere’s full objections for themselves in his criticism I linked, 2) he forever seems to think I use Quintiere to support a case for demolition, rather than simply a demonstration that NIST’s conclusions are both lacking and questionable. Sure Quintiere has his own collapse theory, so do a lot of people (here are noted 1,932 such academics), but the common denominator is they all conclude the NIST study falls short.

Cue flyingswan raising one person whose faulty analysis he somehow thinks opposes those 1,932 but actually doesn’t, Gregory Urich... come on swanny... trot out the same old debunked arguments...

Think I’ll just wait for Yamato...

Edit: Just one thing I should have asked swanny, what do you think of aquatus’ model? I bet you love it don’t you? Of course you do :lol:

Edited June 6, 2013 by Q24

June 6, 2013

Cue flyingswan raising one person whose faulty analysis he somehow thinks opposes those 1,932 but actually doesn’t, Gregory Urich... come on swanny... trot out the same old debunked arguments...

Of course Urich trumps the AE911T case. He was himself a member of AE911T, but he looked at their case for controlled demolition and concluded that there wasn't a case: "...there is no claim favoring the controlled demolition hypothesis over NIST’s impact/fire/gravitational collapse hypothesis". He published an open letter to AE911T putting his arguments. That was back in 2009. If he didn't trump the AE911T arguments, why haven't AE911T been able to come up with an answer to him?

Here's his letter again:

http://www.cool-plac...RichardGage.pdf

Edit: Just one thing I should have asked swanny, what do you think of aquatus’ model? I bet you love it don’t you? Of course you do

I'm sorry you can't understand the physics of the situation and that you don't understand how engineers and physicists use models, but I suppose if you could understand an argument like aquatus', you wouldn't be a conspiracist. Edited June 6, 2013 by flyingswan

June 7, 2013

Q24 and Yamato (and to a lesser extent, Flyingswan), you have been told time and time again that it is not the purpose of this thread to discuss the credibility of a given claim or report, but rather to talk about the science behind it.

If you want to talk about how much explosive power it would take to accomplish a collapse, that is fine. Show your purpose, show your process, show your numbers. That is called "science".

If you want to talk about theoretical, not-actually-real, explosive devices, fine, I have no problem with using abstract forces in examples. But you do have to actually do something more than just mention it as a possibility. You do have to show what it would require to get the result you claim it did. Again, that is science. Just because it isn't real doesn't mean it isn't science.

Talking about who bribed whom is not science. Talking about which academics accept which report is not science. Talking about who made what claim is not science. Science is the numbers the people used to support their claims and the processes they followed to arrive at their conclusions. Heck, even the computer simulations can be science, as long as you actually talk about the simulations, and whether they took this into account, or that as part of their calculation, and why it would affect the final calculation (although, I do tend to think the simulations may be a bit too complex to fit with this thread's purpose of explaining the science simply enough for people to be able to follow).

The purpose of this thread is not to talk about who believes the insulation was substandard, but to show, with numbers or logic, how insulations works and how it is supposed to do this, but fails when x situation occurs. The purpose is not to say "it could have been explosives", but to say "a column this large would require x amount of explosives in this configuration".

The purpose of this thread, as it has been from the very beginning, is to keep things to the pure science of a given situation.

Please stop hijacking the thread with arguments about politics and credibility. Don't argue about why a paper hasn't been published, or about how the guy who made x claim, but not y claim. If you want to talk about the claim, show the claim and show the numbers. If you think they prove something, say so. If you are just trying to clarify a basic or general point, say so. Don't do the exact same circle dance that you can find in any other thread in this section of the forum.

June 7, 2013

Please bear in mind the warnings that I made:

at the beginning of the thread,

the beginning of the example,

several times during the middle of the example,

pretty much at least once a page,

this one here right now,

probably the one again at the end of this post,

and, I suspect, in my next post, when the usual suspects begin doing their ugly stepsisters routine claiming that I am saying that this is some sort of proof regarding the collapse of the WTC towers.

It isn't, it doesn't, it never has, it was never intended to. This is nothing more than a simple example of progressive collapse under acceleration that will demonstrate the interaction of forces and the differences in growth rates as the collapse progresses. This does not reflect the real world in any way other than as an abstract representation of numbers derived in a manner that cannot exist in the real world. This is nothing more than a mathematical construct reflecting a real world phenomena, but not defining it.

Our tower (at rest):

Floor 11: m= 200 kg = 1960 N

Floor 10: m= 200 kg = 1960 N

Floor 09: m= 400 kg = 3920 N

Floor 08: m= 800 kg = 7840 N

Floor 07: m= 1600 kg = 15,680 N

Floor 06: m= 3200 kg = 31,360 N

Floor 05: m= 6400 kg = 62,720 N

Floor 04: m= 12,800 kg = 125,440 N

Floor 03: m= 25,600 kg = 250,880 N

Floor 02: m= 51,200 kg = 501,760 N

The Collapse:

t = 0.00 s: f₁₁ and f₁₀ begin free-fall,

t = 0.78 s: f₁₀ impacts f₉
f_10/9: m' = 560 kg, v' = 3.14 m/s, F_avg = 11,552 N, loss = 40 kg,
[*]t = 1.30 s: f_10/9 impact f₈

f_10/9: m' = 1240 kg, v' = 5.14 m/s, F_avg = 77,156 N, loss = 120 kg,
[*]t = 1.35 s: f₁₁ impacts f_10/9/8

f_11/10/9/8: m' = 1400 kg, v' = 4.55 m/s, F_avg = 70,543 N, loss = 40 kg,
[*]t = 1.79 s: f_11/10/9/8 impact f₇

f_11/10/9/8/7: m' = 2720 kg, v' = 5.86 m/s, F_avg = 223,285 N, loss = 320 kg,
[*]t = 2.23 s: f_11/10/9/8/7 impact f₆

f_{11/10/9/8/7/6}: m' = 5230 kg, v' = 6.38 m/s, F_avg = 507,636 N, loss = 640 kg,
[*]t = 2.59 s: f_11/10/9/8/6 impact f₅

f_9/8/7/6/5: m' = 10, 390 kg, v' = 6.46 m/s, F_avg = 1,041,820 N, loss = 1240 kg,
[*]t = 2.95 s: f_8/7/6/5 impact f₄

f_8/7/6/5/4: m' = 20,790 kg, v' = 6.48 m/s, F_avg = 2,090,486 N, loss = 2400 kg,
[*]t = 3.31 s: f_7/6/5/4/ impact f₃

f_7/6/5/4/3: m' = 41,590 kg, v' = 6.49 m/s, F_avg = 4,199,683 N, loss = 4800 kg,
[*]t = 3.67 s: f_7/6/5/4/3 impact f₂

f_6/5/4/3/2: m' = 83,190 kg, v' = 6.49 m/s, F_avg = 8,401,387 N, loss = 9600 kg,
[*]t = 4.03s: f_5/4/3/2 impact Ground

Final Impact: m' = 83,190 kg, v' = 6.49 m/s, F_avg = 16,804,795 N,

Allright then, right off the bat, I did make a mistake in transcription. The time line of the collapse was off by a second from floor 5, so I corrected it. Again, there are many places where errors could occur, and I do have trouble with numbers, but I did do my best to cross-check and verify where I could, I showed my process in the first post where I began the collapse, and, of course, I may simply have transcribed the number incorrectly, as I did with the time line. If you spot an error, by all means, bring it up.

Which brings me to another error, although it doesn't affect the calculations in any way. I stated that I would simulate lost mass by dividing each floor into 10 blocks, each worth 20% of the original mass, and two blocks would be lost per slab per impact. I did calculate it this way, loosing two blocks, however, dividing a slab into 10 blocks means that each block is 10% of the original mass, for a

total loss

of 20% of the original mass per slab per impact. It was an error in explanation, not calculation. My apologies.

So...what the heck does this all mean?

Let's start by looking at the original claim that prompted this example:

A feature of the Twin Tower collapses that needed some explaining was how they pulverized themselves from the crash zones, staying centered all the way to the ground. Why didn't the tops topple, like any other vertical structure would topple from the fulcrum of the damaged area? Enter progressive collapse, a theory so versatile it applies to all of the accepted collapse theories. "Progressive collapse" would be the umbrella giving a legitimate sound to the domino, pancake, and zipper metaphors used by educators such as Thomas Eagar.

Progressive Collapse

Now, there are an abundance of errors in the above site and its related pages, most of them stemming from a lack of knoweldge in the subject (engineering). The specific one I will be referring to is the "pile-driver" theory, so-named due to a literal interpretation of a summary remark given by an engineer to a room full of engineers at Stanford University, without consideration that engineers do actually understand their field, and didn't need the speaker (Ron Hamburger, not Zdenek Bazant, as I have occasionally seen it attributed to) to clarify a relatively simple point that he has just spent the last 15 minutes explaining anyway.

According to the CT crowd, the (incorrect) claim here is: Engineers claim that the top of the WTC towers collapsed as a solid block, destroying the rest of the tower beneath it.

The CT then points out that this would never happen in real life (and they are correct. It never would. Which is why no engineer claims it does), and claims that the top floors could be seen tearing themselves apart (which, again, is correct, and not in debate among any engineers). The claim then goes on to refer to the whole concept as invalid because an aggregations of masses could not possibly have the same amount of energy that a solid block of mass has, just like a bag of sand could never have the force of a solid rock to the face (a surprisingly commonly used metaphor in these discussions. Why not the ground, or a table, why always the face?).

And there is the problem right there, in a nutshell. It is, in fact, the same problem that was addressed in this very thread a bit earlier. The problem is not an intellectual one, but a conceptual one. True, there is a certain amount of knowledge required to understand why it is wrong, but it really isn't anything that you won't recall from high school physics.

The idea stuck in people's head is that the amount of force generated by a loose aggregate will automatically spread itself out on the target and equalize in force, unlike that of a solid block, which will focus all its force on the impact point and therefore cause more damage. This is a mish-mash of real life mixing in with abstract energy concepts that we intuitively feel are right, but which actually turn out not to be supported when one looks at the basic science behind it.

As we can see in our model of a progressive collapse, the actual physical form of the objects is in actuality not very significant in terms of the behaviour of the energy. The magnitude of energy increases due to the acceleration and gain in mass, and it decreases due to deformation and loss of mass. It has nothing to do with being a rigid block or a bag of sand. The amount of energy is the same either way.

So, why is it that we intuitively feel that a bag of sand to the face is much more preferable than a rock?

Answer to come (after lunch).

June 7, 2013

I’d be interested to know how you think “rigging bombs in all those [three] buildings” is nonsense. The demolition setup would not be so difficult as you appear to think, providing conspirators with the right access. I would think that far more conspirators were involved in Operation Himmler, yet they did not get caught (at least not until after Germany lost the war). Obviously here we are not talking about a regular demolition team stampeding through the building! Rather, let me tell you a short true story in which the point will become clear...

Once upon a time, lived an American politician, Tom Leppert, a former White House Fellow (one of 13 chosen from 1,247 applicants) and future recipient of the Torch of Conscience award from the American Jewish Congress. In 1999, this politician became CEO of Turner Construction. This company contracted for Naval Sea Systems Command who were were undertaking research and development of various nano/super-thermite powders. It is reported, “At that time, this was the only reliable source of aluminium nanopowders in the United States.” Following restructuring of Turner Construction that same year, the company went on to contract for controlled demolition work in 2000.

So, we have a company there with a U.S./Jewish political connection, a link to procure thermetic materials, which has carried out controlled demolition work, and restructured a couple years prior 9/11. And which company do you think rented offices in both WTC towers? Which company held the contract to renovate the steelwork and fireproofing in those buildings? Which had been carried out in both impact zones. I’m sure you already know... it’s Turner Construction.

The above is all factual information. Leading from that...

All of the demolition materials and access required to the towers is right there, under the apparent guise of quite legitimate renovation works. Remember, the WTC tower core structures comprised largely of elevator shafts which provided access to the core columns. Such areas are not open to the many thousands of regular office occupants, but not so Turner Construction carrying out renovations in those areas. I don’t think it any kind of nonsense at all it was possible for firewall to be removed and replaced within the elevator shafts with demolition devices attached to the tower core columns. It's actually very simple.

Back to the start, now we have all that knowledge in mind: I’d be interested to know how you think “rigging bombs in all those [three] buildings” is nonsense.

There are thousands of academics who do not accept the NIST report. But let me give you a good one: Professor James Quintiere, educated as a mechanical engineer, B.S. degree from New Jersey Institute of Technology (1962), and a M.S. (1966) and Ph.D. (1970) from New York University, NIST’s very own former Chief of the Fire Science and Engineering Division!

And what does he say of NIST’s study?

“I wish there would be a peer review of this. I think all the records that NIST has assembled should be archived. I would really like to see someone else take a look at what they’ve done; both structurally and from a fire point of view. I think the official conclusion that NIST arrived at is questionable.”

Here are excerpts of his statement to the Committee on Science, House of Representatives hearing: -

In my opinion, the WTC investigation by NIST falls short of expectations by not definitively finding cause, by not sufficiently linking recommendations of specificity to cause, by not fully invoking all of their authority to seek facts in the investigation, and by the guidance of government lawyers to deter rather than develop fact finding.

...

Scientists at NIST should be commended for their individual efforts in rising to the occasion of the WTC investigation. NIST should be commended for organizing an activity of this scale for the first time. However, there are some issues of concern that I will summarize. All of these have been submitted to NIST, but never acknowledged or answered. I will list some of these.

...

2. Why were not alternative collapse hypotheses investigated and discussed as NIST had stated repeatedly that they would do? Their current explanation for the collapse of the towers is critically based on an assumption that the insulation was removed from the steel in the path of the aircraft, particularly the core columns. NIST does not show calculations or experiments to satisfactorily confirm that the insulation was removed in the core. As some large aircraft components went directly through the buildings, and NIST indicates the others were splintered on impact, can they explain why these small splinters could still denude the steel?

3. Spoliation of a fire scene is a basis for destroying a legal case in an investigation. Most of the steel was discarded, although the key elements of the core steel were demographically labeled. A careful reading of the NIST report shows that they have no evidence that the temperatures they predict as necessary for failure are corroborated by findings of the little steel debris they have. Why hasn't NIST declared that this spoliation of the steel was a gross error?

4. NIST used computer models that they said have never been used in such an application before and are the state of the art. For this they should be commended for their skill. But the validation of these modeling results is in question. Others have computed aspects with different conclusions on the cause mechanism of the collapse. Moreover, it is common in fire investigation to compute a time-line and compare it to known events. NIST has not done that.

http://commdocs.hous...hsy24133_0f.htm

I hope you welcome this information and understand there is plenty of dissent against NIST’s study in the academic community.

What you have there is NIST NCSTAR 1-2B. That is a part of the NIST NCSTAR 1-2 report – you would be better off starting there, at the beginning, for a full understanding of the models NIST created. It is a long and detailed process but, in that report, NIST summarise the situation I described: -

“For the more severe case, the impact speed was increased to the upper bound obtained from the analysis of aircraft impact conditions, while the aircraft vertical trajectory angle was reduced to impart more impact energy inward toward the core. A 5 percent increase in the total aircraft weight was considered for the more severe case, while the failure strain was varied to be 125 percent of the baseline value to inflict more damage on the towers. For the tower model, the failure strains of the tower steels were reduced to 80 percent of the baseline value, and the mass of the building contents was reduced. These variations contributed to more severe damage to the tower structure, by making the tower structure weaker and the aircraft structure stronger.”

http://www.nist.gov/...inalreports.cfm

The six variations described in the severe case above which, “contributed to more severe damage to the tower structure” in the model, were all moving away from the best estimate base case. In other words, moving away from the situation found most likely on 9/11.

I agree that the external damage caused by the base case and severe case simulations looks similar to the observed damage, but the best estimate base case was the best match. And it should be noted that any difference in the external visible impact damage carries through the whole structure that we cannot see (thus the severe case severed/damaged numerous more core columns than the base case). Anyhow, NIST confirm it here: -

“The overall agreement with the observed damage to the north wall was good for the base case and the more severe case, with the base case analysis providing the better match to the observed damage.”

So understanding that the base case comprised of best initial estimates and provided the better match to observable damage, please could you answer the question in my last post: which model is most considerate of 9/11’s variables?

Additional note: Yes, you are correct there were more than two cases modelled; there were three; a less severe case, a base case and a severe case. The first two did not produce collapse initiation in the models (which in itself shows the range of non-collapse discovered to be greater than the range of collapse) and so were dropped from NIST's final collapse analysis.

Edit: Oh lord, I see flyingswan hovering. Prepare for a lot of long ago debunked irrelevance to confuse the issue...

The NIST study was validated by studies done by MIT presented in the NIST report. I don't know how analyses by the best engineering school on the planet can give some guy with a bachelors degree the room to claim that it wasn't peer reviewed. That's just nonsense. Maybe not his peers, because they're way out of his league.

http://grad-schools....ls/eng-rankings

Again, I'll accept a scientific journal publication of any currently-employed professor(s) at any of the top-10 aforementioned universities with the emphasis on currently-employed. I will also accept any PhD dissertation (which is peer reviewed) challenging the conclusions of the NIST study from any of the top-10 aforementioned universities. Heck I'll accept the top-13 just because I'm feeling generous. Otherwise the thousands of sources, or hundreds of thousands of sources for that matter, do not meet my standard of academic scrutiny, but I'm sure they meet some peoples' standard of political scrutiny alright. I have a higher standard of belief on this than some, and that is my right. That my request hasn't been met in well over a decade now speaks volumes to me about what I can believe here. Our finest technical schools don't care one iota about politics and political agendas, they have a reputation to maintain. It's how they get funding and stay on top. Unless this simple request is met confirming one's belief in all of this conspiracy business refuting the NIST to that standard, we will agree to disagree no matter how long your replies become. The fact is these professors don't want to make fools of themselves and ruin their careers. I sat in the lecture halls, offices, cafeterias and hallways with some of the best engineering professors in the country in my field and none of them wanted anything to do with it.

I've heard so many lies, half truths and obfuscation coming from truther conspiracists, its legitimacy as a movement was destroyed long ago in my mind. I think rigging bombs is nonsense for a lot of reasons but mainly because I have no reason to believe in bombs in the first place (or other even wackier claims) when it's abundantly clear with my own eyes what brought those towers down on that horrible day, and the good work done by NIST matches to those observations. NIST has answered a lot of questions after the most comprehensive study on the 9/11 collapses around, and they're on the website. The problem with an event this complicated is there's always going to be more questions that go unanswered; this is not evidence of a conspiracy.

Edited June 7, 2013 by Yamato

June 7, 2013

One more thing, if Professor James Quintiere thinks in front of Congress that "I would really like to see someone else take a look at what they’ve done" well that's exactly what I'm asking for all along. Note that he's ignoring the "thousands of academic sources" who have done exactly that as well. So, how about you, James? Why don't you do what you would really like? Aren't you a peer? Get your colleagues together and someone else can take a look at it and then you can publish your review in a scientific journal, if you can.

June 7, 2013

Q24 and Yamato (and to a lesser extent, Flyingswan), you have been told time and time again that it is not the purpose of this thread to discuss the credibility of a given claim or report, but rather to talk about the science behind it.

If you want to talk about how much explosive power it would take to accomplish a collapse, that is fine. Show your purpose, show your process, show your numbers. That is called "science".

If you want to talk about theoretical, not-actually-real, explosive devices, fine, I have no problem with using abstract forces in examples. But you do have to actually do something more than just mention it as a possibility. You do have to show what it would require to get the result you claim it did. Again, that is science. Just because it isn't real doesn't mean it isn't science.

Talking about who bribed whom is not science. Talking about which academics accept which report is not science. Talking about who made what claim is not science. Science is the numbers the people used to support their claims and the processes they followed to arrive at their conclusions. Heck, even the computer simulations can be science, as long as you actually talk about the simulations, and whether they took this into account, or that as part of their calculation, and why it would affect the final calculation (although, I do tend to think the simulations may be a bit too complex to fit with this thread's purpose of explaining the science simply enough for people to be able to follow).

The purpose of this thread is not to talk about who believes the insulation was substandard, but to show, with numbers or logic, how insulations works and how it is supposed to do this, but fails when x situation occurs. The purpose is not to say "it could have been explosives", but to say "a column this large would require x amount of explosives in this configuration".

The purpose of this thread, as it has been from the very beginning, is to keep things to the pure science of a given situation.

Please stop hijacking the thread with arguments about politics and credibility. Don't argue about why a paper hasn't been published, or about how the guy who made x claim, but not y claim. If you want to talk about the claim, show the claim and show the numbers. If you think they prove something, say so. If you are just trying to clarify a basic or general point, say so. Don't do the exact same circle dance that you can find in any other thread in this section of the forum.

All you're really saying here is that we must apply science not to derail your thread. Incidentally, you'd have about zero participation from other posters in this thread so far if that is the case. You accept praise easily enough, but I already tried to offer criticism of your science here, but that wasn't acceptable either. So you're above criticism, and you get to dictate what we can and can't discuss here, with nobody yet doing what you're saying we must do.

Science is testing a hypothesis. Do you have one?

June 7, 2013

All you're really saying here is that we must apply science not to derail your thread.

YES!

Ideally, with some explanation.

Incidentally, you'd have about zero participation from other posters in this thread so far if that is the case.

You don't get credit for participating in soccer game if you insist on playing basketball.

You accept praise easily enough, but I already tried to offer criticism of your science here, but that wasn't acceptable either.

Where did you offer criticism of the science?

So you're above criticism,

I welcome it.

What I don't welcome is: "You should be talking about x instead, so everything you said should be ignored because it doesn't apply to x."

and you get to dictate what we can and can't discuss here,

No, but I do get to argue whether it is or it isn't on topic with the OP.

That's why people can start their own threads. So they can talk about something they want to talk about without getting drowned out by the people who insist on talking about the same thing being discussed in half-a-dozen other threads.

with nobody yet doing what you're saying we must do.

Including yourself.

Science is testing a hypothesis. Do you have one?

One part of science is testing a hypothesis. Generally, that's referred to as "research". This isn't a research thread.

Stop derailing the thread.

June 7, 2013

The NIST study was validated by studies done by MIT presented in the NIST report. I don't know how analyses by the best engineering school on the planet can give some guy with a bachelors degree the room to claim that it wasn't peer reviewed. That's just nonsense. Maybe not his peers, because they're way out of his league.

http://grad-schools....ls/eng-rankings

Again, I'll accept a scientific journal publication of any currently-employed professor(s) at any of the top-10 aforementioned universities with the emphasis on currently-employed. I will also accept any PhD dissertation (which is peer reviewed) challenging the conclusions of the NIST study from any of the top-10 aforementioned universities. Heck I'll accept the top-13 just because I'm feeling generous. Otherwise the thousands of sources, or hundreds of thousands of sources for that matter, do not meet my standard of academic scrutiny, but I'm sure they meet some peoples' standard of political scrutiny alright. I have a higher standard of belief on this than some, and that is my right. That my request hasn't been met in well over a decade now speaks volumes to me about what I can believe here. Our finest technical schools don't care one iota about politics and political agendas, they have a reputation to maintain. It's how they get funding and stay on top. Unless this simple request is met confirming one's belief in all of this conspiracy business refuting the NIST to that standard, we will agree to disagree no matter how long your replies become. The fact is these professors don't want to make fools of themselves and ruin their careers. I sat in the lecture halls, offices, cafeterias and hallways with some of the best engineering professors in the country in my field and none of them wanted anything to do with it.

I've heard so many lies, half truths and obfuscation coming from truther conspiracists, its legitimacy as a movement was destroyed long ago in my mind. I think rigging bombs is nonsense for a lot of reasons but mainly because I have no reason to believe in bombs in the first place (or other even wackier claims) when it's abundantly clear with my own eyes what brought those towers down on that horrible day, and the good work done by NIST matches to those observations. NIST has answered a lot of questions after the most comprehensive study on the 9/11 collapses around, and they're on the website. The problem with an event this complicated is there's always going to be more questions that go unanswered; this is not evidence of a conspiracy.

you say "I have no reason to believe in bombs in the first place", but i did give you a reason in the video posted here:

http://www.unexplained-mysteries.com/forum/index.php?showtopic=248571&st=60#entry4794938

you say "The NIST study was validated by studies done by MIT presented in the NIST report"

NIST did not (as far as i am aware) do any reporting on what happened after collapse initiation. the FAQ you referred to was published after their report as a statement in response to specific formal challenges. in point 2 they refer to momentum only in the context of the plane hitting the building (which was never an issue), in point 1 they are referring to the already rejected theory of floors (i mean just the horizontal you stand on) falling on floors (not storeys on storeys which includes the perimeter walls and the solid core structure) more in the comments here:

http://911blogger.com/news/2007-12-14/nist-publishes-supplement-answers-frequently-asked-questions

the NIST report defers to bazant for an explanation of what happened after collapse initiation (is that the MIT study you are referring to?), there have been rebuttals to bazant's hypothesis in that it makes unrealistic assumptions which favour his conclusion:

http://www.journalof911studies.com/volume/200704/NISTandDrBazant-SimultaneousFailure-WTCCollapseAnalysis2.pdf

and also that bazant's hypothesis requiring a jolt is contradicted by actual observations (there was no jolt)

http://www.journalof911studies.com/volume/2008/TheMissingJolt7.pdf

June 7, 2013

So, why is it that we intuitively feel that a bag of sand to the face is much more preferable than a rock?

We already know, according to our theoretical example, that our avalanche contains both "loose" energies (inelastic) and "rigid" energy (elastic). Additionally, since surface area is not part of any equation we did, we also know that the argument about the "sand" or the "block" striking uniformly is also irrelevant as far as the forces go. With or without surface area, the energies still reacted the way we expected them to react.

So, if the above tells us that a bag of sand is going to have the same amount of force as a rock, what is it that makes the sand feel less...hurty, than the rock?

The answer is time(t).

If we go back to our impulse calculation (F x t = impulse x change in momentum), we realise that force and time are inversely proportional. The longer the amount of time a force has to act on an object, the less force is needed to act on that subject to get the same amount of impulse. A bag of sand feels softer to us because it takes longer to impart its energy to our face. Similarly, boxers learn to "ride" the punch, to lessen the impact of the blow.

If we look back at our model, f₁₁'s impact, even though it was a high velocity impact, actually ended up reducing the overall velocity. This would not have occured if the mass it had hit was standing still. After all, an identical slab (f₁₀₎ fell less distance, yet imparted much more of its velocity, to the resting slab. But because the avalanche of mass was already moving downwards, it "rode the punch", so to speak. The force was still transmitted (except for the KE lost as upwards movement, deformation, and lost mass), but the amount of time it took ended up lowering the velocity.

This isn't just observable as an abstract physics problem. The "sap", a leather or canvas tube filled with iron filings or steel shot, has been a stand-by of the well-dressed mugger or gangster for quite some time. While it is true that the impact of the sap isn't quite as "striking" as that of a pipe or club, the force of the impact is still transmitted quite effectively, even though the surface area of the strikes isn't that different.

Which means that if we are dealing with an overloaded floor, it isn't the type of mass, whether "sand" or "rigid block", that will determine whether it collapses or not, but rather the amount of force it contains. 100 N applied in 1 second is the same as 1 N every second for 100 seconds. Once the upwards force of the resting slab is less than the downward force of the slab on top, down it will go, regardless of how fast or slow it changed.

So, one of the things we learn from this physics example is that the argument regarding the "pile-driver" and the "distribution of debris over the floor reducing force", isn't quite as strong a counterpoint as one might think, based on the amount of times it is trotted out as a first line of defense. If someone is trying to tell you that the table won't break if you pour a ton of sand on it very slowly, that's your cue to raise an eyebrow. Based on what you know of physics, you have reason to doubt the accuracy of that claim.

Edited June 7, 2013 by aquatus1

June 7, 2013

If someone is trying to tell you that the table won't break if you pour a ton of sand on it very slowly, that's your cue to raise an eyebrow.

nobody ever said that as far as I'm aware.

if the table was built to resist a ton then the table won't break if you pour a ton of sand on it slowly, the twin towers already supported the weight of it's mass for 30 years (and was built with a minimum safety factor of 5 for the cores and 3 for the walls).

June 7, 2013

This thread is for the purpose of setting up an experimental model to look at the physics behind a collapse.

Zeroing in on one aspect in order to gain information is common in science. This takes place in many scientific disciplines. Example, in Chemistry titration is a general class of experiment where a known property of one solution is used to infer an unknown property of another solution. You can set this up in a lab easily, many of us have done this in school...the set up isn't what's seen in "reality" yet it gives us information about the chemical reactions taking place. My point here is that aquatus is implementing a model situation to give information about the physics in a collapse.

This is not a difficult concept. Please refrain form other discussion and any personal denegration/ad hom remarks and address the physics being demonstrated by the model.

June 7, 2013

nobody ever said that as far as I'm aware.

Well, I gave you the link to it; there really isn't much else I can do for you at this point.

if the table was built to resist a ton then the table won't break if you pour a ton of sand on it slowly,

I'm not talking about the table. I'm talking about how the energy behaves. Specifically, I am showing how the same amount of force will be pressing down on the table regardless of whether it is applied slowly or quickly. I did that specifically to visualize the discrepancy in the claim that I both posted and linked to, which was specifically and incorrectly referenc--geez...why am I typing this?

No matter how much you insist on it, the purpose of this example is not to prove anything about the collapse. As long as you continue to claim that the answers do not refute the collapse, you will be CORRECT, because the answers are not meant to refute the collapse to begin with. I am talking about basic physics concepts, not engineering.

the twin towers already supported the weight of it's mass for 30 years (and was built with a minimum safety factor of 5 for the cores and 3 for the walls).

Support your claim, Little Fish. If you want to talk about the towers themselves, fine, but talk about the science, don't just casually mention some facts and go nowhere with them. How much force were the towers meant to hold up? How much force was generated by the avalanche? How do the cores and the walls influence the movement of energy? These are all things that are the subject of this thread.

If you want to talk about it, great, but show us your numbers. If you have a problem with my example, point to where you think something needs to be improved. If you have something additional to factor in, tell me what it is and how it can be factored in. Show your work, show your numbers, show that you understand what you are typing.

Edited June 7, 2013 by aquatus1

June 7, 2013

Aquatus, hello, not sure how to ask this, but lets go for it......

using the bag of sand analogy

if say the table could withstand the weight of the bag of sand if placed on the table, and not an ounce more.

now lets drop the bag onto the table (assuming all bits of sand strike at the same time) the weight plus the force from the fall would mean that the table would break, right? as this would combine to provide a force of X.

now if we pour half the bag onto the table. Then after a while pour the rest onto the table, we assume it would still collapse as, right?

but in these three examples we have three different values of X, dont we?

sorry if this sounds muddled, just really trying to grasp what you are saying.

June 7, 2013

Aquatus, hello, not sure how to ask this, but lets go for it......

using the bag of sand analogy

if say the table could withstand the weight of the bag of sand if placed on the table, and not an ounce more.

now lets drop the bag onto the table (assuming all bits of sand strike at the same time) the weight plus the force from the fall would mean that the table would break, right? as this would combine to provide a force of X.

now if we pour half the bag onto the table. Then after a while pour the rest onto the table, we assume it would still collapse as, right?

but in these three examples we have three different values of X, dont we?

sorry if this sounds muddled, just really trying to grasp what you are saying.

Ahh...this is a good question, it's just a little difficult to address because, like in the above situation, we have real-world concepts mixing into Newtonian physics (which, remember, don't actually apply to the real world, but rather to donkeys vs. carts, ducks vs. planes, and Klingon battlecruisers vs. Romulan Birds of Prey).

Okay, if I understand you correctly, we have a table force = x N, and we have a bag of sand with force = x N, meaning that both have the same mass.

In the world of Newtons Law's, every object has a given amount of inertia and every action has an equal and opposite reaction. This means that conservation of momentum will be all but perfect, which puts us in a bit of a bind. We cannot have a table that will move (break) only when x N of force are present; every bit of force encountered will result in an equal and opposite reaction, no matter how miniscule. If the table refuses to budge or break (acceleration or deformation), then the sand would have no choice but to bounce up and away. The energy must be conserved.

We are intuitively accustomed to things such as tension force and elastic force, so for us, we don't even notice that we are imparting real world properties to something that is only meant to represent an abstract force. Our Newtonian table will not flex with the weight and dissipate the force unless we calculate it to.

The long and short of it is that the above scenario can't actually exist in a Newtonian model, which is why the argument that the top floors of the WTC were calculated as a solid block instead of as an aggregate mass isn't a valid complaint. In our avalanche model, we had to calculate not just the impact force, but we also had to calculate the behaviour of the mass in impact, whether elastic or inelastic, in order to determine how it was going to interact with the floor it hit, and what the floor it hit would do in turn.

Now, having said all that, let's see if we can talk about the spirit of the question:

Let's say your table will only collapse when x amount of force is exceeded. We have a bag of sand with mass equal to x amount of force.

If we are able to magically (i.e. no extra forces) place the bag on the table, then no problem, both forces are equal, table and bag stay where they are.
If we drop the bag from a given height h, the m + a (produced by the h) will exceed x, and the table will break.

Now, from the same h, we pour half of f_sand x. We have the real world demanding we treat this as an inelastic collision, where the two masses merge but both stay still, but we have the Newtonian world demanding that something move, lest we violate conservation of momentum. Loss of kinetic energy is extremely difficult to calculate in the Newtonian world, because, unlike mass, it does depend a great deal on the form and consistency of the object. For the sake of the example, we are going to assume that the two masses merged (in other words, the sand stayed on the table, instead of flying off somewhere with equal and opposite acceleration to its own drop), but no movement resulted (the table did not break).

At this point, it becomes a logic problem:

If [^f^_sand^x/₂) * a] did not generate sufficient force to break the inertia of [f_table x],
Then we can conclude that [^f^_sand^x/₂) * a] would not be able to generate sufficient force to break the inertia of [f_table x] +the [¹/₂ f_sandx] we dropped on it previously.

In other words, when we calculated the impact of the first drop, the table had the mass to produce x N of force, and the sand only had enough to produce half of x N. In the second drop, after we added half the mass from the sand, the table + sand combo had the mass to produce 1.5(x) N, while the sand remained producing only half of x N.

Think of it in terms of breaking inertia instead of breaking a table. It takes x amount of energy to move the table from rest. If we increase the mass of table, it will take even more energy to move that table from rest.

Did that make anything clearer?

June 7, 2013

you say "I have no reason to believe in bombs in the first place", but i did give you a reason in the video posted here:

http://www.unexplain...60#entry4794938

you say "The NIST study was validated by studies done by MIT presented in the NIST report"

NIST did not (as far as i am aware) do any reporting on what happened after collapse initiation. the FAQ you referred to was published after their report as a statement in response to specific formal challenges. in point 2 they refer to momentum only in the context of the plane hitting the building (which was never an issue), in point 1 they are referring to the already rejected theory of floors (i mean just the horizontal you stand on) falling on floors (not storeys on storeys which includes the perimeter walls and the solid core structure) more in the comments here:

http://911blogger.co...asked-questions

the NIST report defers to bazant for an explanation of what happened after collapse initiation (is that the MIT study you are referring to?), there have been rebuttals to bazant's hypothesis in that it makes unrealistic assumptions which favour his conclusion:

http://www.journalof...seAnalysis2.pdf

and also that bazant's hypothesis requiring a jolt is contradicted by actual observations (there was no jolt)

http://www.journalof...issingJolt7.pdf

I'll let the discussion get back to the physics textbook, which is being enforced beyond the review of its peers so long as criticism is involved. That disqualified it immediately. What I get for stepping into another thread about 9/11, or in this case, 101 number crunching under a baited subject line. Whether a bag of sand can collapse a table depends on that table and that bag of sand, variables considerate of 9/11 Q repeatedly alluded to (dimensions, materials, structure, torsional/compressive/tensile strength, etc). Even accounting for every conceivable variable, for purposes of 9/11 analysis it's a waste of time. If what aquatus1 wants to discuss is all we're allowed to discuss here (wtf?) then my input is discriminated against so I'm done.

In parting, yes, I'm ignoring "the facts" (those "facts") because 9/11 blogs and guys with bachelors degrees citing 9/11 conspiracy grasping onto questions asked by experts aren't going to convince me. If you can find an engineering professor from MIT that disputes collapse initiation in a peer-reviewed publication then you'll convince me to look for additional causes of collapse but even then, I'm not jumping to any conclusion about "bombs". Lots of loud noises were heard that day. Nobody saw the damage up close those airliners caused and lived to tell about it, so the conspiracists feed on doubt and questions as if they're deliberate or malicious. Drawing real world conclusions about 9/11 won't be possible in this thread, and the sources you're pointing me to unfortunately suffer the same limitations. I'll study the nuts and bolts of top schools' peer-reviewed "science", insurance against time waste.

The video you had me look at, proof of explosions, isn't proof of bombs. Some of the testimony about explosions was actually describing the collapse, carefully edited to deceive. Deception is the primary ingredient of conspiracy. Occam's Razor. Here's your secondary explosions, conspiracy not required:

[media=]

[/media] Edited June 7, 2013 by Yamato

June 7, 2013

This thread is for the purpose of setting up an experimental model to look at the physics behind a collapse.

Then it should be moved out of the Conspiracies & Secret Societies board and into the Science board where it belongs so half of this thread's participants don't get ostracized for making comments on 9/11 conspiracy.

June 8, 2013

Being asked to stay on topic...

in a thread about the basic physics behind certain conspiracy claims...

The one thread out of several thousand in existence, several hundred created in the past year, and at least a dozen generated in the past month...

Any of which already plays home to these types of postings...

Where no participant has been "ostracized", despite the many times they were requested to get back on topic...

Where dozens of posts harassing, defaming, insulting, lying, and various other things that tend to be done to the ostracized are actually being done to the OP...

And yet, regardless, all are welcome to discuss the OP...as long as they actually discuss something in keeping with the OP...

That's your definition of "ostracized".

You are getting as bad as Q24. Really, all you have left to do is cut my sentences in half and claim it to be evidence of some kind.

But we have already witnessed in more than one thread your difficulty with definitions, haven't we? No need for other links; we have examples right here. Remember this one...?

He's overselling us on what he's doing with "actual science" but it cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables.

Overselling, as defined by Yamato:

Now, since we don't want a repeat of the first example, please listen carefully:

This is an example based on single-point masses reacting in perfect elastic or inelastic collisions.

In other words, the numbers are not, and do not, apply to anything other than the example shown here.

This is not an engineering diagram. This is not even implied to be the only way in which collapses occur. This does not reflect the real world in any way other than as an abstract representation of numbers derived in a manner that cannot exist in the real world. This is nothing more than a mathematical construct reflecting a real world phenomena, but not defining it.

The sole purpose of this example is to give people an idea of the massively unbalanced net forces that are generated in a progressive, linear, collision under the influence of gravity. Nothing more, nothing less. If there is some force you think might have a significant impact, by all means, tell me about it, and I'll see if I can add it to the equation. Otherwise, don't bust my chops because I called one of my abstract masses a concrete slab but didn't properly reference the tensile strength, shear force, or buckle point in the materials data worksheet published by the Association of Anal Retentive Engineers. Again, these are abstract masses, not "real" concrete slabs.

As I mentioned previously, in an avalanche scenario, forces are chaotically moving in all directions, in infinite variations, to the point where seemingly paradoxical situations become all but inevitable. In an avalanche situation, you will have objects ricocheting off each other, objects merging together, objects being forced upwards against gravity, and objects pulled downwards faster than freefall. The collapse of a physical structure like a building is an incredibly complex thing that is literally impossible to calculate in any specific way.

So yes, in order to show the accumulation of forces, some limitations need to be set. I have no intention of hiding any assumptions, and again, if you feel something isn't being done correctly or accurately, by all means, lines of discussion are open.

Now, here are some limitations and assumptions this example works under:

All forces are going to be either positive or negative (down or up)

In order to simulate the energy lost both as mass and as negative elastic momentum, each "slab" will be divided into 10 parts, and each collision will result in the loss of 20% of the mass of that slab (one block falling off each side of each slab, at every impact point). This is far higher than would be expected in a real world situation, particularly towards the end, but it does keep the math easier.

In order to replicate as close as possible the energy lost due to merging and deformation, half of the mass at impact will be calculated assuming perfectly inelastic collisions.

Each floor will be assigned an amount of force equal to the force pushing down on it, with the corresponding increase in mass. Again, in the real world you don't make a concrete slab twice as strong by placing another slab on top of it, but we work with what we got.

I did my best to double-check my numbers and I cross-checked them with each other (conservation of momentum, wherever I could, but I may have made an error in calculation, in formula, heck, I might have written it down wrong or typed it in wrong when moving it from pad to PC. Feel free to point out something you suspect is wrong. I will post the example after dinner. If anyone has any other limitations they would like to propose, by all means.

The example in the first page is Newtons Law's in their simplest forms, calculating the behaviour and force of single-point masses colliding in an inelastic trip straight into a final destination of infinite mass. There are no frictional forces, no vectors, plenty of assumptions, and an utter disregard for form and shape (Newton's Laws deal with single-point forces. Size and shape mean nothing to them).

The example isn't about any towers holding anything. The example uses single-point masses. The purpose is to demonstrate how rapidly the forces multiply together.

In the first example that I posted on the first page, the sole purpose was to explain the "Kinetic Energy!" rebuttal that is often used to counter the progressive collapse argument. Because all I was doing was showing the exponential increase in KE, it didn't really matter what the actual mass of the object was, as long as it was consistently applied. Hence I picked something easy to calculate, 200 kg, and applied it to all the slabs.

...

Now, of course, as I've stated on five seperate occasions, two of which were directly prior to beginning this example (and which resulted in yet another case of predicting behaviour, actively making a pre-emptive attempt to address, it, and yet again having someone carry out that specific behaviour anyways), this is not a real-life situation.

I am one hell of a salesman!

Incidentally, speaking of claims, did you ever get back to me regarding that one accusation you made?

You accept praise easily enough,

I was hoping you would because I went through and saw literally dozens and dozens of posts making accusations, insults, outright lies, slander, etc, etc, but the only response I found of myself accepting praise is:

I am the last person with any right to claim humility, but I do find this to be a perfect example of how utterly out of proportion some people's perspectives are.

but I already tried to offer criticism of your science here, but that wasn't acceptable either.

And it has already been explained why. I am performing a specific experiment. You demanded a different one be performed. You claimed my answers were invalid because your demanded experiment was not performed. That isn't criticizing science, not mine nor anyone's. That's complaining about not getting what you want.

Stop derailing the thread. I'm getting tired of having to show you your own posts where you are either wrong or lying. And don't tell the mods how to do their job.

Edited June 8, 2013 by aquatus1

June 8, 2013

"in a thread about the basic physics behind certain conspiracy claims..."

And thus my "derailment" has revealed the missing link required for your model to belong in the Conspiracies board without being able to discuss conspiracy. Please cite those physics.

Is your experiment addressing "the physics behind certain conspiracy claims"? If so, then how has my "derailment" brought that key point in fact out? If so, you should have established that in the OP. If you'd have cited the physics you're now referring to, that would have saved me from bothering with my criticism of your physics in the first place.

Cutting up the sentences of other posters is a poor way to discuss anything with them aquatus. and you habitually do that creating out-of-context banter instead of cogent, honest discussion. Not participating in conspiracy boards, I wasn't aware there was this much polarization between groups here that required the babysitting but if the above reply is any indication of how people respond to each other regarding 9/11 CT, then I can see how moderators would be required. "Dozens of posts harassing, defaming, insulting..." will get one banned, not give you a pass to ostracize posters on this board who've never done that. I was helping to steer you towards your purpose here and that was a big mistake because you're above such criticism.

If you are a "hell of a salesman", then you'll sell your model as relevant to 9/11 collapse to one of the known posters who favors 9/11 CT in those thousands and thousands of posts you're referring to, and change their mind. I was already in your boat and I jumped out.

June 8, 2013

Yamato, if you don't care for the subject of this thread you are free to open another thread to discuss what you desire. Attempting to re-define this topic is not a viable alternative.

Also, stop making the discussion personal, please address the physics involved with this particular model (not the personality of any other posters).

The Line

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