9/11 Experiments: The Arbitrator of Competing Hypotheses


Thanks for this clear teaching tool.

If this were a rational world...

I would hope that every high-school physics class could see and discuss this video. It provides a clear demonstration of several basic laws of physics. Plus, it shows how to make use of the experimental method for arriving at conclusions. It is crystal clear.

I would also hope that every member of Congress could view this video, and in fact every legislator in the country, at any level.

More WTC Model Experiments

WTC snow miniature demolition: http://www.youtube.com/watch?v=W9hnFPGxmVk

WTC2 Physical Model Demolition Test (part 1 of 4): http://www.youtube.com/watch?v=22--wjtBbI4
WTC2 Physical Model Demolition Test (part 2 of 4) - model failure: http://www.youtube.com/watch?v=S8IpW0Gf4no
WTC2 Physical Model Demolition Test (part 3 of 4) - late burn: http://www.youtube.com/watch?v=86buvzF5-JM
WTC2 Physical Model Demolition Test (part 4 of 4) - postmortem: http://www.youtube.com/watch?v=Wyy9JVoqXXQ

Excellent indeed


You made it so simple and clear. even Americans can understand it.

Wonderful video

The video does a respectable job of demonstrating the problem with the official story for how the WTC buildings came down, and contains a wonderful quote from Richard P. Feynman which sums up the situation well:

"It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong."

That's really all one needs to know to debunk the 9/11 deniers. That is the truth which shall set us free.

This Video Is A Keeper

It needs to be stored along with David Chandler's excellent work.

Exaggerated distance of initial drop

It would be more realistic to drop the upper blocks a distance approximately one fifteenth their height. This would correspond to a 15 story block dropping one story, This would be a closer analogy to what is claimed by NIST. It would further reinforce the ludicrousness of the official story - as it is pretty obvious that the upper block would immediately stop - doing very minor damage to itself and the lower block.

I am not suggesting that the big drops in the video are not good. They are EXCELLENT. But I think the whole thing could be made even more powerful with a verbal explanation that the drops in the experiment are many many times greater than the distances claimed for the top of the towers. We here at blogger know that - but the general public - seeing this for the first time - is probably not aware of the fact that the NIST championed drop is a tiny fraction of the drops demonstrated in these experiments.

Summing up: I think it would be good to do two drops for each material: One from the exaggerated height and one from a relative height corresponding to the drop claimed by NIST,for the towers. That would really drive the point home as it would be BEYOND OBVIOUS that the upper "block" could not possibly have destroyed the lower intact structure.

I hope this is not seen as a criticism - but as a way to make the experiment even more convincing.

As it is - it rates an A++

Thing is

To properly scale a physical model in accord with the towers, one would have to scale the characteristics of the materials and design to account for the smaller size, which would be quite a project. On the other hand, the models presented in the video are simply for testing the claims of Bazant et al., and in that regard the large drop does well to demonstrate how their theory utterly fails the test of reproducibility.

Realistic structure?

I've tried to design similar experiments. The problem with the structures that are used here is that they could presumably support many times their own weight. There was a YouTube video once that used a tower of five empty Coke cans glued together one on top of the other. Dropping another empty can on top left the tower (predictably) unscathed. The ratio of dead weight to load-bearing structure was simply wrong. The same is the case here.

You could put ten "towers" of ice on top of the model shown without doing any damage to the "lower block". The same goes for the cinder blocks. A lower section of ten cinderblocks could easily support the weight of another hundred (I'm guessing ... but certainly another 30 or 40, i.e., 3 or 4 times the weight.) But we wouldn't expect a WTC tower to be able to support even one more tower stacked directly on top of it. In that sense, when you think about it, a skyscraper is surprisingly fragile.

So, in order to make these experiments prove anything, we would need to start with a structure that would be crushed by a dead weight of, say, 3 times it's own weight placed on top. I've tried (unsuccessfully) to build something out of particle board floors and (I'm not kidding) macaroni columns. I've also tried it with dixie-cup columns and encyclopedia-volume floors. The model needs to include a lot of dead weight that does not contribute to load-bearing structure. Otherwise it simply doesn't test our intuitions. I haven't reached any conclusive results, but I just wanted to point out why I find the models presented here less than decisive.

Realistic Structure

I appreciate you comment but actually my intent was not to simulate the structure of the WTC towers. Had I welded up a structure built of steel, like the tower columns, you would not see any crushing whatsoever.
Rather, the intent was to demonstrate fundamental laws and dispute or confirm the three questions out lined, namely:

1. Will a block or any structure falling, speed up or slow down when it hits a similar structure below. Obviously it slowed down, but we did not observe that in the twin towers, (why not?) and that defied momentum laws (without some additional force like explosives.)

2. Bazant clearly stated, twice, that a simultaneous crushing of the upper and lower block cannot happen. We observed that indeed it could. Bazant is wrong.

3. Can any material whatsoever, regardless of configuration continue its fall all the way to the ground before it destroys itself? This is what Bazant is saying with all his differential equations. But Anders Bjorkman pointed out that no material, regardless of size, or configuration could do this, AS LONG AS it can support itself in the static condition.

And it makes no difference if its a solid block or simply an invisible "force" that can just hold any upper structure in the static condition, the falling block will ALWAYS slow down for an instant ( at least) , which was the purpose of the wood block drop. I doubt I could put a penny the upper wood block or it would collapse. It was that close to just being able to support the upper load. The point of that is that we certainly should have seen the upper “block” of the towers slow down, but we didn’t. Again it defies the momentum laws.

And is collapse really "inevitable? If so, why didn't the three structures collapse straight down all the way to the ground? The NIST assumption is wrong.

Finally, the debunkers can huff and puff all they want, but its meaningless without experiment. All they have to do is “prove it” with an experiment, or we are wasting our breath arguing with them.

I understand

I understand what you were trying to show and I'm not trying to debunk it. (I find the NIST explanation hard to believe/understand too.) I suppose I was looking at this video more as a piece of rhetoric than an attempt to understand something. You are trying to confront the viewer with his/her intuitions about how materials behave when they impact each other. My point with the Coke-can example is that I don't need an experiment to be reminded of how I would expect two essentially solid objects to behave when they hit each other. (By "solid" I mean simply that all their mass goes into their load-bearing structure. If we shot an empty coke can at another empty coke can at a speed that would damage to one of them, I would expect it to damage the other as well.

Bazant and the debunkers counter this intuition by reminding us that the structure, relative to the forces involves, was much closer to its threshold for collapse that, say, a stack of icecubes. Once we are reminded of that, we are put at a greater remove from our intuitions about how the materials involved would respond. Suddenly we don't really know what to expect. And that's why this film may not move ordinary people (not debunkers, who, as you say, are not really your audience) as much as you would like.

You don't understand yet

People who defend the official story for how the buildings came down aren't "debunkers", they are deniers, and Jon's experiments effectively debunk Bazant et al.'s arguments, since they make no stipulations on the "threshold for collapse." Furthermore, the "threshold for collapse" argument is debunked by Jon's wood block drop experiment. Understood?


I've looked at the issue for a long time. I believe a conversation about how/why the WTC collapsed is important, not just in regard to conclusion ("9/11 was an inside job") but in regard to the details. I'm very curious about the details, and NIST disappoints that curiosity at almost every turn. They don't seem interested in the details. That's why I follow 9/11 blogger and the truth movement more generally. It has a larger proportion of people who are interested in looking at the evidence in detail, and thinking various theories through. It's a long conversation, and this thread is nowhere near the point where any of us needs to be dismissed as a "denier" who refuses to understand. My comment was not very different from pointing out that the lighting could be improved, or that there was a spelling mistake on a slide. I was trying to suggest a way of showing the same thing, but in a more convincing way. Understand?

Please understand

My comments about those "who defend the official story for how the buildings came down" was not a reference to you, as I gathered you are undecided on that particular matter. Also, the term "collapsed" doesn't rightly represent what happened to the towers, which is why neither NIST nor any other defenders of the top-down collapse story can provide any experimental conformation to support their claims. Again, all one needs to know to debunk the 9/11 deniers is what Richard P. Feynman once noted:

"It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong."

Neither NIST nor any other deniers have managed to come anywhere close to demonstrating their theories as agreeing with experiment, nor will they ever do so, because those stories are wildly wrong. On the other hand, models of the buildings could easily be rigged with explosives and such to properly demonstrate reproducibly, because that's how the buildings were brought down.


Any old experiment doesn't test every theory. We would agree that if this experiment had been carried out with soccer balls it would have proven nothing. The chosen materials, and their arrangement, have to simulate the real-world structure we are testing our ideas about. So, it appears to be true that if you crash an ice cube into a tower of ten ice cubes, both are the worse for it, and about equally so. But I would not have expected anything else.

My problem here is that it is relatively easy to convince me (as Bazant tries to do) that the WTC wasn't very much "like" a tower of ice cubes. So my intuitions about ice cubes are easily rendered irrelevant. Now, if it is true (as I suspect it is) that those intuitions are more relevant than Bazant would have us believe, then we're in that intellectually harmful "2 + 2 = 5" situation. On the one hand, we know about ice cubes. On the other we are we being asked to believe that WTC collapsed "by gravity alone".

So, to keep ourselves sane, we need to design an experiment that bridges this gap between what's obviously true about pop cans, ice cubes, cinder blocks, etc. and what NIST and Bazant are claiming to be true about the WTC. An experiment that proves our intuitions about cinder blocks to be true doesn't really help. It's basically a vividly illustrated thought-experiment .

An experiment that seems possible with Jon's equipment would be to intersperse "columns" made out of pop cans between cinderblock (or garden-tile) "floors". Those cans can carry a suprising amount of dead weight, but if we build a structure that collapses (crushes itself) under about three times its own weight ... say, ten blocks separated by a certain amount of can-columns (determined by experiment) that collapses when thirty cinderblocks are added (3 to each floor) ... then we'd be approaching a structure that at least might progressively crush itself when the top tenth falls on the bottom nine-tenths.

I say it "might". That is, intuitively it could go either way. Showing how that structure in fact does or does not progressively collapse. Does or does not slow down (or "jolt") would have a real effect on people who are having a hard time making up their minds. Like I say, I don't think these experiments will have that effect, though I appreciate the spirit in which they've been carried out.


Bazant et al.'s arguments make no stipulations on the "threshold for collapse", so Jon's experiments using ice cubes effectively debunk them, and his wood block experiment debunks the "threshold for collapse" argument too. Please try your proposed experiment and see for yourself.

Means & ability

I'm not really interested in debunking anyone (as I said above). Jon seems to have access to equipment (and has skills) that would be useful. If the ice experiment "effectively debunked" something then the simple thought experiments (with billiard balls and hammers and cars) that introduced the film already had. The results of the experiments didn't surprise me, and therefore didn't make me smarter. Experiments are not just supposed to help you win an argument. They are supposed to settle a disagreement and teach how things behave under particular circumstances. In this case, I don't see how that's been accomplished. But Jon, like I say, has the means and the ability to do something more decisive much more quickly and easily than I could. Maybe I will one day. I can't make him do it, but you can't blame me for trying to spare myself the trouble.

Yet again

Bazant et al. made claims about how "how things behave under particular circumstances" which Jon's experiments demonstrate as wrong. However, if you want to be made smarter, you'll need to take the time to understand Bazant et al. claims well enough to comprehend the fact that Jon's experiments effectively debunk them. Put simply, others can lead you to watter, but drinking is up to you.

Take it from another point of view

(as Feynman says somewhere else on YouTube.) I think you're coming at my comment from the wrong end. I have read Bazant very closely, many times, and discussed it extensively with people on both sides (and in the middle). What I am saying is precisely that it is unclear that Bazant's analysis even implies that ice would not behave the way Jon demonstrates it to behave. It certainly makes no specific claims about what would happen to ice under the circumstances that Jon sets up.

To establish the facts he demonstrates, moreover, you don't have to do the experiment. You'd just have to ask Bazant (or someone using his argument) what they think would happen to a block of ice dropped onto another block of ice. Then the argument would begin on the same page, as it were, because they'd say exactly what Jon's experiment shows.

"Of course," they'd then say, "the WTC wasn't very much like that." Which you'd have to grant. So where did that get you? So, the hard part is not doing the experiment, but committing Bazant to the relevance of the experiment. Once you've done that, like I say, you don't even have to do the experiment. It would be like showing that his theory implies that pigs fly.

The experiment that I proposed would be less susceptible to being dismissed like this. If it shows that same thing, then the only recourse for the defender of the official view would have to do with how the structural principles "scale up". That, then, would be another discussion. In general, the sort of argument that Feynman is famous for in the case of the Challenger disaster can be very effective. I'm trying to explain why I don't think this is really that sort of argument.


Would it be possible to encode Bazant's theory as a computer program?

should be

I've always thought this would be a great way to defend the official explanation; so the lack of such a simulation counts as an argument for controlled demolition in my mind. If it were possible to show that a 100 story building with, say, five columns (one on each corner and one in the middle) could progressively collapse from somewhere near the top in a rigorous computer simulation (not just an animation, of course), using Bazant's assumptions about the column's properties, then it seems worth the effort to produce one. (You'd think that even just for teaching purposes (i.e., in engineering school), you'd want to illustrate the mechanics of the collapse in details. Yet I haven't been able to find a single detailed account of what happened to the structure. Just Bazant's one-column model.)

One could still discuss the assumptions, of course. But the simulation would be great way of bringing some order into the debate. Mainstream engineers,as you may know, called for a full simulation of the progressive collapse already five years ago.


Not possible

It's not possible to construct a simulation of the official story for how the towers came down (or WTC 7) while reasonably adhering to the design of the buildings and the laws of physics, because the official story isn't even close to what is physically possible.

You may be right

Like I say, I suspect that the reason such a simulation doesn't exist is that you are right. After all, it is possible to model the collapse of simple structures.


Why not go the simpler and reverse route

and set up a computer simulation using your ice (or other material) experiment and calculate how much energy would be needed for the top structure to destroy the bottom structure while adhering to the rules set by Bazant? In this way, you can prove what is and is not possible with this model and probably also prove that what Bazant is actually saying is that his rules only apply to skyscrapers.


I wonder how accurately a simulation must be rendered before it constitutes physical evidence in a particular case.

How about ANY structure that "collapses" as did the Twin Towers

I would love to see a structure built of paper-thin sugar wafers and small-gage pencil lead collapse in a way that even approaches the way the towers collapse. I can't think of any example where something collapses under its own weight in such a way. You can even put a layer of flower on each wafer to add the the weight and simulate the fine powder we see ejected in the videos.


NIST's WTC7 theory doesn't accurately model reality either but they just produced an inaccurate simulation.

Is it possible that if Bazant's theory (with all its simplistic/false assumptions) were run as a simulation then his tower wouldn't behave the way he assumes?


NIST never provides a collapse scenario

One reason why no one could produce a simulation of the "collapse" adhering to what is in the NIST report is that there is no description nor explanation of the collapse beyond 'Bazant said so'. That is part of the problem. There is almost nothing to refute because there is almost nothing actually being said about the topic.

If you go back to Bazant, he doesn't provide any kind of collapse model using the structural characteristics of the buildings. IIRC he used some kind of hand waving BS about Van Der Waals potential energy, and hopes the reader will be sufficiently intimidated so as to not question his reasoning(sic).

As show in the video

Bazant et al. claimed:

"Consequently the effect of the initial two-way crush is imperceptible and the hypothesis that the crush-down and crush-up cannot occur simultaneously is almost exact."

Jon's ice and mortar experiments, though simple, effectively debunk that claim. More complex experiments of course could provide even better demonstrations of how wrong Bazant et al. are, but no experiment could rightly be expected to shake the faith of those who believe the official story despite the utter lack of experimental validation to support it.

Almost exact

Bazant et al. seem to have done some calculations (reported in their appendix). While it's mostly greek to me, it does seem to be based on assumptions about the strength of the columns, which are, they note, different in the two cases. They conclude as follows:

"It is found that, immediately after the first critical story collapses, crush fronts will propagate both downward and upward. However, the crush-up front will advance into the overlying story by only about 1% of its original height h and then stop. Consequently, the effect of the initial two-way crush is imperceptible and the original hypothesis that the crush-down and crush-up cannot occur simultaneously is almost exact."

That is, they do not deny that there will simultaneous crush up and crush down. What they say is that, with the materials and forces that were involved, the crush-up would be negligible relative to the crush down. That is, saying that "the crush-down and crush-up cannot occur simultaneously" is not true, but it "is almost exact." I don't question your right to think they're bullshitting you. But surely an experiment with ice does not "effectively debunk" a calculation that acknowledge the same effect in steel columns but concludes that it will be much smaller. Moreover: the difference in crush up and crush down is not quantified in Jon's experiment. What if we had to conlude it was 30/70? Would it then be suprising that same difference in WTC steel was 1/99?

It would be a miracle

Hence the reason there is no semblence of expemrnetal conformation to support Bazant et al.'s claims.

You got it

Pavlovian Dogcatcher, you understand it. My goal was certainly not to mimic the actual collapse sequence of the towers per se, using steel and concrete. The object is to demonstrate the impossibility of a constantly accelerating motion of the tower if it hit any equivalent force that once supported it (the wood block drop).

The intent was also to demonstrate how the "officially endorsed" Bazant paper, about “crushing” a larger block with a smaller block cannot be supported by experiment, and to disprove their statement about the impossibility of a simultaneous destruction of two "blocks".

But it’s NOT intended to be a replica of the towers by any means ~ its all about the motion of the “collapse”.

the point is . . .

>>The object is to demonstrate the impossibility of a constantly accelerating motion of the tower if it hit any equivalent force that once supported it (the wood block drop).

It sounds like Thomas Basboll helped you clarify what exactly your intent was, beyond just a video. There will be many others like him with the same viewpoint, so it doesn't necessarily help to just say "you got it" to one person, and "you didn't" to another.

Find a way to get your point across specifically to people like Thomas, i.e., adding text, or a message, etc.

Good point...

You do make a good point. I had no intent to slight anyone, but I can certainly see how it could be interpreted that way. ......sorry about that.

no slight felt

well, maybe a slight slight. ;-) but I've been at this for so long that I understand the terms of the discussion and how quickly one gets shunted off the middle ground. no biggie.


Thank you for this. I feel a little better now. Please spread this in mass.

Remember who the audience is

This is for Americans of the idiot box generation. ;-)

It need not be intelligent or accurate. KISS

All that is needed is to show the basic principle that the upper part., no matter what is is made of, will be destroyed in the process of destroying an equal portion of the structure below.

The only way to improve this video is to have a babe in a bikini to do the dropping.

There's more to it: top was weaker than bottom

The Bazant "crush down" then "crush up" theory^h^h^h^h^h^hhypothe^h^h^h^h^h^hnonsense fails to address the fact that the bottom floors of the WTC Twin Towers were constructed of much stronger and heavier components than the fictional top "plunger block". The idea that this lighter, weaker component crushed the stronger heavier component and then disintegrated when it hit the ground is physically impossible.

Excellent point!

I was thinking the same thing when Jon rotated the mortar block at different angles to show that even with a terribly imperfect lower structure -- that was in no way meticulously and uniformly designed like the one for WTC 1, 2, & 7 -- the upper block still could not completely destroy it.

Excellent experiment people can do at home

Ok to add this experiment to http://www.911Experiments.org ?
Experiments you can do at home to test the Official Conspiracy Theory.

O.K. to add

Sure, its o.k. to add to that site.

another experiment

great job!!! it would be cool to demonstrate 110 stories falling and what their acceleration rates would be if you suspended bricks with your guide rails and started an initiation sequence. of course the suspension would need to be something very minimal to simulate zero resistance...bricks suspended in air.

Really beautiful ...

fantastic experimentation, highlighting the critical factors appropriately ... simple, clear, convincing ... Galileo himself would be impressed


Clap your hands really hard until they sting.

Does just the right one sting?
Does just the left one sting?

Do they both sting?


Thank you

What would George Orwell say?

"We have now sunk to a depth at which restatement of the obvious is the first duty of intelligent men."
George Orwell


Orwell had one of his characters say "...things unsupported fall". He was way ahead of NIST.

The glowing molten metal flowing from WTC 2 is better proof

I'm not saying the efforts to experimentally model to "collapse" of the 3 WTC towers is a waste of time. This backyard video presents more physical testing of the NIST collapse fairytale than anything NIST conducted.

My father, the structural engineer, has spent years griding down pencil lead trying to prove the NIST fairytale is complete rubbish. I admire his diligence, but I believe he has taken poison bait. Bertrand Russell criticized Alexander the Great for his approach to dealing with the Gordian Knot. Russell argued that Alexander demonstrated little more than his impatience and unintellectual brutishness. The challenge was not to release what was bound by the knot, but rather to solve the puzzle. In the case of 9/11, I'll side with Alexander.

IMO it is very difficult to argue Newton's Laws in this situation. Not that they don't apply. It's just that there are too many hard to quantify variables. Mathematical proof of the blatantly obvious would be difficult to provide. Surprisingly, it seems that quantum physics provides the elegant and simple proof that something other than office fires was at work in destroying the buildings.

I've written about this several times before. Unfortunately I was unable keep my server on line. You can find copies of work in other places. Google for "Glaring Proof of Something Hotter than an Office Fire in WTC2".

I just hit this on a search:

See this in particular:


To me your arguments, or whoever's, in that paper look, as the author says, irrefutable. Here is the one I mean:

Actually, when I first saw video of bright molten metal spewing out of one of the towers, I assumed the jig was up. I assumed the whole official hypothesis would be unmasked in virtually every thinking person's mind. I am still dumbfounded as to why it didn't work out that way.

Do others feel likewise, about the molten metal? If so maybe we could do more with that evidence.


Agreed student, when I saw that too I thought the same thing. NIST's explanation was that it was aluminum from the plane parts. How laughable is that, but deniers and defenders cling to it's veracity. Prof Jones did an experiment showing how molten aluminum looks nothing like the substance that was coming out of tower 2. He put additives in it and to no avail, it still looked silvery/grey. In another presenation, he edited and slowed down the video to keep the molten iron flowing out of the building in a single frame so you can see the color of it even better.

How anyone believes it is beyond me. Anyone can see the color of the molten liquid coming out and can tell it is very very hot stuff. When I have seen debunkers on youtube try to show the ineffectiveness of thermite by showing reactions, I have pointed out how the color the thermite reaction looks excactly like the substance coming out. They still cling to the NIST explanation.

I am not sure what else one can do on this. Maybe a decent youtube showing thermite and the tower 2 substance focusing on the color? The color helps determine temperature. Just thinkin out loud..


Who rejects the molten metal evidence?

I suspect there are few people who would reject the brightly glowing molten metal evidence if they actually examined it. I showed it to my coworker, and he didn't even try to argue against it. He simply said "you're right". The big problem, as I see it, is to get people to even look at the evidence.

Making the point clearer

Perhaps building a model that sort of looks like the towers contributes to confusion about what you are trying to show. Building a model will always be problematic because deniers could always complain it is not close enough, which is what Thomas Basboll was trying to point out, I believe, and the more detailed and complex it is, the harder it is for laymen to understand. I am in favor of breaking it down to the simple and more obvious principles that always apply to everything.

You don't need to have a small block falling on a larger block in order to show the principle that the collision of two blocks made of similar materials will result in both being damaged equally. This happens regardless of which one is moving faster than the other one. It is also true regardless of how the materials are constructed, if they are both equal. It doesn't matter if the upper block is falling down or the lower block is moving up to hit the upper block. It doesn't matter if the blocks, or balls or whatever, are colliding horizontally. It doesn't matter how elastic or inelastic the collisions are. Equal and opposite forces are exactly that.

In fact, the lower structure of the towers was much stronger and denser than the upper structure, and it is quite obvious, in the case of WTC1 and 2, that lots of material is flying out rather falling straight down, so that should be further proof that it makes no sense for the upper structure to remain undamaged (except for, what, 1%??!?) during the entire collapse until it reaches the ground. Come on.. this is just laughable.

I'm still working on my 911PhysicsTruth site. This video will be a valuable addition. Thanks for your work.