Szamboti's Missing Jolt paper

[beachnut]

.17 seconds / 5 = .034 seconds. They had lots of frames to work with, so just used every 5th one.

You post is dumb; pure stupid when you think about it. (the "lots of frames to work with", stundie stuff)

One pixel = .88 feet. Smallest time 0.0333333 for a frame.
They had to use five frames because the WTC falling one pixel took FIVE FRAMES.

To see the jolt we need about 1000 frames a second resolution. Plus we need to be closer so a pixel is a few inches. If you don’t understand this you will not understand that the paper in question is pure JUNK.

This means there is no resolution in time, or space to show a 31 G jolt that takes place in 2 ms. Darn, physics, a practical use of physics will cure your inability to understand the paper is wrong because the two fantasyland authors are incompetent on the simple stuff.

About the time of the first impact, we could see no pixel movement, one pixel movement, or two pixel movement in 0.0333 seconds. But at the impact time the only movement detected is on pixel, near the speed at impact. We are looking for a 2 f/s deceleration in a small time, much shorter than one frame of 0.0333 seconds. LOL!!!!!
Your inability to solve this exposes your complete lack of practical physics. If you do not understand my simple analysis, or you can’t correct it, or you can’t explain it, you lack the ability to see the author’s paper is flawed in fundamental physics, sampling theory, and more.

Use some real physics like a skeptic would. Do you even know what the jolt decrease in velocity is? Take a guess? Is it 0.66m/s? Do you, can you do this physics stuff?

If you don’t know there is not enough resolution, you have flunked this physics class and have nothing to stand on. Still no evidence to go with your false ideas about 911.

 

[jhunter1163]

Either (Dave Rogers made a mistake), or my understanding/guess about how Szamboti and MacQueen did their calcs is wrong.

Since Dave Rogers is a physicist by trade, my money is on the second option here.

 

[Furcifer]

.17 seconds / 5 = .034 seconds. They had lots of frames to work with, so just used every 5th one.

Yah, but the points. The movement, the motion. The differentiable position change. You were here, now you're there.

There's only a decernable position change once every 5 frames, you have no idea what's going on in the other 4. If you interpolate the data, all you have is a mathematical estimate of what's happening in these 4 frames.

My physics is not what it should be these days, so feel free to correct me.

 

[metamars]

Yah, but the points. The movement, the motion. The differentiable position change. You were here, now you're there.

There's only a decernable position change once every 5 frames, you have no idea what's going on in the other 4. If you interpolate the data, all you have is a mathematical estimate of what's happening in these 4 frames.

My physics is not what it should be these days, so feel free to correct me.

That's not true for the whole period under consideration. From Dave's table, between 3.0 and 3.17 sec you have ~ 10 feet of displacement. That's about 11.36 pixels worth. So, I expect you'll have a discernible position change visible in each frame, .034 sec apart.

At the 1 sec mark, which is near where the jolt is considered to occur, it's more like 4.7 meters of drop over .17 seconds. That's still 5.3 pixels worth. I don't want to figure it out, but I'll guess that at least 3 of the .034 sec frames in this interval have different location pixels showing.


When you consider the displacement to be monotonic, I intuitively expect that you can make some sort of statistically valid statement about where the displacement is in any particular pixel. E.g., in the paragraph above, I guessed (reasonably, I trust) that in the frames spanning 3 < t < 3.17 seconds, 2 pairs will show duplicate displacement/pixel values, and the 5th frame will have a 3rd distinct value. From monotonicity, you can say (again, in some statistical sense that I don't have sufficient knowledge of to express well) that displacement in the earlier frame of a duplicate pair is actually less than the one that occurs in the later frame, even if you don't know exactly what it is.

This is not the same as saying "you have no idea what the displacement is within .88 feet". E.g., if you assume that the positions are exactly the same, then you will have had an infinite deceleration over an infinitesimally small duration of time. How likely is that? Not very.

 

[metamars]

bad physics

Yipes, I see what Szamboti and MacQueen did. (It would have helped if I had actually read subsequent posts on the thread I started, and linked to, earlier.)

Tony says

Use the equations I provide in the paper and do the math at each increment. You will find that if you calculate what the acceleration is at 1.50, 1.67, and 1.83 seconds (using a = 2d/t**2) it is 22.684 ft./sec/sec at 1.50 seconds, 23.350 ft./sec/sec at 1.67 seconds, and 23.124 ft./sec/sec at 1.83 seconds.

This is not self-consistent, because a = 2d/t**2 only holds if a is constant. But Tony's own computed values for acceleration are variable, which is a contradiction.

IMO, this is a serious enough error that either the paper should be withdrawn, or a correction published. I still think something useful regarding the 31g jolt hypothesis could be determined from a careful analysis, so hopefully somebody will pursue this. But this particular paper doesn't come up to snuff.

 

[R.Mackey]

This is not self-consistent, because a = 2d/t**2 only holds if a is constant. But Tony's own computed values for acceleration are variable, which is a contradiction.

Yes, good on you and nice discussion over there (Drs. Greening and Benson, among others, contributing to the dogpile).

Also, as they point out -- much like I did here -- even with infinite resolution, I wouldn't expect to see much of an initial jolt. The collapse initiation is gradual, the impact isn't square, and the upper block is a somewhat flexible object. Again, all this paper refutes is a non-essential simplification in Bazant & Zhou's original model, one that has no impact on their conclusion.

What will be instructive next is just how long Mr. Szamboti holds out before admitting his error, if ever. Or one from Dr. Jones that, perhaps, he should have listened to his reviewers instead of his dogma. I'm guessing never, but maybe even they can learn...

 

[Heiwa]

I like this observation by McQueen/Szamboti:

"What happened to RB-12+ (the upper part -floors 98-roof) during its fall? It would appear, based on the Sauret video and other video recordings of the event, that a substantial portion of the bottom part of RB-12+ (the upper part), along with DS-6 (floors 92-98), was violently destroyed amidst clouds of ejected matter at the same time the top portion of RB-12+ (the upper part) containing roof top was falling. Since the clouds of matter in the videos partially obscure the details of the event, it is easy to see why someone might hypothesize that the fall of the upper portion of the rigid block was accompanied by a fall of its lower portion. But we do not see a fall of its lower portion: we simply see violent destruction in the vicinity of the lower portion and fall of the upper portion."

Thus - the upper part is physically destroyed prior any destruction takes place below floor 92. Any child can see it on all videos.

But what destroys the upper part before collapse of floor 92 and below? Release of potential energy? Where does it come from? The roof structure? The hat truss. Very little potential energy there!

In my simple view what destroys the upper part later also destroys the structure below floor 92. Guess what?

 

[funk de fino]

I like this observation by McQueen/Szamboti:

"What happened to RB-12+ (the upper part -floors 98-roof) during its fall? It would appear, based on the Sauret video and other video recordings of the event, that a substantial portion of the bottom part of RB-12+ (the upper part), along with DS-6 (floors 92-98), was violently destroyed amidst clouds of ejected matter at the same time the top portion of RB-12+ (the upper part) containing roof top was falling. Since the clouds of matter in the videos partially obscure the details of the event, it is easy to see why someone might hypothesize that the fall of the upper portion of the rigid block was accompanied by a fall of its lower portion. But we do not see a fall of its lower portion: we simply see violent destruction in the vicinity of the lower portion and fall of the upper portion."

Thus - the upper part is physically destroyed prior any destruction takes place below floor 92. Any child can see it on all videos.

But what destroys the upper part before collapse of floor 92 and below? Release of potential energy? Where does it come from? The roof structure? The hat truss. Very little potential energy there!

In my simple view what destroys the upper part later also destroys the structure below floor 92. Guess what?

Will you please go back the the kiddies threads and stop spoiling this one with your lies?

 

[Dave Rogers]

You didn't reproduce it, you approximated it. And it's a rather poor approximation at t = .17s and .83 sec, where your average acceleration is not only much more than the (smoothed) acceleration that Szamboti MacQean calculated, but even more than G!

Just to clarify, when I say I've reproduced it myself, I'm referring to calculations that I didn't put on the forum. The only work I've posted here is the application of MacQueen and Szamboti's analysis technique to a synthesised dataset which included a 31g deceleration. I wouldn't be surprised at physically unreasonable results from that technique, as it doesn't calculate the true velocity.

I've had a similar experience... Mr. Szamboti sent me some PM's, but basically claimed that I was "obviously rattled" in my response.

At least he's been decent enough only to vilify me in public.

Dave

 

[beachnut]

Yipes, I see what Szamboti and MacQueen did. (It would have helped if I had actually read subsequent posts on the thread I started, and linked to, earlier.)

Tony says



This is not self-consistent, because a = 2d/t**2 only holds if a is constant. But Tony's own computed values for acceleration are variable, which is a contradiction.

IMO, this is a serious enough error that either the paper should be withdrawn, or a correction published. I still think something useful regarding the 31g jolt hypothesis could be determined from a careful analysis, so hopefully somebody will pursue this. But this particular paper doesn't come up to snuff.

No you can't see the 31G jolt because there is not enough resolution in time and space. You have 33 ms frames, you need 1 ms frames, you have 0.88 foot pixels, you need 1 inch pixels.

So all we need is a 1000 frame/second, and 1-inch resolution.

 

[Furcifer]

Also, as they point out -- much like I did here -- even with infinite resolution, I wouldn't expect to see much of an initial jolt. The collapse initiation is gradual, the impact isn't square, and the upper block is a somewhat flexible object.

I'm not sure if I agree with this. While infinite resolution is certainly "ideal" there would be a point, some point, where things "let loose" and could be observed. Much like a rubber band stretched to the limits, steel gives way in a sudden "jolt". Due to the nature of the WTC design, I think there would be much more to be observed in the rotation of the upper block than the linear motion. Im just saying if I was going to waste time I'd focus on the torque rather than the "fall". The asymmetrical nature of the fires and hole suggests this.

 

[HENTAI DOUKYUSEI JP]

You EVER gonna take a position on anything, or simply continue being 911 Blogger's waterboy?

It is my understanding he IS their paperboy.
Whenever Twoofer "leaders" need something destroyed, he eats it.

 

[Dave Rogers]

I think this paper is pretty much disposed of now. There's just one point I'd like to return to.

I still think something useful regarding the 31g jolt hypothesis could be determined from a careful analysis, so hopefully somebody will pursue this.

One question: what 31g jolt hypothesis?

Bazant and Zhou calculate a 31x dynamic loading, and comment that the lower structure cannot conceivably be strong enough to support such a loading. In other words, it would take a 31g deceleration to arrest the fall within the elastic limit of the structure, whereas the lower structure would only be expected to be capable of about a 3g deceleration assuming a typical safety factor of 3. Therefore, as I understand it, Bazant and Zhou's claim is that the upper block did not experience a 31g deceleration. This has been precisely inverted by MacQueen and Szamboti to a claim that the upper block did experience a 31g deceleration.

Bazant and Zhou also state that:

For our purpose, we may assume that all the impact forces go

into the columns and are distributed among them equally. Unlikely
though such a distribution may be, it is nevertheless the
most optimistic hypothesis to make because the resistance of the
building to the impact is, for such a distribution, the highest. If the
building is found to fail under a uniform distribution of the impact​

forces, it would fail under any other distribution.

In other words, they are not stating that a single impact occurred; they are, as Ryan Mackey on this forum and Frank Greening on the 9/11 Forum (among others) have pointed out, presenting a limiting case biased towards survival. If collapse propagates in the limiting case, it will propagate in general. They aren't arguing that a single impact actually occurred. Therefore even a 3g jolt is not required in either NIST or B&Z's description of collapse.

So: What 31g jolt hypothesis?

Dave

 

[beachnut]

I think this paper is pretty much disposed of now. There's just one point I'd like to return to.


...
So: What 31g jolt hypothesis?

Dave

If they get to that, where did they get 13 ms from.

I assume they had the 31 G thing, but to get 31 G at the first impact you would have about 2.15 ms event. But the paper is woo, the 911Truth cult members have no clue why.

 

[The Big Dog]

I thought I'd bump this thread.

It appears that our intrepid authors have withdrawn their original paper and posted a new one. I notice the link is now dated January 21, 2009, which is about a week after Red Ibis loaded the paper in his bag, got on his bike and dropped it in our midst.

Hell if I can see a disclosure that this is a revised paper, not that I looked to hard.

 

[RedIbis]

I thought I'd bump this thread.

It appears that our intrepid authors have withdrawn their original paper and posted a new one. I notice the link is now dated January 21, 2009, which is about a week after Red Ibis loaded the paper in his bag, got on his bike and dropped it in our midst.

Hell if I can see a disclosure that this is a revised paper, not that I looked to hard.

I don't have the info in front of me because I'm not at home, but I believe they corrected some of their figures. How horrible that they would admit an error and then correct it. From what I recall the corrections don't affect the conclusions.

 

[dtugg]

From what I recall the corrections don't affect the conclusions.

In other words, it is still horse manure.

 

[The Big Dog]

I don't have the info in front of me because I'm not at home, but I believe they corrected some of their figures. How horrible that they would admit an error and then correct it. From what I recall the corrections don't affect the conclusions.

Dear Lord, did RedIbis just make a claim that can be verified?? In fact, he made two: 1. that our intrepid authors admitted an error; 2. they corrected that error.

I'll skip the second point because "you don't have the info in front of me." So we'll dig into the first verifiable claim: can you kindly provide a link to where they disclosed that they withdrew their first paper and substituted this new paper?? I simply don't see it.

 

[DGM]

I'd like to know how it made it through the Jones' rigorous peer-review in the first place.

 

[R.Mackey]

I don't have the info in front of me because I'm not at home, but I believe they corrected some of their figures. How horrible that they would admit an error and then correct it. From what I recall the corrections don't affect the conclusions.

But this proves three things:

1. The "peer-review" at the JONES is inadequate;
2. Our analysis of their work is better than theirs is, including that of the authors; and
3. The authors are still wrong, since they fail to understand (or deliberately misrepresent) the proper inference.​

As I explained before, and is summarized very neatly elsewhere, even if the math was all done correctly, and gave you the same answers, the interpretation is still wrong. What they would prove, in this unlikely event, is that the "best case" situation of Bazant & Zhou did not happen. The non-existence of a "Big Jerk" does not mean the structure would not have collapsed without a nefarious and unseen agent. It means that the collapse was not started with a simultaneous, axial impact as the upper block fell squarely and rigidly on the lower portion.

Again, we already know this. We know the collapse started as a tilt, and we know this is even harder for the lower portion to resist. Bazant & Zhou present the best case, and show that even the best case leads to a collapse. Mr. Szamboti and his silent partner have actually shown that the best case was far too optimistic, which we always suspected. Yet, incredibly, they claim this means the collapse shouldn't have happened at all.

Even more incredibly, you're still a willing, proud dupe.

By issuing an un-announced "correction" that still misses the central point, I can only assume they are stringing the likes of you along. The change is an admission that they're incompetent. The part they didn't change is a fascinating example of Irreducible Delusion -- where all data leads to the same conclusion. And you're a sucker for it.