Debate! What debate?
- Thread starter Apollo20
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LashL
Goddess of Legaltainment™
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Absolutely no apologies necessary, OMGturt1es. It is often very difficult to tell satire from genuine troofer lunacy for precisely the reasons you set out.
People with brains in their heads can research his claims and verify them for themselves.
So he is kind of saying the oposite of what you claimed he said and you call it a case of: "my wording was unclear"?
So a pillar of expanding smoke is an energy sink? A cloud of dust after collapse is an energy sink?
Just hypothetically Ace, what do you think these things would look like if the building was burning and then collapsed the way NIST said it did?
Would the smoke not expand as it rose?
What would the dust cloud have looked like?
If your idea of delightful includes spending all day with an egomaniacal loony.
Horatius
NWO Kitty Wrangler
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So your interpretation of text is just as bad as your interpretation of photos and video. Check. Colour me surprised.
As for "unclear wording":
Where in his quoted passage does he "admit it was wrong"? What I see is Dr. Greening attempting to explain to you the same thing we've tried to explain for all these months: Mathematical models by there nature tend to be simplification of reality, as real reality is far to complex to be modeled accurately in any reasonable fashion. Those approximations can still provide useful analysis, if used with care and attention.
Your continued resistance to understanding this basic fact of physics and math is one of the main reasons you will never understand science.
TruthSeeker1234
Banned
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Here's what the Greening admission boils down to:
1. I accuse him of making false assumptions.
2. He doesn't deny making false assumtions, instead he moves the goalpost and says that his assumptions don't need to be true.
That, to me, is a clear admission that the assumptions in question are false.
Can we not all agree that Dr. Greening's assumptions about the "intact block" are false assumptions?
1. I accuse him of making false assumptions.
2. He doesn't deny making false assumtions, instead he moves the goalpost and says that his assumptions don't need to be true.
That, to me, is a clear admission that the assumptions in question are false.
Can we not all agree that Dr. Greening's assumptions about the "intact block" are false assumptions?
Horatius
NWO Kitty Wrangler
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He doesn't "move the goalposts". He explains the nature of modeling.
Figure it out, for fracs sake!
No they are not "false". They are approximations. They are limiting assumptions made openly, with the clearly expressed intent to make the calculations simpler, or even possible. They are entirely consistent with normal practices in the sciences, and physics in particular. If someone who actually knows what they're talking about disagrees with his limiting assumptions, they are free to replicate his work with their own set of assumptions, in an attempt to show their assumptions are a better model of reality than his. So get to work, or STFU.
Don't you think it's just the least bit odd that the just about the only people who complain about these alledgely "false" assumptions (other than Judy Wood, who is clearly crazy) are not trained scientists or engineers? That's because those of us who have actually studied actual science have seen just such calculations made in a myriad of different calculations.
The only difference between those calculations and Dr. Greening's calculations is, there are no crazy CTists insisting on attaching some sinister motivation to them. Probably because no Ctist has ever studied enough physics to even know about such calculations.
Figure it the frac out!
jaydeehess
Penultimate Amazing
That is one very odd statement coming from a guy who believes in a no-plane/DEW senario.
Will you show us Wood's calculations on the output power and beam type or would that just get things bogged down with numbers?
Greening is admitting no more 'wrong' than it would be to say that Newton was 'wrong'(not that I am saying that Greening is comparable to Newton). Einstein made adjustments to Newtons formulas but Newton was not 'wrong'.
Greening has merely stated that further honing of the assumptions show, by way of calculation, that the conclusions arrived at via his first approximation still hold.
What part of that do you not understand?(my guess, all of it)
jaydeehess
Penultimate Amazing
other cases in point.
In a multiple body system assuming the mass of each body to be a point mass at the center of each body.
In electronic circuit design, assuming a zero, base-collector capacitance.
In short distance signal transmission assuming no transmission losses or phase changes.
Foolmewunz
Grammar Resistance Leader, TLA Dictator
Ace, in the real world "No" doesn't mean "Yes". They taught you that in sensitivity training, didn't they?
The man never admitted to what you said he did, and you claimed you had evidence to prove it. Your evidence, like your logic, is crap.
Be a man. You were wrong/you blatantly lied! Suck it up, move on, go see a doctor then man the barricades.
The man never admitted to what you said he did, and you claimed you had evidence to prove it. Your evidence, like your logic, is crap.
Be a man. You were wrong/you blatantly lied! Suck it up, move on, go see a doctor then man the barricades.
Horatius
NWO Kitty Wrangler
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Just the sort of thing I was thinking of. Other examples:
The small angle aproximation sin(theta) = Theta, cos(theta) = 1. Used in calculating the period of a pendulum, in simple harmonic motion, as well as other areas.
Or the classic massless string, again used in pendulum calculations, among others.
Or, the classic beloved of all the twoofers, Gravitational Potential Energy, which assumes the acceleration due to gravity is constant as the masses move closer or farther apart, which of course is wrong. But close enough for a reasonable approximation.
Or hey, how about a pseudo or "fictitious" centrifugal force which appears when a rotating reference frame is used for analysis. They even admit openly that it's "Fictitious"!
Heck, those darn scienticians even have fancy names for how closely they approximate things!
And let's throw a little math on the fire, with the linear approximation.
Heck, even Newton's (he of F=ma, another twoofers fave!), laws are just approximations:
So, Ace, when can we expect to see you out harassing all these other scientists for their "false" assumptions? Because it looks to me like the entire basis of our modern understanding of the universe is built on the same shaky ground as Dr. Greening's collapse calculations! You have to save us from all this!
That is, unless you're willing to admit that maybe, just maybe, the science guys might know what they're doing?
Nah, that's just crazy talk........
And just in case you think it's only the normal scientists who make assumptions and approximations, go take a look at your lady loves' site:
How many assumptions and approximations is that? And every single one of them with absolutely no justification, and in several cases, demonstratably wrong.
Also note the implicit assumptions, that aren't even acknowledged:
(1/20)x(207/5280)2x(1368x12 inches)
No adjustment for the different densities of dust vs. solid material? !?!?
And she tries to get that one past us under the radar? And you think this makes her more reliable than Dr. Greening?
And that doesn't even get into the flat out mistake she makes, when at the last step of her "calculation", she goes from one tower to two, without multiplying by two! And you would have us follow her, rather than anyone else at all?
Foolmewunz
Grammar Resistance Leader, TLA Dictator
Hey! They told me there wouldn't be any math!
Will this still be graded on a curve?
Will this still be graded on a curve?
Disbelief
Illuminator
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Ace, would an example of modelling for something you deal with daily help? Since you seem to think that they can model something this complex easily, it would be no problem to model a car crash and to do so repeatedly for a wide variety of accidents. Even large SUVS only have a few thousand parts and welds, so this should be fairly simple.
Now, would you trust your life to a vehicle that was only modelled on the tube? Would you really believe that a computer would be able to take into account everything? Even the best engineers in the worlld can not tell you exactly how to model a car crash, so how do you think they can do every tiny detail of the WTC?
Now, would you trust your life to a vehicle that was only modelled on the tube? Would you really believe that a computer would be able to take into account everything? Even the best engineers in the worlld can not tell you exactly how to model a car crash, so how do you think they can do every tiny detail of the WTC?
Horatius
NWO Kitty Wrangler
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Confessions of a 9/11 Agnostic
My name is Frank Greening/Neu-Fonze/Apollo20. I have observed a lot of mixed reaction to my recent contributions to PhysOrg and JREF forums. I am therefore posting the following material to explain who I am and where I’m coming from…..
First a little history:
I worked for 23 years as a research scientist for the large nuclear electric utility OPG and became involved in the study of hydrogen embrittlement of zirconium pressure tubes. This was a major problem and concern for AECL, the designer of the CANDU reactor. AECL needed to explain to our nuclear regulator why so much hydrogen was entering the pressure tubes in the 500 MW Units at Pickering. AECL proposed a THEORY that made no sense to me. I spent 5 years studying real samples of highly radioactive tubing and found lots of evidence that AECL’s theory was plain WRONG! I presented my results at a number of meetings and was essentially shouted down. I did more research and found to my horror that one of my colleagues was cooking up data at a well-known Canadian University to support the dubious AECL theory. I approached a post-doc at the University who I could trust and together we checked the computer code being used to generate the data and found the steps in the program where the “fudging” was being covertly carried out. I tried to expose this deception and was blocked at every turn. I was barred from speaking to or corresponding with zirconium experts at ASTM who had published the fudged data. I was barred from submitting an article, correcting the fudged data, to a journal. I was threatened with a lawsuit by a professor even though I had a letter from the same professor admitting that data had been falsified. After battling “the system” for 5 years I took early retirement out of frustration and disgust with the state of science in industry and academia here in Canada.
My 9/11 Research:
About 2 years after my early retirement I began researching 9/11 and became fascinated by the collapse of WTC 1 & 2. I realized that it would be of great interest to calculate the collapse times for a gravity driven collapse and compare the result with observations. This I did, and wrote up my findings in the “Energy Transfer” article that was subsequently posted on the 911Myths website. I was quite surprised at the response to my work: the calculations were well received by some but scorned by others.
The model I based my calculation on was indeed quite crude, so I have endeavored to improve it by including the effects of variable column strength and mass shedding. I tested the improved model and found that the towers always exhibited a self-sustaining collapse for realistic values of the various input parameters. Nevertheless, while my model appeared to show that a gravity driven collapse of the Twin Towers was physically possible, I still had some doubts about collapse initiation. These doubts stemmed from the fact that my model assumes that the upper block of floors above the impact zone descends one storey under free fall, thereby providing more than enough energy to destroy the columns supporting the floor below and initiate a progressive collapse.
But did the collapse of each tower really begin with such a single floor failure? I studied the appropriate sections of the NIST Report seeking an answer to this question. It soon became apparent that the tipping of the upper section of each tower was a key feature of the collapse. Thus I began studying the tipping of WTC 1 & 2 and ultimately wrote two articles on this topic that were posted on 911Myths.
The research described in these articles showed that WTC 1 required almost 2 meters of downward displacement in the upper section of the building to initiate collapse. This is about two times the downward displacement required for the collapse of WTC 2, and six times NIST’s estimate of Dd(WTC 2) of about 30 cm based on its finite element computer model. In contrast, a simple energy analysis of the collapse shows that NIST’s small downward displacements lead to inferred collapse energies that are too low to be acceptable – we know the Twin Towers would not collapse that easily. Further, the geometry of a “Leaning WTC Tower” with an asymmetric downward displacement of 30 cm implies a tilt angle of less than ½ degree. Remarkably, however, NIST suggest that tilt angles before collapse initiation were more than 4° for WTC 1 & 2. Thus the NIST Final Report first underestimates the downward displacements within the Twin Towers, only to later overestimate the initial tilt angles to justify the collapse.
A close look at the failure of WTC 2 shows that the collapse began with a tilting or rotational motion of the upper section of the Tower about a “hinge” at the 80th floor. This rotational motion, which commenced at a tilt angle ~ 2°, was caused by an almost instantaneous multi-column failure that eliminated the structural support on one side of WTC 2 near the impact zone. Once set in motion, the upper block moved with a nearly “free” rotational trajectory of a body pivoting under the constant force of gravity. This behavior was sustained at tilt angles up to about 20°. Thereafter the motion of the block changed somewhat although the suggestion that the tilting suddenly stopped is not correct. What appears to happen is that the upper section was continuously crushed near the 80th floor by its own momentum so that the rotation was no longer that of a rigid body. Eventually the "hinge" at the northeast corner failed and the descending block took on a more vertical motion. Interestingly, once the hinge failed, and the pivot became frictionless, the motion of the center of gravity is predicted to become vertical, causing a shift in the rotational axis, as observed.
For most of 2006 I switched my attention to two important aspects of the collapse of WTC 1 & 2: the pulverization of concrete and the sustained high temperatures of the rubble pile. First, I carried out an energy balance analysis of the collapse of WTC 1 that included the energy consumed in crushing concrete on one floor (234 MJ) and compared this to other contributions to the energy dissipated by the collapse. As expected, the plastic strain energy dissipated by the buckling of columns (284 MJ) was confirmed to be the largest drain on the kinetic energy driving the collapse, but the energy to pulverize the concrete was clearly an important additional energy sink. However, I also concluded that such energy sinks should be summed over two WTC floors per impact to allow for the simultaneous destruction of the uppermost floor of the lower fixed section, and the lowest floor of the descending section. Such an assumption leads to an energy decrement that still assures a self-sustaining progressive collapse of WTC 1 if the input kinetic energy is derived from a one-storey free fall of the upper block- a condition that must be modified in a tipping scenario.
The sustained high temperatures of the rubble pile proved to be more problematic. The NIST Report indicates that about 100 tonnes of burning material and smoldering “embers”, at 500 - 700° C, fell into the rubble pile when the Twin Towers collapsed. Propagation of smoldering combustion within the rubble pile was sustained by the indigenous supply of live load “fuel”- consisting of office furniture, paper, textiles and plastic materials - and oxygen. Setting aside the issue of oxygen availability, let us consider how long the available fuel could last. The heat flux of a smoldering fire is typically ~ 8 kW/m2 from which we may calculate the average fuel consumption rate within the rubble pile. NIST estimate that there was initially about 50,000 kg of combustible material on each floor of WTC 1 & 2. If we assume that material from about 5 floors was consumed before the Towers collapsed, about 5,250,000 kg of “fuel” was initially available within the rubble from each Tower. It is a simple matter to show that this fuel would be able to sustain the rubble pile fires for no more than about 30 days. However, it was not until December 19th 2001, or 100 days after 9/11, that the Governor of New York, George Pataki, officially declared the WTC fires to be totally extinguished. We are left wondering what “stoked” the rubble pile fires beyond the expected 30 days.
Thus, by the start of 2007, I still had plenty of questions about the official version of the collapse of the Twin Towers. And this is essentially where I stand today. Unlike the self-assured posters on PhysOrg and JREF who claim to KNOW what happened to the Twin Towers, I remain a 9/11 agnostic.
And as a scientist I believe there is always room for doubt and for more research. In fact, that’s how I see research – a process of re-searching, of looking again. The NIST Report is a great start, but only that. It leaves some unanswered questions. It may satisfy the Arthurs (on PhysOrg) and the Gravys (on JREF) of this world, but not me. And my work experience in the Canadian nuclear industry has taught me to be skeptical of the “official” view - the consensus view - because it is usually politically motivated!
Finally, about my AP theory – it’s just that, a theory – but one that I believe is better than the current selection being offered by the conspiracy theorists. Sooner or later it will be replaced by another, and another, but unlike G. W. Bush, I am not bothered by “outrageous” theories…..
I’M ON THE ROAD TO FIND OUT
Cat Stevens
My name is Frank Greening/Neu-Fonze/Apollo20. I have observed a lot of mixed reaction to my recent contributions to PhysOrg and JREF forums. I am therefore posting the following material to explain who I am and where I’m coming from…..
First a little history:
I worked for 23 years as a research scientist for the large nuclear electric utility OPG and became involved in the study of hydrogen embrittlement of zirconium pressure tubes. This was a major problem and concern for AECL, the designer of the CANDU reactor. AECL needed to explain to our nuclear regulator why so much hydrogen was entering the pressure tubes in the 500 MW Units at Pickering. AECL proposed a THEORY that made no sense to me. I spent 5 years studying real samples of highly radioactive tubing and found lots of evidence that AECL’s theory was plain WRONG! I presented my results at a number of meetings and was essentially shouted down. I did more research and found to my horror that one of my colleagues was cooking up data at a well-known Canadian University to support the dubious AECL theory. I approached a post-doc at the University who I could trust and together we checked the computer code being used to generate the data and found the steps in the program where the “fudging” was being covertly carried out. I tried to expose this deception and was blocked at every turn. I was barred from speaking to or corresponding with zirconium experts at ASTM who had published the fudged data. I was barred from submitting an article, correcting the fudged data, to a journal. I was threatened with a lawsuit by a professor even though I had a letter from the same professor admitting that data had been falsified. After battling “the system” for 5 years I took early retirement out of frustration and disgust with the state of science in industry and academia here in Canada.
My 9/11 Research:
About 2 years after my early retirement I began researching 9/11 and became fascinated by the collapse of WTC 1 & 2. I realized that it would be of great interest to calculate the collapse times for a gravity driven collapse and compare the result with observations. This I did, and wrote up my findings in the “Energy Transfer” article that was subsequently posted on the 911Myths website. I was quite surprised at the response to my work: the calculations were well received by some but scorned by others.
The model I based my calculation on was indeed quite crude, so I have endeavored to improve it by including the effects of variable column strength and mass shedding. I tested the improved model and found that the towers always exhibited a self-sustaining collapse for realistic values of the various input parameters. Nevertheless, while my model appeared to show that a gravity driven collapse of the Twin Towers was physically possible, I still had some doubts about collapse initiation. These doubts stemmed from the fact that my model assumes that the upper block of floors above the impact zone descends one storey under free fall, thereby providing more than enough energy to destroy the columns supporting the floor below and initiate a progressive collapse.
But did the collapse of each tower really begin with such a single floor failure? I studied the appropriate sections of the NIST Report seeking an answer to this question. It soon became apparent that the tipping of the upper section of each tower was a key feature of the collapse. Thus I began studying the tipping of WTC 1 & 2 and ultimately wrote two articles on this topic that were posted on 911Myths.
The research described in these articles showed that WTC 1 required almost 2 meters of downward displacement in the upper section of the building to initiate collapse. This is about two times the downward displacement required for the collapse of WTC 2, and six times NIST’s estimate of Dd(WTC 2) of about 30 cm based on its finite element computer model. In contrast, a simple energy analysis of the collapse shows that NIST’s small downward displacements lead to inferred collapse energies that are too low to be acceptable – we know the Twin Towers would not collapse that easily. Further, the geometry of a “Leaning WTC Tower” with an asymmetric downward displacement of 30 cm implies a tilt angle of less than ½ degree. Remarkably, however, NIST suggest that tilt angles before collapse initiation were more than 4° for WTC 1 & 2. Thus the NIST Final Report first underestimates the downward displacements within the Twin Towers, only to later overestimate the initial tilt angles to justify the collapse.
A close look at the failure of WTC 2 shows that the collapse began with a tilting or rotational motion of the upper section of the Tower about a “hinge” at the 80th floor. This rotational motion, which commenced at a tilt angle ~ 2°, was caused by an almost instantaneous multi-column failure that eliminated the structural support on one side of WTC 2 near the impact zone. Once set in motion, the upper block moved with a nearly “free” rotational trajectory of a body pivoting under the constant force of gravity. This behavior was sustained at tilt angles up to about 20°. Thereafter the motion of the block changed somewhat although the suggestion that the tilting suddenly stopped is not correct. What appears to happen is that the upper section was continuously crushed near the 80th floor by its own momentum so that the rotation was no longer that of a rigid body. Eventually the "hinge" at the northeast corner failed and the descending block took on a more vertical motion. Interestingly, once the hinge failed, and the pivot became frictionless, the motion of the center of gravity is predicted to become vertical, causing a shift in the rotational axis, as observed.
For most of 2006 I switched my attention to two important aspects of the collapse of WTC 1 & 2: the pulverization of concrete and the sustained high temperatures of the rubble pile. First, I carried out an energy balance analysis of the collapse of WTC 1 that included the energy consumed in crushing concrete on one floor (234 MJ) and compared this to other contributions to the energy dissipated by the collapse. As expected, the plastic strain energy dissipated by the buckling of columns (284 MJ) was confirmed to be the largest drain on the kinetic energy driving the collapse, but the energy to pulverize the concrete was clearly an important additional energy sink. However, I also concluded that such energy sinks should be summed over two WTC floors per impact to allow for the simultaneous destruction of the uppermost floor of the lower fixed section, and the lowest floor of the descending section. Such an assumption leads to an energy decrement that still assures a self-sustaining progressive collapse of WTC 1 if the input kinetic energy is derived from a one-storey free fall of the upper block- a condition that must be modified in a tipping scenario.
The sustained high temperatures of the rubble pile proved to be more problematic. The NIST Report indicates that about 100 tonnes of burning material and smoldering “embers”, at 500 - 700° C, fell into the rubble pile when the Twin Towers collapsed. Propagation of smoldering combustion within the rubble pile was sustained by the indigenous supply of live load “fuel”- consisting of office furniture, paper, textiles and plastic materials - and oxygen. Setting aside the issue of oxygen availability, let us consider how long the available fuel could last. The heat flux of a smoldering fire is typically ~ 8 kW/m2 from which we may calculate the average fuel consumption rate within the rubble pile. NIST estimate that there was initially about 50,000 kg of combustible material on each floor of WTC 1 & 2. If we assume that material from about 5 floors was consumed before the Towers collapsed, about 5,250,000 kg of “fuel” was initially available within the rubble from each Tower. It is a simple matter to show that this fuel would be able to sustain the rubble pile fires for no more than about 30 days. However, it was not until December 19th 2001, or 100 days after 9/11, that the Governor of New York, George Pataki, officially declared the WTC fires to be totally extinguished. We are left wondering what “stoked” the rubble pile fires beyond the expected 30 days.
Thus, by the start of 2007, I still had plenty of questions about the official version of the collapse of the Twin Towers. And this is essentially where I stand today. Unlike the self-assured posters on PhysOrg and JREF who claim to KNOW what happened to the Twin Towers, I remain a 9/11 agnostic.
And as a scientist I believe there is always room for doubt and for more research. In fact, that’s how I see research – a process of re-searching, of looking again. The NIST Report is a great start, but only that. It leaves some unanswered questions. It may satisfy the Arthurs (on PhysOrg) and the Gravys (on JREF) of this world, but not me. And my work experience in the Canadian nuclear industry has taught me to be skeptical of the “official” view - the consensus view - because it is usually politically motivated!
Finally, about my AP theory – it’s just that, a theory – but one that I believe is better than the current selection being offered by the conspiracy theorists. Sooner or later it will be replaced by another, and another, but unlike G. W. Bush, I am not bothered by “outrageous” theories…..
I’M ON THE ROAD TO FIND OUT
Cat Stevens
Disbelief
Illuminator
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Very nice post Dr. Greening. I am curious about one thing, will you ever be satisfied with an answer for what happened? I am not saying that we should stop looking at the tower collapse, but is there a point where you would feel comfortable with a theory?
DavidJames
Penultimate Amazing
Dr. Greening:
Welcome to the forum. I'm curious what you think about TruthSeekker1234 and his using your disagreements with the NIST report to to support his CT theory?
My second question is this. I think an scientific based debate over the WTC collapse is healthy. What have you done to work with either your peers or the authors and engineers of NIST to move the debate further?
Welcome to the forum. I'm curious what you think about TruthSeekker1234 and his using your disagreements with the NIST report to to support his CT theory?
My second question is this. I think an scientific based debate over the WTC collapse is healthy. What have you done to work with either your peers or the authors and engineers of NIST to move the debate further?
Last edited:
Crazy Chainsaw
Philosopher
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I do not believe that Apollo20 is referring to anything that has to do with thermate-thermite, and his ideas do have basis what I have seen and done tells me that this is a real possibility in the real physical Universe and something that could have went unobserved by Nist simply over looked.
http://www.cheresources.com/ironfires3.shtml
This is still under research, if you would like to help find out where and when accelerators were used on the concrete to cure it in cold weather, which slabs of concrete were poured in cold conditions.
This is an important discussion because there are other buildings, of similar construction to the twin towers.
I can not say more, at this time.
I believe Dr. Greening is being cautious, because he is now criticized by both sides for simply exploring possibilities, though the scientific method as best he can with his knowledge and his limited resources.
If you wish to criticize me than feel free to do so, I do not give a dam about it, I admit that I may be wrong, but my curiosity got me into this and it will not let me stop now! PS. I hope I am wrong, because if right thousands of lives in future fires could be at risk in similar buildings.
PS. Apollo20 is aware that sono Chemical reactions would effect any thermites-thermates in said twin towers, the likely hood that they could survive the plane crashes is almost 0 probably less.
I think he is proposing a concise cognitive theory, not a CT, he is just trying to add up a few loose ends.
Nist did not have unlimited funding or unlimited time, or a god like ability to view every aspect of the collapses, it was simply good people doing a hard job with what they had. There are always unanswered questions, loose ends, but nothing that needs to be included in loose change final cut.
Curiosity and honnest research, sometimes mean that someone must look at other aspects as possibilities as longs as they are possible in the known reality of the known universe and do not involve invisible elves with invisible explosives.