Qlipoth: Shutting down a hate group
Posted by Qlipoth at 9:41 AM
livingfossil 5:24 PM
"No conservative would ever..."
Yea, they would just like organize an armed militia group and drive back and forth looking for like, running brown people to like, sequester, and maybe like rough up, and stuff. Chanting is for libruls.
brownfemipower 7:42 PM
exactly. that part almost ruins the rest of the tape for me....
Off topic but cockburn's mad as hell and he's not going to take it anymore
Practically a whole issue dedicated to debunking, now I'm no physicist, but you could ask for a real world example of this perfectly reasonable sequence of events and you could ask what happened to wtc7 and you could be forgiven for asking if this guy is a mass pschologist as well.
Billy occam gets exhumed as usual.
Counterpunch vol 13 no 16
Five years after the events of September 11, 2001, conspiracy theories abound as an anxious public seeks to find a comprehensible story for that day and more broadly for their so¬cio-political world. People need reliable foundations upon which to base the many assumptions and conventions they use to carry on their lives.
Half a century ago, public anxiety about the danger of atomic energy and the terror of thermonuclear war exhibited itself in sightings of flying saucers, and a fad of monster movies. C. G. Jung wrote about flying saucer sightings as an instance of “mass psychosis”: a “psychological infection” that spreads among people who lack sufficient understanding to rationalize fearsome political forces and unstable so¬cial conditions (Flying Saucers: A Modern Myth, 1958). Jung was sensitive to any indication that another “psychological epi¬demic” might erupt, as Nazism did, among a population whose government possessed awesome military power. Mass psychosis is a myth held in common, which releases the population from the “normal” restraints of rationality and international social con¬ventions, so they can pursue their mythical vision. The ignorance — and the fears that spring from it as prejudices — of the entranced population is “projected” onto “enemies” whose destruction is sought in the irrational effort to eliminate the actual problem of psychological tensions, (1)
A more entertaining expression of popular anxiety is the monster movie. “Godzilla,” “Rodan,” “Them,” “The Thing” and many others safely frightened viewers with stories of monsters whose
introductions into human society were caused by atomic bomb testing, or were accompanied by radioactivity. For most Americansthe major source of any knowl¬edge of physics is probably this type of motion picture.
The myths we construct to express our understanding of the realities we are im¬mersed in are limited by the range of our knowledge. When the myths are meant to cover over fears about forces beyond our control, they can be conspiracy theories. Consider these pairings of fears and ra¬tionalizations:
* fear of political power/conspiracy theories;
* metaphysical fear (fear of death)/re¬ligion, a theological conspiracy ;
*fear of personal inadequacy/racism,
*fear of strange cultures/ultra-nation¬alism
Certainly, so long as there are more than two people on Earth, conspiracies will occur. But too often we invoke a conspiracy in constructing our story of the world because we lack specific information about the sciences, economics, history and other relevant fields of specialized knowl¬edge. Experience has shown that if the evidence allows for several explanations to a given problem then the hypothesis with the fewest assumptions is most probably correct. This principle is called Occam’s Razor and is attributed to the 14th-century English logician and Franciscan friar Wil¬liam of Ockham (c. 1295–1349) (2).
The events of September 11, 2001, were unsettling for many Americans be¬cause their existing myths were shattered;
these myths had provided comfort and lain undisturbed in consciousness since indoctrination had lodged them there. The increasing power of communications tech¬nology – global telephone networks, the Internet – and the accelerating disregard of subtlety by the elite in its management of public perceptions about government policies has eroded the myths – or illu¬sions – of many Americans. So, trust in government has been broken, fear of its power is vivid, and understanding of the physical mechanisms of Nature is limited. This psychology will naturally sprout conspiracy theories about 9/11.
The reports on the investigations of the collapse of the World Trade Center build¬ings conducted by the National Institute of Standards and Technology (originally the National Bureau of Standards) are to be found at a special NIST website (“NIST & The World Trade Center, Final Report (Sept. 2005),” http://wtc.nist.gov/pubs/#draft (September 11, 2006).
This multi-volume Final Report, issued in September 2005, is the “official word.” There is a vast amount of dry text, much data, descriptive summaries of detailed calculations of the impact ruptures, fires and heating, subsequent deformation, load-shifting, buckling and ultimate fail¬ure of the buildings. NIST addressed the sequence of events and shifting of loads leading up to the failure that allowed the upper blocks to drop; it did not proceed to a detailed simulation of the collapses to the ground. NIST justified this on the grounds that there was sufficient energy in the descending blocks to crush the lower structures, once failures had occurred.
The controlled demolition hypoth¬esis for the collapse of the World Trade Center buildings is described at length in a Wikipedia article (“Controlled demolition hypothesis for the collapse of the World Trade Center”)
The popularity of 9/11 conspiracy theories (also outlined in a useful Wikipe¬dia entry) has prompted NIST to present a very nice webpage addressing the usual questions of the conspiracy viewpoint, and providing clear descriptions in non-techni¬cal English of the physics and engineering explanations embodied in the NIST WTC Towers Final Report .
The World Trade Center Towers (WTC 1, WTC 2) were tall square buildings with supporting columns grouped along the vertical axis (center) and closely spaced along the perimeter (building faces). A “hat truss,” at the top of each building, tied the outer walls to the central columns; and this truss had a height equal to that of five stories.
A hijacked airliner was crashed into each building about 10 or 20 stories down from the top. The columns along one face of the building were sheared for a height of several floors, as were many of the columns at the core. The exploding fuel from the airliner ignited fires throughout the levels within the impact zone, as well as dropping fire down the stairwells and elevator shafts at the building’s core, and billowing up to higher levels. The shocks of impact and detonation loosened the “fire protection” thermal insulation on steel beams in the impact zone.
The damaged core columns in the im¬pact zone could no longer hold up all the weight they were meant to carry. The core columns in the upper block now found it necessary to partially hang from the hat truss. The hat truss pressed down much more forcefully on the perimeter columns, transferring the load of the hanging weight. The added compression of the perimeter columns could only be distributed to the three undamaged faces, and because of the irregularity of the damage one face assumed a much higher load than the other two.
The fuel fire burned up to 1,100 degrees C (2,000 degrees F) for perhaps 10 min¬utes. It ignited the many plastic furnishing (carpets, curtains, furniture, equipment cases, clothing, fixtures, office ceilings and partitions), paper items (paper supplies, books, pressed wood), and some structural elements (gypsum wall boards, plastic plumbing), which then continued the fire. The exposed steel beams in the impact zone heated to between 700 C to 1,000 C. Steel at 700 C has 50 per cent to 70 per cent of its strength at habitable temperatures; and steel at 1,000 C has between 10 per cent to 30 per cent.
The floors in the impact zone sagged because of broken joints to central col¬umns, heat causing their metal framing to soften, weaken and expand; also because of the weight of debris fallen from above . The sagging floors twisted their joints to the perimeter columns (on the three intact faces); the length of column above a floor joint being twisted inward. For one face of the building, the combined stress of the original weight above it, the added com¬pression from the hat truss, and the torque from the sagging floors were too much. Its perimeter beams were bent inward to the point of failure, and they buckled.
The NIST investigation was an ex¬tremely detailed analysis by 200 engineers and building professionals, describing the conditions of the buildings from the instant an airplane collided to the moment a collapse began. The next section of this CounterPunch report carries the story downward from the point where NIST leaves off. NIST concentrated its resources on the greatest uncertainty: what initiated the collapse? It was understood that once an upper block of the building was in mo¬tion the structure below would be unable to counter the dynamic forces, and collapse would proceed to the ground.
Physics Problem Number 1: Free Fall of the WTC Towers
“How could the WTC towers collapse in only 11 seconds (WTC 1) and 9 seconds (WTC 2), speeds that approximate that of a ball dropped from a similar height in vacuum (with no air resistance)?” (NIST FAQ #6)
The suspicion behind this question is that the Towers were weakened by sur¬reptitious, controlled demolitions. In this view, the structure below the impact zone (where airplanes collided, exploded, and fires burned) “should have” provided re¬sistance to the descent of the block above the impact zone, slowing or even stopping the collapse.
The NIST response is that the lower structure was only designed to hold up the weight above any given floor statically, not dynamically. The force imparted by the collision of the upper block was beyond the limits of the lower structure to resist. The lower structure was essentially crumbled by a “hammer” of descending material, and the mass of this hammer increased during the course of the collapse.
Problem 1, Force Balance
Once the framing in the impact zone has failed, the upper block is accelerated by gravity until it crashes into the lower structure below the impact zone. Labeling the mass of the upper block m, and its speed v, the block would have a momen¬tum m*v and an energy of (1/2)*m*v^2. Its weight would be m*g, where g is the constant of gravitational acceleration (9.81 meters/second^2).
The balance of forces on the upper block as it impacts the lower structure is presented here as the impulse momentum form of Newton’s 2nd Law:
Here, positive direction, velocity and force are taken to be vertically upward; dt is a label for “delta t”, a very brief time in¬terval during which the impact occurs and the momentum changes from m*v(initial) to m*v(final); and F is the force of resist¬ance by the lower structure. If A is the net horizontal cross-sectional area of the load-bearing columns of the lower structure, then F/A is the average compressive stress across that area.
When an upper block drops through an impact zone that has lost structural strength, and crashes into the rigid lower structure, it imparts a dynamic force in ad¬dition to its weight. The dynamic force is the second term in the last expression for F. The total force, F, acts during the time interval dt during which the momentum of the upper block is reduced (in magnitude) from m*v(initial) to m*v(final). Clearly, the lower structure will crumble when F is greater than the maximum force it can support, or when F/A is greater than the maximum stress it can withstand.
Problem 1, Numerical Example of Progressive Collapse
v(t) = -g*t, (negative sign for down¬ward direction),
What actually happened in the build¬ings? We consider a suggestive numerical example.
We will assume these floor structures to be dL = 1 meter thick (1 meter = 3.28 feet). Each floor structure is a framework of steel below and within a layer of con¬crete. The floors spanned a distance of between 10 m and 20 m between the outer square perimeter (63.4 m a side) and the core support along the axis of the building, which housed elevator shafts, stairwells and support columns, within a rectangular area of [42 m x 27 m].
The waves alert the volume of the floor structure to the imposition of a new load, and infuse that volume with much higher stress. The floor structure is deflected downward a distance d = -0.077 meters (3 inches) during impact. In becoming stressed, the floor structure absorbs some of the energy of the descending block, slow¬ing it by dv = 0.5 m/s (in this example). Within dt = 1/100 s, the floor structure has transmitted the force of the new load to its joints with the building’s core and periphery.
Problem 1, Wave Trains and Stress Concentration
Elastic waves are launched from the collapse front (the leading edge of de¬scending material, like “weather front”) at the moment of first impact. Within 0.01 s, a stress wave has traveled through the metal framework to five levels below the collapse front, a distance of 20 m. These gation showed conclusively that the failure of the inwardly bowed perimeter columns initiated collapse and that the occurrence of this inward bowing required the sagging floors to remain connected to the columns to pull the columns inwards. Thus, the floors did not fail progressively to cause a pancaking phenomenon.”
For a shot from the hip two days after the collapse, Bazant did pretty well. But, after the NIST legion did all the neces¬sary homework, we now have an accurate result. NIST shows pictures of the inward buckle of the perimeter wall, taken from a police helicopter. Pancaking versus NIST is a nonexistent technical argument only to be found in the imagination of some conspiracy-minded people. The technical community migrated from early hypoth¬eses of the initiation, like pancaking, to the NIST conclusions as a consequence of doing the hard work required. And, there was always unanimity on what drove the collapse once it was initiated: excess dynamic force produced from the gravi¬tational potential energy contained within even one level spacing. Once the top began to fall, it was going to crush the building below it, regardless.
The Absurdity of “Controlled Demo¬lition” (Red Herring #2)
Pierre Sprey is CounterPunch’s techni¬cal reviewer of this report. His comments about the controlled demolition hypothesis are so cogent that I include them here.
“There is not the slightest need to postulate pre-placed explosive charges to explain why the towers collapsed at near free fall speeds. Let me note a few practical aspects of explosive demolitions that make the explosive charge hypothesis improb¬able to the point of absurdity:
“1. Any demolitions expert concocting a plan to hit a tall building with an airplane and then use pre-placed explosives to UN¬DETECTABLY ensure the collapse of the building would never place the explosives 20, 30 and 60 floors below the impact point. Obviously, he would put the explosives on one or more floors as close as possible to the planned impact level.
“2. It is inconceivable that our demoli¬tions expert would time his surreptitious explosions to occur HOURS after the aircraft impact. He couldn’t possibly be absolutely certain that the impact fires would even last an hour. Quite the oppo¬site: to mask the booster explosions, he’d time them to follow right on the heels of the impact.
“3. To ensure collapse of a major build¬ing requires very sizable demolition charg¬es, charges that are large enough to do a lot more than emit the “puffs of smoke” cited as evidence for the explosives hypothesis. I’ve seen both live and filmed explosive building demolitions. Each explosion is accompanied by a very visible shower of heavy rubble and a dense cloud of smoke and dust. Just that fact alone makes the explosives hypothesis untenable; no demolitions expert in the world would be willing to promise his client that he could bring down a tall building with explosions guaranteed to be indistinguishable from the effects of an aircraft impact.”
2. Elastic waves launched from the collapse front quickly filled the building – both lower structure and upper block – with large dynamic stresses, which weak¬ened and ruptured joints well in advance of that material entering the collapse front.
In a forthcoming instalment of this report, I will address the topic of heat, a prominent feature of many conspiracy theories about the collapse of the WTC buildings. CP
Manuel Garcia a native New Yorker who works as a physicist at the Lawrence Livermore Laboratory in California with a PhD Aerospace & Mechanical Engineer¬ing, from Princeton. His technical interests are in fluid flow and energy, specifically in gas dynamics and plasma physics; and his working experience includes measure¬ments on nuclear bomb tests, devising mathematical models of energetic physical effects, and trying to enlarge a union of weapons scientists.
paul 4:53 AM
It is inconceivable that our demolitions
expert would time his surreptitious explosions to occur HOURS after the aircraft impact. He couldn’t possibly be absolutely certain that the impact fires would even last an hour. Quite the opposite:
to mask the booster explosions, he’d time them to follow right on the heels of the impact.
But not apparently to spontaneously fall at the speed of gravity a few hours later. Rereading it, its still recognisably chuck jones physics
The other story in this issue is about an encounter with an fbi iraqi provocateur:
If there really are so many horrible,
dangerous terrorists out to get us, why, then, is the FBI wasting time and resources trying to provoke me into making some unlawful statement? Why are our intelligence agencies infiltrating meetings of peace groups, like the one in Lake Worth, Florida, that NBC News discovered was attended by the DOD? I attended that meeting and was one of its organizers and presenters. The subject was counter-recruitment. Is that a national
security threat? Am I?
She sounds like a paranoid ceeteeist to me. Maybe cockburn's editorial policy is suffering under the strain of defending us from the loons.
Listen to this to hear from a disgruntled cp star contributor
warszawa 11:32 AM
Auld Occam's not in with a shout.
Few know what he's really about.
"If simple, then right"
Is the vulgarised shite
That's touted by many a lout.
warszawa 11:52 AM
It's truly awful stuff. Like Hitchens, Cockburn has clearly lost it.
"Mass psychosis is a myth held in common, which releases the population from the “normal” restraints of rationality and international social conventions, so they can pursue their mythical vision. The ignorance — and the fears that spring from it as prejudices — of the entranced population is “projected” onto “enemies” whose destruction is sought in the irrational effort to eliminate the actual problem of psychological tensions."
Did someone mention the War on Terror? Cockburn didn't, funnily enough; or at least not intentionally. Remarkable thing, the subconscious mind.
"The myths we construct to express our understanding of the realities we are immersed in are limited by the range of our knowledge."
Unless we are Alexander Cockburn, of course, blessed with omniscience and heroically independent of comforting myths.
"The events of September 11, 2001, were unsettling for many Americans because their existing myths were shattered;
these myths had provided comfort and lain undisturbed in consciousness since indoctrination had lodged them there."
By contrast, the comforting 'Imperial Blowback' myth embraced by Cockburn and most left clerks cannot be shattered by any evidence whatsoever. Perhaps that's why he defends it with such panicky vehemence. Perhaps that's why he sounds like a Christain fundamentalist trying to explain the existence of dinosaur bones.
His rubbish about Occam really deserves a full post to itself.
- Thanks for posting this, Paul.
paul 12:09 PM
So, trust in government has been broken, fear of its power is vivid, and understanding of the physical mechanisms of Nature is limited. This psychology will naturally sprout conspiracy theories about 9/11.
As well as not being much of a physicist, i'm not much of a logician but that looks like a clear case of an undistributed middle to me.
lack of trust in govt, vivid fear of its power, all sounf quite sensible to me, not a pathological, psychological condition.
warszawa 12:46 PM
"lack of trust in govt, vivid fear of its power, all sound quite sensible to me, not a pathological, psychological condition. "
Yes, it's really shocking stuff from Cockburn; naked power-worship.
I wonder what he thinks trust in government and dull love of its power will 'spawn'? He should put down those physics primers, which are clearly hurting his brain, and pick up an introduction to 20th-century history. Or he should just take a glance at the bloody newspaper. (I wonder if Cockburn has noticed the abolition of habeas corpus, the legalisation of torture and the granting of retroactive immunity to the President against prosecution for war crimes?)
paul 11:37 PM
The terrible thing about blowback is that it suggests some universal force of balance (reaping what you sow, markets equilibrating, justice will out, work hard and you'll get your reward, the real bosses will step in and stop bushco etc) which is a comfort, I suppose, though everything looks precariously out of balance to me.
I should have added 'capitalism has its own gravediggers' to that sorry list of self correcting mechanisms
Qlipoth: Shutting down a hate group
Posted by Qlipoth at 9:41 AM
livingfossil 5:24 PM
"No conservative would ever..."
Yea, they would just like organize an armed militia group and drive back and forth looking for like, running brown people to like, sequester, and maybe like rough up, and stuff. Chanting is for libruls.
brownfemipower 7:42 PM
exactly. that part almost ruins the rest of the tape for me....
Off topic but cockburn's mad as hell and he's not going to take it anymore
Practically a whole issue dedicated to debunking, now I'm no physicist, but you could ask for a real world example of this perfectly reasonable sequence of events and you could ask what happened to wtc7 and you could be forgiven for asking if this guy is a mass pschologist as well.
Billy occam gets exhumed as usual.
Counterpunch vol 13 no 16
Five years after the events of September 11, 2001, conspiracy theories abound as an anxious public seeks to find a comprehensible story for that day and more broadly for their so¬cio-political world. People need reliable foundations upon which to base the many assumptions and conventions they use to carry on their lives.
Half a century ago, public anxiety about the danger of atomic energy and the terror of thermonuclear war exhibited itself in sightings of flying saucers, and a fad of monster movies. C. G. Jung wrote about flying saucer sightings as an instance of “mass psychosis”: a “psychological infection” that spreads among people who lack sufficient understanding to rationalize fearsome political forces and unstable so¬cial conditions (Flying Saucers: A Modern Myth, 1958). Jung was sensitive to any indication that another “psychological epi¬demic” might erupt, as Nazism did, among a population whose government possessed awesome military power. Mass psychosis is a myth held in common, which releases the population from the “normal” restraints of rationality and international social con¬ventions, so they can pursue their mythical vision. The ignorance — and the fears that spring from it as prejudices — of the entranced population is “projected” onto “enemies” whose destruction is sought in the irrational effort to eliminate the actual problem of psychological tensions, (1)
A more entertaining expression of popular anxiety is the monster movie. “Godzilla,” “Rodan,” “Them,” “The Thing” and many others safely frightened viewers with stories of monsters whose
introductions into human society were caused by atomic bomb testing, or were accompanied by radioactivity. For most Americansthe major source of any knowl¬edge of physics is probably this type of motion picture.
The myths we construct to express our understanding of the realities we are im¬mersed in are limited by the range of our knowledge. When the myths are meant to cover over fears about forces beyond our control, they can be conspiracy theories. Consider these pairings of fears and ra¬tionalizations:
* fear of political power/conspiracy theories;
* metaphysical fear (fear of death)/re¬ligion, a theological conspiracy ;
*fear of personal inadequacy/racism,
*fear of strange cultures/ultra-nation¬alism
Certainly, so long as there are more than two people on Earth, conspiracies will occur. But too often we invoke a conspiracy in constructing our story of the world because we lack specific information about the sciences, economics, history and other relevant fields of specialized knowl¬edge. Experience has shown that if the evidence allows for several explanations to a given problem then the hypothesis with the fewest assumptions is most probably correct. This principle is called Occam’s Razor and is attributed to the 14th-century English logician and Franciscan friar Wil¬liam of Ockham (c. 1295–1349) (2).
The events of September 11, 2001, were unsettling for many Americans be¬cause their existing myths were shattered;
these myths had provided comfort and lain undisturbed in consciousness since indoctrination had lodged them there. The increasing power of communications tech¬nology – global telephone networks, the Internet – and the accelerating disregard of subtlety by the elite in its management of public perceptions about government policies has eroded the myths – or illu¬sions – of many Americans. So, trust in government has been broken, fear of its power is vivid, and understanding of the physical mechanisms of Nature is limited. This psychology will naturally sprout conspiracy theories about 9/11.
The reports on the investigations of the collapse of the World Trade Center build¬ings conducted by the National Institute of Standards and Technology (originally the National Bureau of Standards) are to be found at a special NIST website (“NIST & The World Trade Center, Final Report (Sept. 2005),” http://wtc.nist.gov/pubs/#draft (September 11, 2006).
This multi-volume Final Report, issued in September 2005, is the “official word.” There is a vast amount of dry text, much data, descriptive summaries of detailed calculations of the impact ruptures, fires and heating, subsequent deformation, load-shifting, buckling and ultimate fail¬ure of the buildings. NIST addressed the sequence of events and shifting of loads leading up to the failure that allowed the upper blocks to drop; it did not proceed to a detailed simulation of the collapses to the ground. NIST justified this on the grounds that there was sufficient energy in the descending blocks to crush the lower structures, once failures had occurred.
The controlled demolition hypoth¬esis for the collapse of the World Trade Center buildings is described at length in a Wikipedia article (“Controlled demolition hypothesis for the collapse of the World Trade Center”)
The popularity of 9/11 conspiracy theories (also outlined in a useful Wikipe¬dia entry) has prompted NIST to present a very nice webpage addressing the usual questions of the conspiracy viewpoint, and providing clear descriptions in non-techni¬cal English of the physics and engineering explanations embodied in the NIST WTC Towers Final Report .
The World Trade Center Towers (WTC 1, WTC 2) were tall square buildings with supporting columns grouped along the vertical axis (center) and closely spaced along the perimeter (building faces). A “hat truss,” at the top of each building, tied the outer walls to the central columns; and this truss had a height equal to that of five stories.
A hijacked airliner was crashed into each building about 10 or 20 stories down from the top. The columns along one face of the building were sheared for a height of several floors, as were many of the columns at the core. The exploding fuel from the airliner ignited fires throughout the levels within the impact zone, as well as dropping fire down the stairwells and elevator shafts at the building’s core, and billowing up to higher levels. The shocks of impact and detonation loosened the “fire protection” thermal insulation on steel beams in the impact zone.
The damaged core columns in the im¬pact zone could no longer hold up all the weight they were meant to carry. The core columns in the upper block now found it necessary to partially hang from the hat truss. The hat truss pressed down much more forcefully on the perimeter columns, transferring the load of the hanging weight. The added compression of the perimeter columns could only be distributed to the three undamaged faces, and because of the irregularity of the damage one face assumed a much higher load than the other two.
The fuel fire burned up to 1,100 degrees C (2,000 degrees F) for perhaps 10 min¬utes. It ignited the many plastic furnishing (carpets, curtains, furniture, equipment cases, clothing, fixtures, office ceilings and partitions), paper items (paper supplies, books, pressed wood), and some structural elements (gypsum wall boards, plastic plumbing), which then continued the fire. The exposed steel beams in the impact zone heated to between 700 C to 1,000 C. Steel at 700 C has 50 per cent to 70 per cent of its strength at habitable temperatures; and steel at 1,000 C has between 10 per cent to 30 per cent.
The floors in the impact zone sagged because of broken joints to central col¬umns, heat causing their metal framing to soften, weaken and expand; also because of the weight of debris fallen from above . The sagging floors twisted their joints to the perimeter columns (on the three intact faces); the length of column above a floor joint being twisted inward. For one face of the building, the combined stress of the original weight above it, the added com¬pression from the hat truss, and the torque from the sagging floors were too much. Its perimeter beams were bent inward to the point of failure, and they buckled.
The NIST investigation was an ex¬tremely detailed analysis by 200 engineers and building professionals, describing the conditions of the buildings from the instant an airplane collided to the moment a collapse began. The next section of this CounterPunch report carries the story downward from the point where NIST leaves off. NIST concentrated its resources on the greatest uncertainty: what initiated the collapse? It was understood that once an upper block of the building was in mo¬tion the structure below would be unable to counter the dynamic forces, and collapse would proceed to the ground.
Physics Problem Number 1: Free Fall of the WTC Towers
“How could the WTC towers collapse in only 11 seconds (WTC 1) and 9 seconds (WTC 2), speeds that approximate that of a ball dropped from a similar height in vacuum (with no air resistance)?” (NIST FAQ #6)
The suspicion behind this question is that the Towers were weakened by sur¬reptitious, controlled demolitions. In this view, the structure below the impact zone (where airplanes collided, exploded, and fires burned) “should have” provided re¬sistance to the descent of the block above the impact zone, slowing or even stopping the collapse.
The NIST response is that the lower structure was only designed to hold up the weight above any given floor statically, not dynamically. The force imparted by the collision of the upper block was beyond the limits of the lower structure to resist. The lower structure was essentially crumbled by a “hammer” of descending material, and the mass of this hammer increased during the course of the collapse.
Problem 1, Force Balance
Once the framing in the impact zone has failed, the upper block is accelerated by gravity until it crashes into the lower structure below the impact zone. Labeling the mass of the upper block m, and its speed v, the block would have a momen¬tum m*v and an energy of (1/2)*m*v^2. Its weight would be m*g, where g is the constant of gravitational acceleration (9.81 meters/second^2).
The balance of forces on the upper block as it impacts the lower structure is presented here as the impulse momentum form of Newton’s 2nd Law:
Here, positive direction, velocity and force are taken to
 be vertically upward; dt is a label for “delta t”, a very brief time in¬terval during which the impact occurs and the momentum changes from m*v(initial) to m*v(final); and F is the force of resist¬ance by the lower structure. If A is the net horizontal cross-sectional area of the load-bearing columns of the lower structure, then F/A is the average compressive stress across that area.
When an upper block drops through an impact zone that has lost structural strength, and crashes into the rigid lower structure, it imparts a dynamic force in ad¬dition to its weight. The dynamic force is the second term in the last expression for F. The total force, F, acts during the time interval dt during which the momentum of the upper block is reduced (in magnitude) from m*v(initial) to m*v(final). Clearly, the lower structure will crumble when F is greater than the maximum force it can support, or when F/A is greater than the maximum stress it can withstand.
Problem 1, Numerical Example of Progressive Collapse
v(t) = -g*t, (negative sign for down¬ward direction),
What actually happened in the build¬ings? We consider a suggestive numerical example.
We will assume these floor structures to be dL = 1 meter thick (1 meter = 3.28 feet). Each floor structure is a framework of steel below and within a layer of con¬crete. The floors spanned a distance of between 10 m and 20 m between the outer square perimeter (63.4 m a side) and the core support along the axis of the building, which housed elevator shafts, stairwells and support columns, within a rectangular area of [42 m x 27 m].
The waves alert the volume of the floor structure to the imposition of a new load, and infuse that volume with much higher stress. The floor structure is deflected downward a distance d = -0.077 meters (3 inches) during impact. In becoming stressed, the floor structure absorbs some of the energy of the descending block, slow¬ing it by dv = 0.5 m/s (in this example). Within dt = 1/100 s, the floor structure has transmitted the force of the new load to its joints with the building’s core and periphery.
Problem 1, Wave Trains and Stress Concentration
Elastic waves are launched from the collapse front (the leading edge of de¬scending material, like “weather front”) at the moment of first impact. Within 0.01 s, a stress wave has traveled through the metal framework to five levels below the collapse front, a distance of 20 m. These gation showed conclusively that the failure of the inwardly bowed perimeter columns initiated collapse and that the occurrence of this inward bowing required the sagging floors to remain connected to the columns to pull the columns inwards. Thus, the floors did not fail progressively to cause a pancaking phenomenon.”
For a shot from the hip two days after the collapse, Bazant did pretty well. But, after the NIST legion did all the neces¬sary homework, we now have an accurate result. NIST shows pictures of the inward buckle of the perimeter wall, taken from a police helicopter. Pancaking versus NIST is a nonexistent technical argument only to be found in the imagination of some conspiracy-minded people. The technical community migrated from early hypoth¬eses of the initiation, like pancaking, to the NIST conclusions as a consequence of doing the hard work required. And, there was always unanimity on what drove the collapse once it was initiated: excess dynamic force produced from the gravi¬tational potential energy contained within even one level spacing. Once the top began to fall, it was going to crush the building below it, regardless.
The Absurdity of “Controlled Demo¬lition” (Red Herring #2)
Pierre Sprey is CounterPunch’s techni¬cal reviewer of this report. His comments about the controlled demolition hypothesis are so cogent that I include them here.
“There is not the slightest need to postulate pre-placed explosive charges to explain why the towers collapsed at near free fall speeds. Let me note a few practical aspects of explosive demolitions that make the explosive charge hypothesis improb¬able to the point of absurdity:
“1. Any demolitions expert concocting a plan to hit a tall building with an airplane and then use pre-placed explosives to UN¬DETECTABLY ensure the collapse of the building would never place the explosives 20, 30 and 60 floors below the impact point. Obviously, he would put the explosives on one or more floors as close as possible to the planned impact level.
“2. It is inconceivable that our demoli¬tions expert would time his surreptitious explosions to occur HOURS after the aircraft impact. He couldn’t possibly be absolutely certain that the impact fires would even last an hour. Quite the oppo¬site: to mask the booster explosions, he’d time them to follow right on the heels of the impact.
“3. To ensure collapse of a major build¬ing requires very sizable demolition charg¬es, charges that are large enough to do a lot more than emit the “puffs of smoke” cited as evidence for the explosives hypothesis. I’ve seen both live and filmed explosive building demolitions. Each explosion is accompanied by a very visible shower of heavy rubble and a dense cloud of smoke and dust. Just that fact alone makes the explosives hypothesis untenable; no demolitions expert in the world would be willing to promise his client that he could bring down a tall building with explosions guaranteed to be indistinguishable from the effects of an aircraft impact.”
2. Elastic waves launched from the collapse front quickly filled the building – both lower structure and upper block – with large dynamic stresses, which weak¬ened and ruptured joints well in advance of that material entering the collapse front.
In a forthcoming instalment of this report, I will address the topic of heat, a prominent feature of many conspiracy theories about the collapse of the WTC buildings. CP
Manuel Garcia a native New Yorker who works as a physicist at the Lawrence Livermore Laboratory in California with a PhD Aerospace & Mechanical Engineer¬ing, from Princeton. His technical interests are in fluid flow and energy, specifically in gas dynamics and plasma physics; and his working experience includes measure¬ments on nuclear bomb tests, devising mathematical models of energetic physical effects, and trying to enlarge a union of weapons scientists.
paul 4:53 AM
It is inconceivable that our demolitions
expert would time his surreptitious explosions to occur HOURS after the aircraft impact. He couldn’t possibly be absolutely certain that the impact fires would even last an hour. Quite the opposite:
to mask the booster explosions, he’d time them to follow right on the heels of the impact.
But not apparently to spontaneously fall at the speed of gravity a few hours later. Rereading it, its still recognisably chuck jones physics
The other story in this issue is about an encounter with an fbi iraqi provocateur:
If there really are so many horrible,
dangerous terrorists out to get us, why, then, is the FBI wasting time and resources trying to provoke me into making some unlawful statement? Why are our intelligence agencies infiltrating meetings of peace groups, like the one in Lake Worth, Florida, that NBC News discovered was attended by the DOD? I attended that meeting and was one of its organizers and presenters. The subject was counter-recruitment. Is that a national
security threat? Am I?
She sounds like a paranoid ceeteeist to me. Maybe cockburn's editorial policy is suffering under the strain of defending us from the loons.
Listen to this to hear from a disgruntled cp star contributor
warszawa 11:32 AM
Auld Occam's not in with a shout.
Few know what he's really about.
"If simple, then right"
Is the vulgarised shite
That's touted by many a lout.
warszawa 11:52 AM
It's truly awful stuff. Like Hitchens, Cockburn has clearly lost it.
"Mass psychosis is a myth held in common, which releases the population from the “normal” restraints of rationality and international social conventions, so they can pursue their mythical vision. The ignorance — and the fears that spring from it as prejudices — of the entranced population is “projected” onto “enemies” whose destruction is sought in the irrational effort to eliminate the actual problem of psychological tensions."
Did someone mention the War on Terror? Cockburn didn't, funnily enough; or at least not intentionally. Remarkable thing, the subconscious mind.
"The myths we construct to express our understanding of the realities we are immersed in are limited by the range of our knowledge."
Unless we are Alexander Cockburn, of course, blessed with omniscience and heroically independent of comforting myths.
"The events of September 11, 2001, were unsettling for many Americans because their existing myths were shattered;
these myths had provided comfort and lain undisturbed in consciousness since indoctrination had lodged them there."
By contrast, the comforting 'Imperial Blowback' myth embraced by Cockburn and most left clerks cannot be shattered by any evidence whatsoever. Perhaps that's why he defends it with such panicky vehemence. Perhaps that's why he sounds like a Christain fundamentalist trying to explain the existence of dinosaur bones.
His rubbish about Occam really deserves a full post to itself.
- Thanks for posting this, Paul.
paul 12:09 PM
So, trust in government has been broken, fear of its power is vivid, and understanding of the physical mechanisms of Nature is limited. This psychology will naturally sprout conspiracy theories about 9/11.
As well as not being much of a physicist, i'm not much of a logician but that looks like a clear case of an undistributed middle to me.
lack of trust in govt, vivid fear of its power, all sounf quite sensible to me, not a pathological, psychological condition.
warszawa 12:46 PM
"lack of trust in govt, vivid fear of its power, all sound quite sensible to me, not a pathological, psychological condition. "
Yes, it's really shocking stuff from Cockburn; naked power-worship.
I wonder what he thinks trust in government and dull love of its power will 'spawn'? He should put down those physics primers, which are clearly hurting his brain, and pick up an introduction to 20th-century history. Or he should just take a glance at the bloody newspaper. (I wonder if Cockburn has noticed the abolition of habeas corpus, the legalisation of torture and the granting of retroactive immunity to the President against prosecution for war crimes?)
paul 11:37 PM
The terrible thing about blowback is that it suggests some universal force of balance (reaping what you sow, markets equilibrating, justice will out, work hard and you'll get your reward, the real bosses will step in and stop bushco etc) which is a comfort, I suppose, though everything looks precariously out of balance to me.
I should have added 'capitalism has its own gravediggers' to that sorry list of self correcting mechanisms