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Monday, February 11, 2013 - 8:05pmSanction this postReply
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Watch this video of the south tower collapsing. Then come back here and tell me that having a fire on a few upper floors causes the entire building to launch streams of crumbled material out the sides. That the large steel framed upper chunk of building would begin to rotate to the side (normal), and then disintegrate mid air without explosives (yea right). That the upper disintegrating material would crash through a completely intact steel framed building just as fast as the crumbled material launched to the sides... (yea right)

Because yea, that's always what happens to buildings that are on fire... especially steel framed ones.

Some architects & engineers thoughts on 911

Meanwhile replying to this video, eat your milk and Cheerios (just like the FDA food pyramid says), that you paid for using your fiat dollars which were once backed by gold that was stolen from american bank deposits. And also include the phrase "He's got 'em" to make your post more credible. "Saddam Hussein is a man who told the world he wouldn't have weapons of mass destruction, but he's got them." - Bush Nov 3, 2002

Post 1

Monday, February 11, 2013 - 10:28pmSanction this postReply
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I'm not going to argue with Dean. I've found that people get a certain depth into conspiracy theories and they are no longer willing to consider anything else. But for the rest of you, I'll say that there are very clear explanations given by other architects and engineers that shred the stuff Dean presented.

Does anyone really think that Bush or some rogue agency or group set the towers up to blow with explosives and then got some people to hijack planes and to fly them into the towers and that this whole conspiracy worked and that no one has talked? Yeah, that kind of thing really happens all the time.

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Tuesday, February 12, 2013 - 5:39amSanction this postReply
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Steve, Your argument is the same as a religious fanatic who says the bible must be true because there's no way the people who wrote it could get away with lying about the Jesus story. Next you will want me to believe Jesus existed died, was buried, and then came back to life 3 days later, since its inconceivable that people lied. Then you will want me to believe that Moses parted the sea, since its inconceivable that people lied.

Watch the video of the south tower collapsing. Think for yourself about how steel structures work. Do steel structures allow objects of equal or lesser size & weight to fall through them at the speed of freefall?

It would make more sense to argue about who planted the explosives than to deny that explosives were not involved.
(Edited by Dean Michael Gores on 2/12, 6:06am)


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Tuesday, February 12, 2013 - 6:14amSanction this postReply
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Is it possible that explosives were onboard the plane?

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Tuesday, February 12, 2013 - 8:01amSanction this postReply
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Jules: You tell me. What do you think an explosion centered at the plane crash site would look like?

Here's the lesser known building 7's collapse. This one was destroyed in a more common fashion: the bottom center is blown up first, it caves in, and then each floor is exploded as it reaches near the ground. Ever seen a steel building go down like that due to a fire?

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Post 5

Tuesday, February 12, 2013 - 8:09amSanction this postReply
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I haven't done any research on this recently. I am not prone to believing conspiracy theories and I am generally satisfied with the explanation Steve gave. We live in a different age than when Jesus was around (assuming he was around). I can't believe that the government could effectively pull off something this grand, and no one would eventually find out about it. Our government can't do anything else that effectively, so why would you believe it in this case?

That being said, I remember about 5 years ago listening to a materials science engineering professor talk about the towers. He said that the material that the buildings were made of can get very brittle at high temperatures, which can of course lead to collapsing. It is a mistake to think of this material as having the same properties as at room temperature, it's totally different. This was a known weakness of the buildings, but it wasn't exactly practical to build them out of Tungsten, it would cost a fortune.

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Tuesday, February 12, 2013 - 8:27amSanction this postReply
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Dan: Note that I'm not arguing that the top portion of the building couldn't fall over due to a plane crash. I'm arguing that the top of the building couldn't fall through the rest of the intact building at free fall.

Might I also point out that higher quality videos are now available than back in 2001. You can see in detail things that once were invisible. In 2001 it looked like a cloud falling. Now you can see more detailed videos of the sequential explosions.
(Edited by Dean Michael Gores on 2/12, 8:55am)


Post 7

Tuesday, February 12, 2013 - 1:11pmSanction this postReply
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Dean,

People believe the bible, then and now, not because of eyewitness credibility or a rational examination of the related events, but on pure faith. So, your little anology doesn't hold up. You wrote:
Next you will want me to believe Jesus existed died, was buried, and then came back to life 3 days later, since its inconceivable that people lied.
Nope - I reject the return-to-life hypothesis for the same reason I reject the claims of the 911 truthers - the evidence doesn't stand rational examination. And I also do not believe we should accept a conspiracy just because people sometimes lie - as if conspiracy paranoia were some sort of lie detector.
------------------

Everyone Else,

Again, not for Dean who appears to have settled into the self-satisfied psychological position that conspiracy people get into, but for everyone else, here are some links for arguments against the 911 Truther's claims:
  • This article has an excellent intro in the Who's Who of the Truther movement and does a good job of blowing up the psuedo-scientific claims.
  • Here is a comprehensive set of links on the issue on a site belonging to Mark Roberts, one of the key anti-Truther proponents.
  • Here is the Wikipedia link to the 911 conspiracy theories.
  • This web page is an on-line journal of papers (mostly linked pdf files) from different authors that debunk the different aspects of the Truther nonsense.

(Edited by Steve Wolfer on 2/12, 2:55pm)


Post 8

Tuesday, February 12, 2013 - 2:13pmSanction this postReply
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Steve, I will look at your links. Can you look at the video compilation of the south tower collapse and think for yourself about what it should look like?

Post 9

Tuesday, February 12, 2013 - 3:04pmSanction this postReply
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Dean,

I looked at the video and then I read the explanations for that building's collapse from various source, including the National Institute of Standards (Here). I don't find the Truther's assertions to be convincing.

The problem with conspiracy theories is in the motivation - the focus is on the theory's deepest implications ("the Bush admin did this" or "the Bush admin knew this was going to happen, and let it happen" or something like that) and if one alleged fact put forth in support of the theory is debunked (like bldg 7's collapse, then another convenient 'fact' is found. It becomes, "You can't convince me, no matter what how many of my assertions you prove to be inadequate - I'll just find more!" We've both argued with religious people that do that.

Post 10

Tuesday, February 12, 2013 - 6:22pmSanction this postReply
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In one of our favorite shows, NUMB3RS, they riff on the Kennedy Assassination.  One of the mainstream believers says that there is no way that you could keep the conspiracy quiet with hundreds of people talking from the FBI and CIA and so on.  And the conspiracist replies, "... which is why everyone is talking about it..."

Just sayin'... I personally think that 9/11 was what it appeared to be. But I am open minded.  I was a Pearl Harbor Denier until I found out that Franklin D. Roosevelt served seven years as the Assistant Secretary of the Navy in the Woodrow Wilson Cabinet.  ... no way he didn't know...  So, I maintain a margin of suspended disbelief.

On my blog are two comments about James Gleick's book about Richard P. Feynman.  In Cargo Cult Science, Feynman warned not to fool yourself.  That cuts both ways. Feynman was comfortable with not knowing.  I am, too. Ambiguity is acceptable to me.  I seldom meet an Objectivist who is. So, we have this argument right here and now. As I said, I think that 9/11 played out as described.  But I am not arguing.


Post 11

Tuesday, February 12, 2013 - 7:27pmSanction this postReply
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[deleted double-post]

(Edited by Ed Thompson on 2/12, 7:34pm)


Post 12

Tuesday, February 12, 2013 - 7:34pmSanction this postReply
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I'm okay with not knowing some things (Are you surprised, Mike?).

:-)

Part of the reason for that is simple necessity: Singularity or no singularity, there is no way that you can come to know all things. Sometimes, the things you want to know are protected by privileged access, such as the combination to a bank vault. In those cases, informed parties are incentivized to keep the truth from you. An alternative is to destroy all informed parties that have anything but the very most skin in the game, as when a criminal mastermind kills his own accomplices -- because that guarantees that the trail will never be brought back to him.

Another way to come at the issue is to pass moral judgment: Are politicians people of exceptional character? Is the current system set up to attract the absolute worst among us (as many famous historical quotes convey)? Let's pretend that's true. Let's pretend that the system is set up to attract the absolute worst among us. I'm talking about people who don't create any value, but that only get ahead in life by tarnishing others -- by illegitimately stepping on their shoulders or by trampling over their corpses (depending on degree of ruthlessness). See if you can recall any recent politicians that might fit that bill. Now ask yourself: What wouldn't they do? What act would they say is just too much?

It's doubtless that many secrets have been carried to the grave. There is a higher-than-normal death rate for individuals working alongside politicians. There are plays written about such things. There are history books with many examples. The difference between WMDs and an inciting YouTube video is merely of degree -- it is not a difference in kind. We may never know the details of many things, but we can still piece together a picture of someone's character from those fragments that we do find out about and then work to properly integrate. It may save our lives someday.

I'm still withholding judgment about the towers. Over 2900 people were killed, which attracts a lot of attention. I think it was G. Khan who killed over a million people living in territory that he controlled, but he lived in a different time. Honest brutality was tolerated back then. People have morally improved, however -- though leaders may be just as evil as they ever were -- so it is no longer possible to be both brutal and honest about it.

Ed


Post 13

Tuesday, February 12, 2013 - 9:00pmSanction this postReply
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This is a compression stress test of a concrete cylinder, the kind of test performed 1000's of times every day by material testing labs across the country. The pressure is applied gradually and ends when the material fails. There is a reason it's done in a cage: to prevent material from flying out and injuring someone. Imagine forces much, much larger applied suddenly...

http://www.youtube.com/watch?v=lWVeYTOJBzA

Post 14

Wednesday, February 13, 2013 - 1:33amSanction this postReply
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Steve,

I've looked through some of the stuff you've linked to.  Sorry, but when the authors start attacking straws instead of explaining physical evidence (such as free fall, symmetric collapse, and no prior history of a steel building collapsing due to fire) I quickly loose interest.

May 2011 BBC Interview with Dr. Niels Harrit... I really like how the guy keeps on suggesting that we look at hard evidence and use science.  Gotta love (sarcasm) how the interviewer repeatedly attacks straws and attempts to get the interviewee to say something that is politically sensitive.  Its amazing that Dr. Niels Harrit kept his cool during the interview.  I'd tell the guy that I would leave the next time he repeated the "What do you suppose the motivation would be?" question...  because first you have to believe the evidence before you can start to question who you can trust.  Doing the opposite (trusting people first instead of looking at evidence for yourself) leads to stampedes of cattle running over cliffs.

There is more evidence supporting more went on than airplanes crashing into the building.  Liquid iron/steel was dripping out of the south tower right before it collapsed.  For 3 months (if I remember the professor saying correctly, which the interviewer didn't debate) molten metal was stewing at the bottom of the collapse sites, which hampered the cleanup process.  Microscopic spheres of iron (which can only be caused by exploding molten iron) were found in the dust which the scientist claims to have very good record of coming from the towers.  Also, thermitic material (which is used to melt iron/steel) was found in some dust.

He claims no physical evidence has been shown that shows the 19 terrorists boarding the planes.  I haven't seen any security footage of this myself...  enough for now, time for bed.


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Post 15

Wednesday, February 13, 2013 - 5:38amSanction this postReply
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Dean:

First of all, once the top floors started to collapse, a pressure wave was transmitted through the entire building that moved at the speed of sound (approx 1100 ft/sec.)

That is what the speed of sound is; the speed at which pressure disturbances are transmitted through air.

"Free fall" is much, much slower than the speed of sound.

Second of all, it was a semi rigid steel tube with poured concrete floors stacked inside the shell; the dynamic loads from the floors collapsing above travel through that steel shell at speeds much faster than the speed of sound in air.

You are not seeing the results of chemical explosions. You are seeing potential energy being converted to kinetic energy by way of pressure disturbances moving through that building at the speed of sound.

As well, there appears to be a video cut in that video; missing frames to accentuate the abruptness of the event.

You've been internet hoaxed. Sorry, it happens.

What is the name of this website again?

PS: whoever uploaded the video noted "some cropping and stabilization." Not in every clip, but some of those clips only include every other or even every third frame. You can tell which because of the continuity.

Imagine even just one floor collapsing; one second, there is a 10 ft space of air. When the floor above collapses, at some point, that 10 ft of air is now compressed to 1 inch. What compression ratio is that? Where does that air go? At what speed does that overpressure propagate inside the building to the floors below?

What you are seeing is the internal overpressure in the building exceeding the ability of the windows to stay intact in the floors below; that overpressure is experienced over the entire window and resisted only by the frame. It doesn't take much overpressure to create a huge force.

What 'precedes' the falling of the floors above looks entirely consistent with overpressure wave propagating ahead of the giant 'piston' falling from above. The pressure wave from that piston travels through the building at the speed of sound, not the speed of 'free fall.'

regards,
Fred


(Edited by Fred Bartlett on 2/13, 5:59am)


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Post 16

Wednesday, February 13, 2013 - 6:43amSanction this postReply
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Imagine for a second that you are on the ground floor of the WTC. You have mounted electronic strain gages on the columns in the wall. You are recording the strain on those columns dynamically, and recording on your laptop.

At the same time, you have dynamic pressure transducers mounted in that same room at the ground floor.

You are watching a real time video of the event on a TV.

You are real time monitoring the output of the pressure transducers, and strain gages on your laptop. Superimposed on the video of the collapse, you have the dynamic output of your pressure transducers and strain gages on the ground floor, frame by frame.

A hundred floors above you, the floors start pancaking, one on top of the other. Bang-bang-bang.. at "free fall" speed.

What do you record on the pressure transducers? What do you record on the strain gages?

At what speed are the pressure disturbances reaching you?

At what speed are the dynamic loads in the steel building reaching you?

Must you wait for 'free fall' to realize the physical impact of what is going on above your head or will that dynamic event propagate at the speed of sound through the air, and at a much faster speed through the steel frame of the building?

Does nothing at all happen until the ceiling above you literally falls on your head, or are there dynamic loads pounding those columns and a pressure wave building up inside the building ahead of the collapse?

Where does the 'free fall' speed limit come from, the one that trumps the speed of sound in air or the bulk modulus of steel?

It comes from ignorance; it comes from the least common denominator that is the in-ter-net.

We all get to weigh in on shit we don't understand based on common sense and our daily experience.

Our trust in inscrutable calculus of others is completely broken, ever since JFK was assassinated in front of our very eyes. Because far too often, that mistrust is totally justified.

We need to check each other's math, and sometimes that is just too damn hard to do, leaving the nation in a constant state of paranoia.

Jules, it's just like that movie, "Cube."

regards,
Fred





Post 17

Wednesday, February 13, 2013 - 8:00amSanction this postReply
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Dean said that if I'd look at his video link, he'd look at the links I sent. He certainly didn't look very much, because explanations, like Fred's excellent explanation above, were in several of those links I supplied. It's like I said, when someone gets too deep into a conspiracy theory, the theory takes over and if someone shoots down one piece of false evidence the 'truther' comes up with another. Discussions with them become like whack-a-mole but not as much fun.
------------------

Fred wrote:
Imagine even just one floor collapsing; one second, there is a 10 ft space of air. When the floor above collapses, at some point, that 10 ft of air is now compressed to 1 inch. What compression ratio is that? Where does that air go? At what speed does that overpressure propagate inside the building to the floors below?

What you are seeing is the internal overpressure in the building exceeding the ability of the windows to stay intact in the floors below; that overpressure is experienced over the entire window and resisted only by the frame. It doesn't take much overpressure to create a huge force.

What 'precedes' the falling of the floors above looks entirely consistent with overpressure wave propagating ahead of the giant 'piston' falling from above. The pressure wave from that piston travels through the building at the speed of sound, not the speed of 'free fall.'
As a non-engineer, I'd add this... When a floor collapses, the weight of that floor, and the weight of all of the floors above it, land on the floor just below. This is a conversion of what had been a static load, an amount the support columns were designed to handle, into a dynamic load. Those support columns, instead of holding x number of tons which are not in motion, are now trying to hold up against the shock of x number of tons multiplied by y feet per second of motion. Velocity is the great multiplier of force. (Imagine holding a 40 caliber bullet in the palm of your hand, versus getting shot in the hand with that bullet.)

And, if there is any longitudinal elastiscity in the support columns, that is, any ability to compress some small amount without loss in support integrity, that capacity will be spread out over the columns below during the passage of a small unit of time. As each floor below starts to compress, there is a touch less force to be converted to those still further down. When there are 100 floors below, that's a lot of floors to spread out the force of the 102nd floor driving into the 101st floor. But each time this happens there are fewer flights below, and that capacity to accept some degree of compression is disappearing - so the force generated by each floor collapsing is going to increase - because of the greater weight now in motion, but also in the loss of ability to absorb that lies below. Each floor that is currently receiving the collapse is subjected to the full force of the weight above times the speed of collapse. Thus, with each floor's collapse, there is more weight added to that which is in motion and fewer floors below to absorb a fraction of the force with non-destructive compression. Faster collapses as this happens will increase the forces Fred described (the same amount of air being compressed the same amount - but in slightly less time). The other thing I remember from one of my classes, eons ago, is the gas law. To decease the volume of air that much in that short a time is not only going to generate massive pressure, but also a huge increase in temperature. I wonder if anyone has computed the pressure related temperatures?

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Post 18

Wednesday, February 13, 2013 - 11:46amSanction this postReply
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Fred, you make straw arguments and refer to what other people think. I look at physical evidence and think for myself.

Molten metal dripping out of the south tower.

Last fire put out ~3 months later. Molten metal. Melted things. Caused by a pile of burning office furniture? Molten steel? Flowing?

How about evidence of explosions? There are plenty more videos which show people reacting to explosions, have audio of explosions, and have reporters and firemen reporting explosions. Standard procedure is to test for explosives. So then is it reasonable for NIST to conclude that there were no explosions, and then to hence not perform a test for remnants of explosives in the wreckage? If I ever believe anything I see using audio/video footage taken by other people instead of using my own eye and ears... there were explosions.

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Post 19

Wednesday, February 13, 2013 - 12:37pmSanction this postReply
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Dean:

You are having way too much fun with wherever you are going with this, and I'm not going to bite.

I'm guessing it is a coping mechanism after watching the SOTU speech last night. I didn't; I watched The French Connection on DVD. Was awesome. You need to learn not to watch that stuff, it will drive you nuts.

regards,
Fred










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