September 10, 2007

The first of this year's 9/11 posts

Eat this, truthers.

Dr Keith Seffen set out to test mathematically whether this chain reaction really could explain what happened in Lower Manhattan six years ago. The findings are published in the Journal of Engineering Mechanics.

Previous studies have tended to focus on the initial stages of collapse, showing that there was an initial, localised failure around the aircraft impact zones, and that this probably led to the progressive collapse of both structures.

Once the collapse began, it was destined to be "rapid and total."

In other words, the damaged parts of the tower were bound to fall down, but it was not clear why the undamaged building should have offered little resistance to these falling parts.

"The initiation part has been quantified by many people; but no one had put numbers on the progressive collapse," Dr Seffen told the BBC News website.

Dr Seffen was able to calculate the "residual capacity" of the undamaged building: that is, simply speaking, the ability of the undamaged structure to resist or comply with collapse.

His calculations suggest the residual capacity of the north and south towers was limited, and that once the collapse was set in motion, it would take only nine seconds for the building to go down.

This is just a little longer than a free-falling coin, dropped from the top of either tower, would take to reach the ground.


He added that his calculations showed this was a "very ordinary thing to happen" and that no other intervention, such as explosive charges laid inside the building, was needed to explain the behaviour of the buildings.

Posted by caltechgirl at September 10, 2007 09:55 PM | TrackBack

I don't buy it. 9/11 was clearly an inside job. I can see it all the way from NZ.

Posted by: Koncerned Kiwi at September 11, 2007 12:43 AM

It doesn't matter how many times we prove things like this..... There are still nut jobs that won't believe it.

Posted by: Lukie at September 11, 2007 04:50 AM


Posted by: Ken S, Fifth String on the Banjo of Life at September 11, 2007 10:14 AM

How does the mere posting of a referral to a paper not yet even published constitute a "proof" or "demolish" his critics? Where are his assumptions, his calculations, his results? Science works by creating hypotheses, testing them, having them challenged by counter-hypotheses, etc. This type of self-congratulation by those who believe the official account just shows how much we merely rely on the pronouncement of some authority rather than do the much harder work of really examining the evidence on all sides.

Posted by: bsep at September 11, 2007 10:22 AM

Well, since it got published in a well respected journal, I suspect you can do that legwork for yourself. That's how peer-review works, bsep.

Do I really need to post the actual journal article for you?

Don't come on my blog and presume to tell ME about how science works, buddy. I'd delete you without comment, but your stunning lack of understanding of what it means to be published in a leading scientific journal is amusing.

Posted by: caltechgirl at September 11, 2007 11:37 AM

bsep - you assume that the gentleman in question didn't really examine the evidence from all sides before writing the paper; that the journal in question didn't check his work; that he cited no sources (or that nobody checked them either).

Some people do blindly rely on authority. Others just as blindly dismiss authority, and routinely suspect any supporting evidence the authority gives for itself. Nothing convinces such a person becuase every new reason just becomes "part of the coverup," another suspect "fact" from the authority itself - and any third party is automatically "selling out" if they agree.

If you really prefer to rely on evidence, this is a foolish way to live.

Posted by: nightfly at September 12, 2007 10:05 AM

Recently (April 29, 2007) we had a direct, evidential example: a gasoline tanker truck hit a freeway guard rail and burst into flames - it burnt-down the entire concrete and re-bar overpass section. It was the Interstate 80 and 580 connector. There's video.
Heat from the fire, which reached temperatures estimated at up to 2,000 degrees Fahrenheit, caused the metal bolts and girders on the highway connector ramp above to melt. The overpass then gave way and collapsed.

Questioning "Authority" as an equivalent to questioning professional expertise is an example of questioning the rules of grammar as much as of simple Newtonian physics - it's as much "the willing suspension of disbelief."

Posted by: DirtCrashr at September 13, 2007 09:22 AM

the guys at popular mechanics have explored every one of these conspiracy theories and torn each one into bits. it is too bad that some people are too stupid to look at the facts and go from that but instead let their crazy gene take over and talk for them making them look stupid. dont they see all they are doing is making the conspiracy theorists look even stupider? anyone with a conspiracy theory has a motive for that theory and it usually goes back and benefits the original theorist in some way.

take a look at the popular mechanics research and if you still have a theory that has not been debunked then say something. otherwise, nobody wants to hear your uninformed crazy babble.

Posted by: Kimmy at September 13, 2007 11:24 PM

Kimmy and Caltechgirl

Ask around campus abut a guy named Richard Feynman who figured out the cause of failure for the first space shuttle. He has some wise stuff to say about science and honesty. How does WTC 7 come down, look in slow motion as the towers come down. How does gravity create the POWDER and the Flashes and the sustained collapse??? You have the name of Cal Tech to Honor and Support!!

Posted by: Thomas Spellman at September 19, 2007 02:45 PM