
15 Years Later: on the physics of high-rise building collapses [pdf] - 2a0c40
http://www.europhysicsnews.org/articles/epn/pdf/2016/04/epn2016474p21.pdf
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woah
There are several half-formed complaints from people who did not read the
article in this comment thread. I'm guessing that the commenters are having a
knee-jerk reaction to the fact that there are a lot of conspiracy theorists
out there who think that the US government did 9/11 etc.

This article is not about that. It revisits a disaster (the collapse of WTC7)
which appears to have happened under very unique circumstances. If the
accepted explanation is correct, WTC7 is the only high rise to ever have
collapsed from fire, and the collapse resulted from a long string of
coincidences. The article is a critique of this analysis.

~~~
lb1lf
>...and the collapse resulted from a long string of coincidences.

-Most, if not all spectacular, unexpected events are the result of a long string of coincidences. Otherwise, they'd be common occurrences.

~~~
loup-vaillant
That would work with one building. A long string of coincidences (failures
upon failures…), such as the ones that causes some big server outage, or
blackout, or plane crash, could have been a good explanation for the fall of
one building.

Here however the "string of coincidences" hypothesis would have to apply
pretty much simultaneously to _three_ buildings, one of which wasn't even hit
by a plane.

No. freaking. way. That's just too damn improbable.

~~~
jcranmer
You're ignoring correlation. The twin towers are, for almost all purposes,
virtually identical, and experienced largely identical scenarios. For them to
behave differently under such circumstances would be less extraordinary than
for them to behave similarly.

To my knowledge, the twin towers are the only buildings in history to have
been hit with a four-engine plane full of fuel (El Al Flight 1862 apparently
had only two engines left when it struck the apartment building. Note that the
building fully collapsed at point of impact). Again, to my knowledge, with WTC
7, they were the only high-rises to have experienced serious, out of control
multi-floor fires for hours after receiving major structural damage--Deutsche
Bank received serious damage but no fires so far as I can tell.

If 100% of similar structures in similar circumstances have failed in a
similar manner, is that improbable?

~~~
loup-vaillant
Then we're veering off the "multiple coincidences" hypothesis, to a much more
probable theory.

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lb1lf
I find the conspiracy theories surrounding 9/11 somewhat amusing.

With regards to controlled demolition - how on earth would anyone be able to
rig the buildings for controlled demolition without anybody noticing?

And why use slow-acting thermite when shaped charges would be more efficient
and harder to detect (both before, during and after the event)

Not to mention - how have They(tm) been able to keep their conspiracy under
wraps?

Seriously - you pull off a massive gig like this, hardly the work of a couple
of lone wolves - and no-one talks?

~~~
colejohnson66
It's best not to think about it. Conspiracy theorists have a tendency to take
confirmation bias to an extreme. If you provide a counter argument, they don't
respond to that argument, they attack your character by "realizing" that
you're part of the conspiracy too.

~~~
20yrs_no_equity
Isn't calling them "conspiracy theorists" itself an attach on their character?

Personally, I like to play devils advocate, and I'm curious about what
happened on 9/11\. It doesn't add up for me. So I have taken the "conspiracy
theorist" side several times... I don't see people making arguments against
the theorists data.

I see the same common fallacies, most often variations of appeal to authority.
"Popular science debunked that" for example in response to an argument that
Popular Science didn't address.

"If it were a cover up it would have gotten out" in response to people
pointing "it getting out" is my favorite, of course. Sort of a "I don't
believe it, therefore it can't be right". Not sure what fallacy that is.

~~~
colejohnson66
> Isn't calling them "conspiracy theorists" itself an attach on their
> character?

I've never thought of it like that. For me, I've always looked at it as a
literal definition. They theorize that there is a conspiracy. However, I guess
it could be seen as an attempt on someone's character because it does have a
negative connotation.

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Tycho
It doesn't talk much about the damage from impact and also jet fuel.

~~~
woah
This is about WTC7, which was not hit by a jet, and did not come into contact
with jet fuel. It's the only skyscraper ever to have collapsed from fire.

~~~
jcranmer
... after getting a front-row seat to two massive buildings collapsing. There
was some serious damage to the building from the collapse of the towers, which
was after all responsible for starting many of the fires.

Also, as far as I'm aware, almost all skyscrapers with major fire damage are
largely uncontrolled fires on one or two floors, rather than uncontrolled
fires throughout the entire building.

Also: [http://www.sfgate.com/bayarea/article/Tanker-fire-
destroys-p...](http://www.sfgate.com/bayarea/article/Tanker-fire-destroys-
part-of-MacArthur-Maze-2-2575285.php) \--that's a steel structure (overpass,
not a skyscraper) being collapsed entirely due to an out-of-control fire (due
to a crashed gasoline truck).

~~~
20yrs_no_equity
I know paper burns at fahrenheit 451 (thanks Ray Bradburry)... what
temperature does jet fuel burn at? Or that gasoline truck? I presume it's a
much higher temperature.

The jet fuel that hit the twin towers was mostly expelled in massive
fireballs, with some of it draining into the towers.

I don't see a reason to believe WTC 7 was saturated in jet fuel. So WTC 7 was
a paper & wood and fabric fire, right?

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xpaqui
> Meanwhile, unreacted nano-thermitic material has since been discovered in
> multiple independent WTC dust samples [13]

[http://www.911research.wtc7.net/mirrors/bentham_open/ActiveT...](http://www.911research.wtc7.net/mirrors/bentham_open/ActiveThermitic_Harrit_Bentham2009.pdf)

Suspicious Indeed.

------
nwp
FYI: Truther article

~~~
woah
Is an article that comes to a conclusion different than the one you believe
automatically false? That seems to be your only complaint.

~~~
jcranmer
Conspiracy theorists (in general) have been known to make stuff up, and non-
experts who believe in them can easily parrot this stuff thinking it's true. A
great example of this in history is the "Magic Bullet Theory" of JFK's
assassination, which holds that the single bullet is false because the bullet
would have had to make sharp turns to get to its next target, which is almost
entirely based on made-up positions in a fake film.

Thus, for an article which is espousing that the towers came down only via
controlled demolition, it is necessary to find independent sources of all
facts mentioned, even ones as pedestrian as the expected weight of a floor of
a building. (I haven't done the math myself, so I hold no opinion as to
whether or not the numbers in the article are correct).

~~~
20yrs_no_equity
Your characterization of the Magic Bullet Theory is inaccurate. The error is
in not realizing the car was of an unusual geometry (I believe JFK was
elevated, and the seats were different widths apart between the front and the
back- unusual for cars of the time.) So assuming the car was normal, and all
the seats were the same distance apart and the same height, you would need a
magic bullet. Applying deeper understanding of the setup of the car accounts
for that, reducing it to the improbable bullet theory. That doesn't mean they
were wrong, that means they didn't have access to the car to do direct
measurements. When the government locks down the evidence (or in the case of
9/11 immediately ships it off to china, before the investigation begins,
literally shipping buildings across the ocean to be recycled) it's not the
fault of the conspiracy theorists if they come up with wrong hypothesizes when
denied access to the evidence every legitimate researcher should have access
to.

Regarding "fake film" you seem too be referring to Oliver Stones "JFK" which
is not the source of the Magic Bullet Theory, or any of the theories there, it
is merely a collection of the theories prominent at the time, and then
fictionalized.

