Quote from Maverick1:
Thanks for your post. Since none of us have the time/resources/means to recreate an experiment of that magnitude for the sake of using the scientific method (formulation, observation, recording, testing etc) to back our arguments, it seems to me that we are reduced to using common sense and probabilities.
Thank you, too, for your response.
Experiment:
No Way!
An experiment on the required scale is completely out of the question.
But I think it is conceivable to try to do a numerical calculation of maximum
pressures and interfloor air flows that could be achieved in the tower
collapses, taking into account the actual geometry of the towers, as well as
what we know about the time scales involved.
That calculation would give a better sense whether my, and Turok's much better
elaborated, discussion of a scenario for production of the few `squibs' that
are seen
well below the collapse front is at least
conceivable,
or is in fact theoretically ruled out. That's all that I meant by backing up
my speculation.
Ultimately one wants to write some differential equations whose solution will
give the air pressure over time in the uncollapsed portions of the building,
possibly given varying assumptions about what doors are open and closed.
But the real starting point, I think, is just to get rough estimates of the
way air pressure evolves with time for the air contained within a single
collapsing story, given that you know how the volume of the region evolves up
until the windows fail.
With those initial numbers one could begin to consider how much of the air
might be driven downwards in the collapse of each successive story, versus how
much would go out of the windows when they fail.
It's obviously a dynamical question, with various, and varying timescales
involved -- the whole collapse takes place within a time which is the same
order of magnitude as the free fall time, though it is of course,
larger than the free fall time, as it must be -- and this gives an
average collapse time for each individual story in the building, but the
collapse also accelerates as time proceeds.
One needs to know the strength of various materials such as the window glass;
the actual geometry and resistance coefficients of the possible air flow paths
running between floors in the trade center, and undoubtedly many other factors
which I haven't yet considered in order to attempt to give any realistic
numbers.
All of this is hard to do. I'ld certainly want to talk to a structural
engineer familiar with the towers before even starting.
My
intuition is that surprisingly high pressures may indeed be
achievable on floors near to the collapse front, and that if a path exists for
air to flow to very much lower floors, those pressures could well be
transmitted downwards ahead of the collapse.
But, to be quite frank: since I would not, not even if my proposed explanation
were shown to be impossible, and
NO other possible explanation were to
be found -- consider the appearance of a few random dust plumes on floors well
below the collapse front, which seem to you and to others to look like those
that might be produced by explosive devices, to be the smoking gun that
establishes beyond a reasonable doubt that there were explosive devices
involved, I'm simply not going to make the attempt in the first place.
The answer that one should ask oneself is one of a conditional probability:
What are the odds that air pressure would only affect a few select lower floors while bypassing every one of the 20 or so floors in between given (a) the countless descriptions of explosions from people both inside and outside the building and (b) the projectiles uncanny resemblance to squibs in a typical demolition
Well, I
could simply respond that the best
a posteriori estimate
of the probability of occurrence of an event, given that the event has
occurred, is always equal to 1. But that would be possibly impolite.
You clearly consider the number to be closer to 0.
Of course, I have already admitted above that I have no way of making such a
probability calculation in the first place, so I'm certainly not going to play
the game, given that I don't have a precise mechanism to work with
My answer that the probability is equal to 1 is naturally contingent on my
assumption that there were no explosive squibs involved, and that mine was the
actual mechanism for producing the dust plumes. My intent was only to
establish a
possible alternative explanation for the fact that dust
plumes or `squibs' appear some 20 floors (or was it 30 or 40 floors) below the
collapse front, at some time during the collapse. If I
had completed
that task then I'ld be more than satisfied.
I submit that in fact, the relevant conditional probability calculation for
you, if you hold to the conspiracy theory, is the one for the probability that
there were explosive `squibs' involved in the first place.
And for that question I personally would say you need to look to other
determining evidence ... there would have to be quite a few of these `squibs,'
in order to collapse the towers. Not just the few apparently visible on lower
floors whose appearance you, very correctly in my view, find to be puzzling.
I should say that hundreds might be required at a minimum, in order to cut the
support at a critical point in the building and initiate a collapse. And
then, why is there no evidence at all of remnants of detonators, tape,
explosive materials, etc., such as I expect would be
easily found in
the case of an actual controlled demolition?
Recall, too, that in the 1993 terrorist attack there was no difficulty
whatsoever in detecting explosives.
These `squibs' would need to have been emplaced and wired over a fairly
significant period of time, with the work remaining concealed from a very
large number of potential witnesses. I think a total of about 100,000 people
worked in the towers in total, with around 50,000 being present on average in
a typical 24 hour period. Granted, not all of these people would have had the
possibility of seeing what was going on. But still, there would be a lot of
potential witnesses, and it seems very likely that at least some of these
would have been both well informed enough, and in a position to know something
wrong was taking place.
One can certainly insist that, nevertheless, all of this might have been
achieved, but it seems that if things did happen this way, then there must at
least have been a very extensive conspiracy among the people who carried it
out, and not a single person involved ever spoke up about it, and no hint
of the conspiracy has come to light.
All of this seems inherently very unlikely to me.
So in the absence of real physical evidence for explosive devices, and in the
presence of what seems to be a convincing standard story of the mechanism for
the tower collapses, which is certainly at least
generally consistent
with the observed facts, I conclude that the standard story best fits the
evidence.
In addition, you dismiss the witnesses' accounts wholesale, but is it fair to
do so when there is a preponderance of such descriptions of explosions? Would
you completely ignore such testimony if you were in a juror in court?
Naturally I would consider what the witnesses had to say if I were a juror in
court.
I don't mean to, and I do not in fact, dismiss the eyewitness accounts
wholesale: I simply consider that their accounts are not
directly
probative of the existence of explosive devices, and that there may be other
explanations for what they heard and saw. At best, eyewitness reports of what
was heard might be strongly suggestive of explosive devices, only rarely could
they be considered probative on their own in a case like this.
The reasons are that the scale of this scene is almost unimaginably large in
comparison to any one person, and the relevant time scale for hearing the
explosions of the `squibs' in question is relatively short: there are
certainly not much more than 20 seconds each during which the collapse of each
tower takes place. During these seconds, there was certainly a
tremendous amount of other noise being produced. This was a very
extreme situation. All of that tends to lead to people's accounts being
confused, especially if they are not experienced emergency workers.
If the suggestion is that there were lots of other, say much larger explosions
that weakened the structure, taking place independent of the `squibs,' and
previous to the actual collapse, and that it was these that were overheard by
witnesses, then I think that the conspiracy theory of the collapse is becoming
a bit too overengineered ... too baroque to be likely.
It's always necessary in any case to consider the weight that should be
attached to any witnesses' testimony in the light of the quality of the
opportunity they had to observe the events that they testify about, as well as
any special knowledge and experience that they might have, or might need to
have to draw conclusions. How many were knowledgeable about explosives, for
example?
If all of the testimony were combined with
solid physical evidence of
the explosives in question, then I think it would be a very different matter.
Cheers!
