The 9/11 Forum

SanderO wrote:Couldn't the motion be more complex than 1 axis rotation?

Definitely.

SnowCrash wrote:

femr2 wrote:

Hmmmm... am I the only one or does the sinusoidal profile (~1 to ~1.6s) , with increasing amplitude, look like an object rotating faster and faster? We don't see that in the video though, do we?

I think I got this wrong the first time. Maybe I'll get it wrong this time, too, but whatever, you live you learn. Rotating faster and faster in the y/z plane would increase the frequency of the sinusoid modulating g while a larger amplitude would represent a beam physically growing in length, which is of course absurd. The large amplitude is caused by ... the same mysterious thing (or mundane measurement issue) that causes the object to exceed g. Moreover, it wouldn't rotate faster and faster unless there a continuous net force acting on one end. Forum members are within their full rights to smite me if I screwed up again.

P.S.: Obviously, the one axis rotation is a simplifying assumption to aid in my own understanding.

So, what if I extracted, say, x frames and manually drew a circle around the object for each frame, the circle fitting the visible diameter of the object exactly, and then using the center of this expanding/contracting circle as the trace reference point? Wouldn't that eliminate any interference from rotation? It's a monk's work, but would it work?

SnowCrash wrote:I think I got this wrong the first time.

Yeah but smiting is so tacky. That's only done to people with usernames starting with 'p' and 't'.

Rotating faster and faster in the y/z plane would increase the frequency of the sinusoid modulating g...

Correct.

...while a larger amplitude would represent a beam physically growing in length, which is of course absurd.

Or changing its orientation and therefore projected length onto the image plane. Or changing location along the length for the source of trailing dust/smoke.

P.S.: Obviously, the one axis rotation is a simplifying assumption to aid in my own understanding.

Generally a good assumption. Euler's rotation theorem states that simultaneous rotation about two distinct axes is equivalent to rotation about a third. That is, there is only one axis of rotation at a given time. When I said "definitely" to SanderO's question, I'm referring to two things which the theorem doesn't take into account, influence of the air and wobble/precession. There may only be one axis at a given time, but it can change over time.

So, what if I extracted, say, x frames and manually drew a circle around the object for each frame, the circle fitting the visible diameter of the object exactly, and then using the center of this expanding/contracting circle as the trace reference point? Wouldn't that eliminate any interference from rotation? It's a monk's work, but would it work?

Yes. I've done it. Translucent circle in Inkscape, zoomed in large. Load frame image, send to back, select circle, Ctrl-D, move, resize, adjust, delete frame, repeat. It would eliminate rotational issues, may introduce ones of its own.

I've traced the wee blob a fair few times now...and each time, due to the fact it's a (rotating line) blob and not something consistent a "corner", is near invisible for the early motion, and video quality isn't exactly helpful...

...the results are different each time

If I got near-enough the same acceleration profile out of two different traces, I'd be fine with that and post one, but until then I'll just make a few observations...

1) Simply by watching the rotating motion and dust trail, it's seems obvious that it's not being propelled in the manner suggested by DC.

2) It is over-g in every acceleration profile I've generated. Well over at times. Nearing 2g on one at one point (yeah, crappy measurements I reckon)

3) No perspective correction. Static point extraction via a point in a different plane to the trace object...

I'll try it once more v.e.r.y.s.l.o.w.l.y. and see if I can get the trace quality up a bit...

Fascinating, thank you.

Your points:

1) Absolutely.

2) Very odd.

3) The magnitude of error can be estimated.

Good luck on tightening up the measurements. This would be folly (as compared to say, hitting the local bar or topless club) but the persistently high values make it a curiousity wanting for explanation.

You people are hard workers...

I don't believe it could be pushing from air through elevator shafts. Isn't that ignorable compared with the air resistance in free air? And it falls faster that the collapse front. There are of course some isolated 'squibs' ahead of the front but I think it is far fetched to believe a couple of them are responsible for pushing the relevant part down faster at a certain moment

Measurements error should always be taken into account, maybe with some smear methods a more
smoother curve could be made but then we need the centre of mass and the rotation. Of course it can only rotate around one axis... but that doen't of course mean that it is the axis of the object.
And if the object is not solid (or connected solid parts that have a hinge) it becomes a complex thing. Also remember that group velocity doesn't always say something about the individual speed. As long as we don't know with what we are dealing with it is hard to guess.

I checked my ancient drive for wtc2 videos and tried to fit one but didn't succeed. Here is a view which is rotated 90 degrees clockwise (seen from the top), but I'm sure there must be more out.


http://i53.tinypic.com/2yyccah.gif

Original video

http://hotfile.com/dl/131232515/49c1bee ... e.avi.html

This is 29,97 fps but seems to be progressive video. The logo pollution of Fox hides the interesting part. It is still shocking to see that everything is peeled outwards and material reaches 3 times the width of the building.

I've no conclusion at the moment...

Reaches 3 times the building width (624')? What reaches that far?... and where is that? The aspect ratio of the building was almost 7:1. Why is odd that material could fall away and land several hundred feet from the tower?

You don't believe what could be pushing air in the elevator shafts? Well let's see... suppose you have a shaft which was say 30 stories tall... 10' wide x 30' long... and the top section collapse and the material from those 30 stories, for example falls down... and some of it will fall down the shaft... why not? How much and how dense is hard to tell.. but with 30 floors above it the *stuff* plunging down inside that shaft could be quite a *plug* and of course there would be air inside the shaft... that has to be dispersed... upward? perhaps... laterally out through the elevator doors or the path of least resistance? Wouldn't the concrete pit kinda stop / direct the air a bit... it was much stronger than the shaft walls which were GWB on metal studs.

I think the explanation of the squibs telegraphing descending rubble inside the shafts and then bursting through the facade is as likely or more likely an explanation than a few placed *demo squibs*. Do you really believe that those few *squibs* are from the explosives which caused the floors to collapse 20 floors above? How does that work?

OneWhiteEye wrote:(as compared to say, hitting the local bar or topless club)

Have you not noticed the delays

Anyway...



That's about as consistent as I can get out the thing.

Speechless.

For the time being.

Rotation MUST be causing problems I rekn...

I suppose. +/- g. Once.

Now we get into an area in which the minimum angular velocity requirements for matching by rotation can be established. Take the period between 0.5 and 1.6 seconds (slightly short, rounded down), which has a peak to peak about an assumed mean of g of roughly +/- 0.9g. Where's air resistance in all this? Never mind.

0.5Lω²sin(ωt + φ) hits maxima at ωt + φ = nπ/2, we are only concerned with maxima, so 0.5Lω²(1) = 0.9g => ω = sqrt(1.8g/L) is the solution of interest. We can assume a full period over time (0.5,1.6) since that's what is apparent in the data (it may already be contradicted in the video). The equation specifies the angular velocity necessary for a given member length to produce the over/under g in the data. If the length is known, then the solution will either be consistent with or contradictory to the assumed period of rotation.

The assumed period is 1.1 sec, or a (in this case maximum) frequency of 0.9Hz. The resulting average angular velocity is 327°/sec. On the other hand, if length L is taken to be 11m, the equation above gives sqrt(1.8(9.8)/11) = 1.27 rad/sec = 72°/sec. Not consistent. Feel free to check my work, on the off chance anyone's interested - I started my day with beer and eventually caught up with some food.

The angular velocity required for the assumed length to produce the observed acceleration magnitude contradicts the angular velocity required to satisfy the assumed period in the data. Which basically is to say it seems it can't be rotation orthogonal to the viewing vector, nor rotation in a fixed plane, or the object is a lot shorter than 11m. The angular velocity matching constraints decreases by the square root of length as length increases. Rotation in a non-orthogonal plane to the camera central view angle only diminishes the magnitude, so a combination of shorter length and projected rotation could do it, IF the period were 0.9Hz. Is it? I can't tell.

Bear in mind that externally imposed forces from the air act in opposition to the direction of motion, linear or rotational, a trivial fact but necessary to keep in mind when one considers data oscillation about a mean of near g - in air. That alone raises questions.

SnowCrash wrote:All of which is interesting but OT... My OT contribution would be that (A) the nanothermite issue has not been resolved, nor has the temperature gap issue, even though Steven Jones appears to have done his best to discredit his own research by doing other things which call his scientific integrity into question. Since I was a big supporter of his, I hope I don't have to explain that this pains me. (B) The NIST reports are demonstrably false, although that doesn't prove 'CD'. (C) There is a good case for LIHOP, although unclear who pulled the strings (suspect are the military and the CIA, as usual) (D) It's a proven fact that the 9/11 Commission Report was a cover-up, in other words a conspiracy to lie.

So elements of the 9/11 Truth Movement have been successful. I do not regard anybody as the true Truth Movement except the 9/11 family members, first responders and survivors. These people are repeatedly overlooked. They are what matters here, as well as the collateral victims of the ensuing global war on terror. Poorly informed and badly educated conspiracy theorists who feel drawn to 9/11 research are irrelevant in my opinion.

Moreover, the Poteshman paper proves with mathematical certainty that there was insider trading. The counterarguments are circumstantial and cannot debunk Poteshman's statistical analysis.

Snow crash i have no wish to take this lively little thread off T.

Is this you, i tripped over this post.

Submitted by SnowCrash on Wed, 09/21/2011 - 7:08pm
Alfreda Frances Bikowsky: The Current Director of the CIA Global etc .etc

is this someone quoting you, if so where from, thanks.
http://educationforum.ipbhost.com/index ... ntry234584
post number 3