Hans, with due respect, you seem to not consider the 2nd law of thermodynamics.
Eh, no. The 2nd Law of Thermodynamics states (among other things) that it is
reversibility that is special, not symmetry. Symmetry is omnipresent thanks to Newton's Third Law.
Having said that, few things in Nature, especially something as complex as a major building collapse, will be truly symmetric. It just depends on
how symmetric we need it to be.
WTC7 goes very straight down, careening to the south at the end. But to drop into free fall, straingt down, requires that all the vertical supports fail at the same time, or at least that a great majority of them fail in a symmetrical pattern.
There's a real danger of this becoming a semantic argument. While it didn't topple over, I don't feel that WTC 7 fell all that symmetrically. The
NIST Interim WTC 7 report which I imagine you've seen proposes a mechanism which, due to the building's construction, leads to an implosion-style collapse that might be interpreted as somewhat symmetrical. Seems to make sense to me.
WTC7 dropped in about 6.5 seconds.
Check my NIST reference, page 27. Your number is off. They give a detailed sequence of 8.2 seconds from first signs to
initiation of global collapse, so perhaps 15 seconds for the whole thing to come crashing down.
On the west end of the north face, the windows blow out in an upward sequence.
THere is a tornado like plume of smoke and debris that exits the top of the building.
Steel was recovered that had been partly evaporated.
Please cite these, I haven't heard such claims. Not saying you're wrong, just I don't know where you got this from.
The steel had a "swiss cheese" appearance from a eutectic reaction. This is when a chemical (sulfur in this case) is added to a reaction causing its melting point to lower.
If you're referring to the
FEMA steel observations, I addressed this for another newcomer in
this post. There is unarguable evidence that the melting point of the mixture was not reached, and the "eutectic reaction" (that's not standard terminology) was a chemical one. While interesting, there's no way this was a deliberate act.
It looked exactly like a controlled demolition, which we know have happened many times before, whereas complete straight down collapses of steel framed buildings have never occured for any other reason ever.
It didn't look like a controlled demolition to
PROTEC. Nor to me, either. And need I point out that the firefighters standing near the building heard it crack, watched it lean, and even measured it over the course of several hours?
Other than that, (and the Silverstein quote), not much.
This one always cracks me up. Look, even if Larry Silverstein had said
"Hey, guys, get the heck away from that place, because I've got bombs rigged on every floor -- here goes!" and pulled out a doohickey, pushed a button, and the whole tower instantly collapsed, it
still wouldn't prove that the place was demolished on purpose. Though I would be somewhat suspicious.
There's simply no evidence of bombs. There is, however, evidence of massive impact damage, huge unfought fires, and gradual material weakening leading to what NIST calls "classic progressive collapse" (page 6 of the interim reports).
