brief description: There are many theories surrounded how and why the two towers fell, the most popular being that it was a controlled demolition organized by the Government. These claims are backed with a plethora of 'evidence' that can easily confuse and convince people. Below is a list of their more popular claims. theory and evidence evidence against free fall the buildings fell at 'near free fall' speed, falling without resistance as the floors had been destroyed beneath. there are 2 distinct problems with this theory. (i) it is impossible to tell the when the collapse ends due to dust clouds, so any time given is not exact. (ii) as this video clip shows, debris (which is falling at 'free fall' speed) to the left and right of the tower is falling far more rapidly than speed of the collapsing building. squibs from controlled demolition smoke and debris can be seen exploding from windows below the collapse. these are claimed to be 'squibs' caused by explosives, seen here. there are many problems with these 'squibs' being from explosives bringing down the WTC. (i) any explosion powerful enough to destroy the central cores would smash more than just 1 window per level. (ii) controlled demolitions detonate their explosives simultaneously on every floor (on a vertical axis). wtc has one explosion, not on every floor, going off one at a time. (iii) in controlled demolitions all floors fall together immediately after the explosion. in wtc the squib goes off yet the building does not immediately give way.