Congrats to Dr. Hulsey and the University of Alaska! Since 9/11, several steel-structure skyscrapers around the world have burned for 15-20+ hours and NONE of them collapsed. WTC7 was NOT hit by a plane. It was a 47-story steel-structured skyscraper which collapsed, symmetrically, at free-fall speed into its own mass and footprint and created a pyroclastic cloud which can only be produced by two things; volcanoes and controlled demolitions.

I applaud Dr. Hulsey's courage to delve into this astonishing event. Judging by the ignorance of the science-deniers on this thread, he put intellectual curiosity and science ahead of his reputation. There is only one explanation for the collapse of WTC7, and that is controlled demolition. Once that is established, perhaps the UAF Institute of Northern Engineering could look into WTC1 and WTC2. Those steel-structured buildings also collapsed at free-fall speed, symmetrically into their own mass and footprint also creating a pyroclastic cloud.