There was a pretty good show on PBS explaining the design and construction of the towers, and how when the upper floors started collapsing the lower floors could not support the weight and the fasteners the structural support points then sheared under the heavy loads of the upper floors falling down upon them. It was an outstanding job by PBS and some of the key engineers of the original project were interviewed.
I can also tell you from my perspective as a mechanical engineer that I or any of my colleagues would never ever comment publicly or in writing on a subject that was not in ones area of expertise. This individual who is supposidly a Physics professor probably knows very little of structural design of buildings. For him to use his knowledge of Physics to try to qualify himself as a valid conspiracy theorist on building demolition is akin to a podiatrist attempting to perform heart surgery. Hey there both doctors right.
I've seen a detailed summary on the world trade center collapse from a symposiom by the American Society of Mechanical Engineers. They got into everything from fuel source burn temperatures, fire temperatures, component failures etc.. and I suspect that the American Society of Civil Engineers has studied this failure extensively as well. I would trust judgements by the ASME or ASCE long before I could ever give a conspiracy theorist the time of day. But most people will find it much easier to side with the simple to understand conspiracy theories than muddle through excrutiantingly detailed engineering reports.
I give the BOZO from this university two thumbs down. If he actually does exist though, and this is not just some made up hoax on the internet, I strongly suspect he never had any professional credibility to begin with, so probably felt he had none to lose when he wrote this garbage.
If you really want some good info on this I suspect that searching through the ASME or ASCE information on the world trade center collapse a must better place to start. Unless of course you believe they also might be involved in a massive coverup.
Ed