Soon after Mr. Jones posted his paper online, the physics department at Brigham Young moved to distance itself from his work. The department released a statement saying that it was "not convinced that his analyses and hypotheses have been submitted to relevant scientific venues that would ensure rigorous technical peer review." (Mr. Jones's paper has been peer-reviewed by two physicists and two other scholars for publication in a book called 9/11 and American Empire: Intellectuals Speak Out, from Olive Branch Press.)
The Brigham Young college of engineering issued an even stronger statement on its Web site. "The structural engineering faculty," it read, "do not support the hypotheses of Professor Jones." However, his supporters complain, none of Mr. Jones's critics at Brigham Young have dealt with his points directly.
While there are a handful of Web sites that seek to debunk the claims of Mr. Jones and others in the movement, most mainstream scientists, in fact, have not seen fit to engage them.
"There's nothing to debunk," says Zdenek P. Bazant, a professor of civil and environmental engineering at Northwestern University and the author of the first peer-reviewed paper on the World Trade Center collapses.
"It's a non-issue," says Sivaraj Shyam-Sunder, a lead investigator for the National Institute of Standards and Technology's study of the collapses.
Ross B. Corotis, a professor of civil engineering at the University of Colorado at Boulder and a member of the editorial board at the journal Structural Safety, says that most engineers are pretty settled on what happened at the World Trade Center. "There's not really disagreement as to what happened for 99 percent of the details," he says.
Thomas W. Eagar is one scientist who has paid some attention to the demolition hypothesis — albeit grudgingly. A materials engineer at the Massachusetts Institute of Technology, Mr. Eagar wrote one of the early papers on the buildings' collapses, which later became the basis for a documentary on PBS. That marked him for scrutiny and attack from conspiracy theorists. For a time, he says, he was receiving one or two angry e-mail messages each week, many accusing him of being a government shill. When Mr. Jones's paper came out, the nasty messages increased to one or two per day.
So Mr. Eagar has become reluctantly familiar with Mr. Jones's hypothesis, and he is not impressed. For example, he says, the cascade of yellow-hot particles coming out of the south tower could be any number of things: a butane can igniting, sparks from an electrical arc, molten aluminum and water forming a hydrogen reaction — or, perhaps most likely, a spontaneous, completely accidental thermite reaction.
Occasionally, he says, given enough mingled surface area, molten aluminum and rust can react violently, à la thermite. Given that there probably was plenty of molten aluminum from the plane wreckage in that building, Mr. Eagar says, it is entirely possible that this is what happened.
Others have brought up this notion as well, so Mr. Jones has carried out experiments in his lab trying to get small quantities of molten aluminum to react with rust. He has not witnessed the reaction and so rules it out. But Mr. Eagar says this is just a red herring: Accidental thermite reactions are a well-known phenomenon, he says. It just takes a lot of exposed surface area for the reaction to start.
Still, Mr. Eagar does not care to respond formally to Mr. Jones or the conspiracy movement. "I don't see any point in engaging them," he says.
Hence, in the world of mainstream science, Mr. Jones's hypothesis is more or less dead on the vine. But in the world of 9/11 Truth, it has seeded a whole garden of theories.
