In September 2005, Professor Steven E. Jones from the Department of Physics and Astronomy at Brigham Young University released a paper on the University web site titled Why Indeed Did the WTC Buildings Collapse? [11]; in the paper Jones expounds on a controlled-demolition theory for 1, 2, and 7 WTC. The paper was presented to an audience from BYU and Utah Valley State College on September 22, 2005.

Jones and other dissidents raise a number of opposing claims: 1. that NIST is part of the federal government and therefore can not be an objective witness in an alleged government conspiracy; 2. that no steel building has ever collapsed from fire before or since 9/11 [12]; 3. that the building fell at nearly free-fall speed.

They observe that frame-by-frame video of the collapse shows features which are classic of controlled demolition and cutting charges, and otherwise inexplicable under the usual explanation:

• "Squibs", or large spherical puffs of smoke, emerge from the buildings in synchronization, from floors below the collapse, and in advance of the collapse. Air pressure is not a viable cause for these, but they are a classic phenomenon associated with controlled demolition. They occur at sub-0.2 second intervals, too rapidly to be air explusion from collapsing floors. They appear to be described as going up WTC 7 (down in WTC 1 + 2) although the collapse was downward. Upward charge sequencing is common in controlled demolition.
• Bright flashes are visible, sometimes even through the smoke, on floors significantly below the impact. "Halos" around these on film and the consistent appearance when studied microscopically, determine that they are not artifacts, but real events recorded on film.
• Concrete is ejected as fine pyroclastic powder. But in a pure impact and collapse scenario it would be ejected as shattered blocks of rubble. Powder ejection in bulk is characteristic of explosive-initiated demolition.
• Material is ejected from the collapse in a manner described as classic for controlled demolition, but inconsistent with impact and collapse without further explosives.
• The collapses were symmetrical, that is, the buildings collapsed into their own footprints. But an airplane has extremely high momentum, and the collapse from impact would be extremely likely to be assymetrical. Symmetrical collapse is a hallmark of controlled demolition. Symmetric collapse is so difficult to achieve that "only a handful of demolition companies in the world will attempt it" (Harris, 2000). Yet all three buildings collapsed this way.
• FEMA admit the standard hypothesis is extremely weak: "Although the total diesel fuel on the premises contained massive potential energy, the best hypothesis [fire/damage-caused collapse] has only a low probability of occurrence." (FEMA, 2002, chapter 5)
• Molten metal was found, in a manner that was not possible to explain under normal assumptions, since the collapse and fire would not have been capable of that impact at the locations they were found. (Structural Engineer, September 3, 2002, p.6 and Williams, 2001, p.3 and Penn, 2002) "Your gut reaction would be the jet fuel is what made the fire so very intense, a lot of people figured that's what melted the steel. Indeed it did not, the steel did not melt." (Metals expert Dr. Frank Gayle, working with NIST: reported by Field, 2005) "Fire and the structural damage... would not explain steel members in the debris pile that appear to have been partly evaporated", Dr. [Jonathan] Barnett said. (Glanz, 2001). Fires involving known materials on the scene could not generate temperatures anywhere near the 3,000ºC needed to evaporate steel. However, thermite, RDX and other demolition explosives could easily cut through the steel support columns simultaneously and would easily reach these temperatures. "NIST determined that there was no evidence that any of the samples had reached temperatures above 600 ºC." (NIST, 2005, pp. 176-177). "[T]he buildings should have easily withstood the thermal stress caused by... burning" (Ryan, 2004).
• The observations suggest that the building's steel core somehow gave way first (Glanz and Lipton, 2002), and the anomaly of how exactly the massive core failed was raised by the FEMA report (FEMA, 2002, ch. 2) yet not solved in any official report (FEMA, 2002; Commission, 2004; NIST, 2005). It was not even raised in the final NIST report (NIST, 2005).
• The floors collapse at near-freefall speed. This is inconsistent with the model of the proposed collapse, where each floor hits the one below, and is slowed both by repeated impact (conservation of momentum) and by the massive central column or its remains. The implication is that the central column is somehow being cut or removed ahead of the impact too.
• The South Towers top 34 blocks rotate and fall away as a unit - and then appear to turn mostly to powder in midair. This is unfeasible for a pure impact and collapse scenario but possible if explosives are involved. "[The Final NIST 9-11 report] does not actually include the structural behavior of the tower after the conditions for collapse initiation were reached." (NIST, 2005, p.80)
• Witnesses reported explosions in the base of the buildings, far below the impact:
  • Firemen and others described flashes and explosions in upper floors near where the plane entered, and in lower floors of WTC 2 just prior to its collapse, far below the region where the plane had struck the tower (Dwyer, 2005)
  • At the start of the collapse of the South Tower, Fox News reported, "There is an explosion at the base of the building - white smoke from the bottom - something happened at the base of the building! Then another explosion." (De Grand Pre, 2002)
  • A firefighter reported: "[We] thought there was like an internal detonation, explosives, because it went in succession, boom, boom, boom, boom, and then the tower came down -- It actually gave at a lower floor, not the floor where the plane hit." (Dwyer, 2005)

The above is summarized from observations in Steven Jones' draft paper.