The views in this paper are the sole responsibility of the author (not Brigham Young University)

In writing this paper, I call for a serious investigation of the hypothesis that WTC 7 and the Twin Towers were brought down, not just by damage and fires, but through the use of pre-positioned explosives. I consider the official FEMA, NIST, and 9-11 Commission reports that fires plus damage alone caused complete collapses of all three buildings. And I present evidence for the explosive-demolition hypothesis, which is suggested by the available data, testable and falsifiable, and yet has not been analyzed in any of the reports funded by the US government. We start with the fact that large quantities of molten metal were observed in basement areas under rubble piles of all three buildings: the Twin Towers and WTC7. A video clip provides eye-witness evidence regarding this metal at ground zero: http://plaguepuppy.net/public_html/video%20archive/red_hot_ground_zero_low_quality .wmv . The photograph below shows a chunk of the hot metal being removed from the North Tower rubble about eight weeks after 9-11. Notice the color of the lower portion of the extracted metal -this tells us much about the temperature of the metal and provides important clues regarding its composition, as we shall see. Next, I invite you to consider the collapse of the 47-story WTC 7, which was never hit by a jet, as a basis for further discussion. Here is the building prior to and on September 11, 2001: WTC 7: 47 Story, steelframe building.. WTC 7 on afternoon of 9-11-01. WTC 7 is the tall sky-scraper in the back-ground, right. Seen from WTC 1 area. WTC 7 collapsed completely, onto its own footprint Now that you have seen the still photographs, it is important to the discussion which follows for you to observe video clips of the collapse of this building, so go to: http://911research.wtc7.net/talks/wtc/videos.html Click on the three photos at the top of this web-site page in order to see the videos of the collapse of WTC 7. It helps to have sound. Then consider a video close-up of the same building (SW corner) as its demise begins: http://st12.startlogic.com/~xenonpup/Flashes/squibs_along_southwest_corner.htm What did you observe? Symmetry: did the building collapse straight down (nearly symmetrically) – or did it topple over? Speed: How fast did the building fall? (Students and I measure less than 6.6 seconds; time it!) Smoke/debris-jets: Did you observe puffs of smoke/debris coming out of the building? Please note for yourself the sequence and fast timing of observed puffs or “squibs.” Note that reference to web pages is used in this paper due largely to the importance of viewing motion picture clips, thus enhancing consideration of the laws of motion and physics generally. High-quality photographs showing details of the collapses of WTC 7 and the WTC Towers can be found in books (Hufschmid, 2002; Paul and Hoffman, 2004), magazines (Hoffman, 2005; Baker, 2005) and at http://911research.wtc7.net/wtc/evidence/photos/collapses.html. My reasons for advancing the explosive-demolition hypothesis while challenging the “official” fire-caused collapse hypothesis are these: 1. There are several published observations of molten metal in the basements of all three buildings, WTC 1, 2 (“Twin Towers”) and 7. For example, Dr. Keith Eaton toured Ground Zero and stated in The Structural Engineer, ‘They showed us many fascinating slides’ [Eaton] continued, ‘ranging from molten metal which was still red hot weeks after the event, to 4-inch thick steel plates sheared and bent in the disaster’. (Structural Engineer, September 3, 2002, p. 6; emphasis added.) The observation of molten metal at Ground Zero was emphasized publicly by Leslie Robertson, the structural engineer responsible for the design of the World Trade Center Towers, who reported that “As of 21 days after the attack, the fires were still burning and molten steel was still running.” (Williams, 2001, p. 3; emphasis added.) Sarah Atlas was part of New Jersey's Task Force One Urban Search and Rescue and was one of the first on the scene at Ground Zero with her canine partner Anna. She reported in Penn Arts and Sciences, summer 2002, ‘Nobody's going to be alive.' Fires burned and molten steel flowed in the pile of ruins still settling beneath her feet. (Penn, 2002; emphasis added.) Dr. Allison Geyh was one of a team of public health investigators from Johns Hopkins who visited the WTC site after 9-11. She reported in the Late Fall 2001 issue of Magazine of Johns Hopkins Public Health, "In some pockets now being uncovered they are finding molten steel.” Further information on the subject is available at http://globalresearch.ca.myforums.net/viewtopic.php?p=11663. A video clip provides eye-witness evidence regarding this metal at ground zero: http://plaguepuppy.net/public_html/video%20archive/red_hot_ground_zero_low_quality .wmv . The observer notes that the observed surface of this metal is still reddish-orange some six weeks after 9-11. This implies a large quantity of a metal with fairly low heat conductivity and a relatively large heat capacity even in an underground location. Like magma in a volcanic cone, such metal can remain hot and molten for a long time -once the metal is sufficiently hot to melt in large quantities and then kept in an underground location. Thus, molten metal was repeatedly observed and formally reported in the rubble piles of the WTC Towers and WTC 7, metal that looked like molten steel. Scientific analysis, using for example X-ray fluorescence, would be needed to ascertain the actual composition of the molten metal. I maintain that these observations are consistent with the use of the hightemperature thermite reaction or some variation thereof, used to cut or demolish steel. Thermite is a mixture of iron oxide and aluminum powder. The end products of the thermite reaction are aluminum oxide and molten iron. So the thermite reaction generates molten iron directly, and is hot enough to melt and even evaporate steel which it contacts while reacting. Use of sulfur in conjunction with the thermite should accelerate the destructive effect on steel, and sulfidation of structural steel was indeed observed in some of the few recovered members from the WTC rubble. (See http://www.911research.wtc7.net/wtc/evidence/metallurgy/index.html.) On the other hand, falling buildings (absent explosives) have insufficient directed energy to result in melting of large quantities of metal. The government reports admit that the building fires were insufficient to melt steel beams -then where did the molten metal come from? Metals expert Dr. Frank Gayle (working with NIST) stated: 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. (Field, 2005; emphasis added.) None of the official reports tackles this mystery. Yet this is evidently a significant clue to what caused the Towers and WTC 7 to collapse. So I would very much like to see an analysis of the elemental composition of the metal, and could do this myself if a small sample were made available according to scientific courtesy. Any reader who knows of chemical analyses or even photographs of this molten metal found below the rubble piles of WTC 1, 2 and 7 is invited to speak out and contact the author. This could lead to an experiment crucis. Even without a direct elemental analysis, we can rule out some metals based on available data. The photograph in the introduction shows a chunk of the hot slag being extracted at ground zero. The hottest portion of the chunk is the lower portion, which was deepest down in the slag, and the metal is seen to be yellow-hot, certainly above cherry-red hot. The following table (see http://www.processassociates.com/process/heat/metcolor.htm) provides data regarding the melting temperatures of lead, aluminum, structural steel and iron, along with approximate metal temperatures by color. °F °C K Lead (Pb) Melts Faint Red Blood Red Aluminum Melts Medium Cherry Cherry Bright Cherry Salmon Dark Orange Orange Lemon Light Yellow White Structural Steel Melts Iron Melts 621 93