Niels Harrit, Professore di Chimica all'Università di Copenhagen per 37 anni, ha scritto un articolo sul WTC7 per il quotidiano Danese "Information Dagbladet", che già l'anno scorso aveva pubblicato un articolo sull'11 Settembre dopo il noto sondaggio di Zogby.

The seventh tower

WTC7 was built around a core of 24 massive steel columns, connected by an asymmetric pattern of steel cross beams. The building periphery was made up of 57 smaller columns. There was enough redundant capacity in the design to handle loads several times greater than foreseeable loads from hurricanes or earthquakes, etc.

The collapse of the nearest tower, WTC1, caused damage to the lower floors in the southwest corner of WTC7. Building debris from the high tower and large amounts of dust poured in through the windows. Randomly distributed fires then broke out on other lower floors in the building. One of the other buildings in the complex, WTC5, was much more seriously damaged by the collapse of WTC1, but the rest of the structure remained standing.

WTC7 did not. After the building had smouldered for seven hours, it collapsed, perfectly symmetrically. It was quite literally levelled, and ended up as a pile that was basically confined to its footprint. The process took 6.4 seconds, which is equivalent to "free fall". If you had stood on the 47th floor and thrown an apple out the window at the exact moment the collapse began, your apple would have hit the ground at the same time as the roof.

How could it happen?
In the hours following the airplane strikes on the two towers, a global myth began to spread that the World Trade Centre collapsed due to fire and mechanical damage.

The only problem is that no steel structure has ever before collapsed due to fire, it is historically unprecedented. Over 400 cases of fire in that type of skyscraper are known prior to 2001, and none have collapsed. Not one.

[...]

There is therefore no scientific precedent that justifies pointing to commonplace fires as a possible explanation for the collapse of WTC7.

Surely then, the explanation must be that the enormous weight of the debris from the collapse of towers WTC1 and WTC2 damaged the building or its foundations to such an extent that it collapsed?

After a delay of seven hours?

The WTC collapse
When tall buildings are exposed to extreme earthquakes, they tip over as they fall. If there is enough room, they sometimes tip right onto their sides. WTC7 collapsed exactly like a house of cards. If the fires or damage in one corner had played a decisive role, the building would have fallen in that direction. You don't have to be a woodcutter to grasp this.

[...]

How did WTC7 collapse? We are not asking 'why'. This is no conspiracy theory. There is no burden of proof on us. Some extremely simple observations have been made, and we want to hear an official explanation that is consistent with elementary physics and chemistry, and common sense.

If you want to investigate the conditions described above, you won't find anything in the media. But Google something like 'WTC7' and you will find a flood of information. There are tens of thousands of people who have a feeling something is wrong.

But there is not a word about it in the media.