The BBC has a rather interesting article about a paper by a UK structural engineer on the collapse of the towers:
An analysis of the World Trade Center collapse has challenged a conspiracy theory surrounding the 9/11 attacks.
The study by a Cambridge University, UK, engineer demonstrates that once the collapse of the twin towers began, it was destined to be rapid and total.
One of many conspiracy theories proposes that the buildings came down in a manner consistent with a "controlled demolition".
The new data shows this is not needed to explain the way the towers fell.
For those interested in the qualifications of this scientist, they are found here:
BA (First Class) Engineering Tripos, University of Cambridge (1993) MA,
University of Cambridge (1997)
PhD, University of Cambridge (1997)
Dr Seffen is a Lecturer at Cambridge University Engineering Department (CUED). He is a member of the Civil, Structural and Environmental Engineering Division (Division D). He is also an Official Fellow of Corpus Christi College.
Please compare them to the members of the group Architects and Engineers for 9/11 Truth, who still lack a single real live structural engineering PhD, and have failed to produce a single academic paper on this subject.
Thanks to John in the comments for pointing this article out.