What's involved if you try to apply theory to this scenario is quoted below. I have done this kind of work in transmitters and modulators but have never been able to pin-down maths to practice.

As to Richard's comments that reading the notes referred to him made such an impression, all I can say is good luck with that approach.

Here is a link on the physics aspect of 9/11. I don't pretend to be either inclined or even able to pass an opinion on the physics aspect. People have, however, delved into that area, but probably in the way aircraft engineers study wreckage.

https://www.scirp.org/journal/paperinfo ... erid=89496"So let us include the energy dissipation into the problem of the progressive collapse of a high-rise building. Let us assume that the falling mass m=ξAρ crash into motionless mass dm=dξAρ beneath and let us use for dissipative energy the Equation (1), where mv=m and ms=dm . The assumption that both masses move after the impact together, i.e. with the same speed, determine the dissipation energy regardless the magnitude of the strain and properties of its material uniquely. Neglecting the differential of mass dm in comparison to m (i.e. assuming m+dm≈m formally), we come to the formula for the differential increment of dissipation energy due to the impact

dWpl(x)=12mv(x)2dmm+dm=12dmv(x)2

For the total amount of the dissipation energy from the beginning of the collapse until the mass reach the point x we receive

Wpl(x)=∫0xdWpl(ξ)=12∫0xv2(ξ)dm=12∫0xv2(ξ)Aρdξ(4)

The kinetic energy of falling mass in the point x can be then written in the form

Ek(x)=Ep(x)−Wpl(x)=12mv2(x)=12Aρxv2(x)(5)

where

Ep(x)=m(x)gx2=Aρgx22(6)

is the potential energy of the building above the point x to the point x. Inserting Ep(x) from (6) and x from (4) into (5), we obtain

Aρgx22−12∫0xv2(ξ)Aρdξ=12Aρxv2(x)

Consequently we have the resulting integral equation for the unknown function v(x)

xv2(x)+∫0xv2(ξ)dξ=gx2 for any x≥0(7)

together with the initial condition

v(0)=0(8)

and with the obvious requirement

v(x)>0 for any x>0 .(9)

Let us differentiate (7) with respect to x using the relation

ddx⎛⎝⎜∫0xv2(ξ)dξ⎞⎠⎟=ddx(F(x)−F(0))=dF(x)dx=v2(x)

where F(.) means a primitive function corresponding to v2(.). The obvious formal modification of (7) gives then the differential equation of collapse of a high-rise building, assuming that the columns do not resist the fall and all falling mass hits to the mass beneath, in the form, valid any for any x > 0,

dv(x)dx=gx−v2(x)v(x)x.(10)

Clearly this differential equation can be rewritten as

v(x)dv(x)dxx=gx−v(x)2

v(x)(dv(x)dxx+v(x))=gx(11)

multiplying (11) by x also as

xv(x)(dv(x)dxx+v(x))=gx2

thus after integration, using some real constan C,

12(xv(x))2=gx33+C2 ,

which yields

xv(x)=±23gx3+C−−−−−−−−√ .

Then the solution of (9) can be expressed with respect to (8) in the explicit form

v(x)=23gx3+C√x

Moreover (7) forces C = 0, which leads to the simple formula

v(x)=23gx−−−−√(12)

for the evaluation of the required velocity v(x). "

It's not just architecture.