by Sid Deutsch
As Prof. Greene writes, "Lately, however, string theory has come in for considerable criticism." Specifically, here are two recent books by physicists that reveal, in their titles, that they represent “considerable criticism”: "The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next," by Lee Smolin , and "Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law," by Peter Woit . Both of these 2006 books are reviewed by George Johnson in the September 2006 Scientific American. One may regard the Smolin-Woit books as self-criticism from a Physics Department.
I am an Electrical Engineer. The major difference between engineers and physicists is that engineers are realistic because they design and supervise the construction of edifices that have to survive. People like Greene get into trouble because "We now have more than 20 years of painstaking research, filling tens of thousands of published pages of calculations, which attest to string theory's deep mathematical coherence," but nothing resembling a realistic result has come forth from all of this self-aggrandizement.
Here is some more nonsense from the physics department: A vacuum is not nothing: it is full of a chaotic mixture of subatomic particles being created and destroyed. The electrical engineering department (actually, Sid Deutsch), says "Nonsense. A vacuum consists of aether particles, the medium that transmits light waves, analogous to the way air transmits sound waves. The vacuum has specific, measurable values of permeability and permittivity; these determine the speed of light waves, analogous to the way density and elasticity determine the speed of sound waves" .
The departments of physics, astronomy, and cosmology have discovered "Dark Matter": The Universe is filled with a mysterious, so far undetected Dark Matter. We know it is here because Dark Matter is gravitationally attracted to the stars, and substantially alters their motions. This is an understatement: The Dark Matter is a “cloud” that fills all of space, but the space between stars is so vast that, when you add it all up, the Dark Matter is, very approximately, ten times as heavy as the stars themselves. But this description exactly fits the aether! Einstein (and others) abandoned the aether because it was not possible to measure it. The reason is that the aether is gravitationally attracted to the earth (and to every massive galactic object). Therefore, it moves with the earth, much like the earth’s atmosphere of gas. To detect the aether, we need an apparatus that can measure the speed of light in three mutually perpendicular directions (left-right, front-back, up-down); taken aboard a space vehicle, it would yield a vector that represents the motion of the aether with respect to the vehicle. I believe that today we have the technical capability to construct such a speedometer. It has to be accurate to within a few meters/second.
Every galaxy has its own cloud of Dark Matter/Aether Particles.
More nonsense: The Physics Dept. offers a model of the Universe that began with a Big Bang: It was something the size of a grapefruit. They unscientifically (because it cannot be proved) offer that the laws of physics were different. (Some go so far as to say the Universe began with a "point.") The electrical engineer Sid Deutsch says "Alright, perhaps the Universe started with a Big Bang, but if you squeeze the 1080 number of particles that make up the Universe into a spherical shape, using present-day physics, you get something that has a diameter of 7 X 1012 meters (the calculation is given in my book, ‘Return of the Ether,’ ). A very big grapefruit indeed!”
Finally, the physics department claims that their grapefruit expanded by a process known as "inflation." Here there is plenty of self-criticism insisting that "inflation" is nonsense. Physicist Joao Magueijo replaces inflation with a "varying speed of light" theory  that, to me at least, is infinitely more reasonable than inflation. Again, no proof thus far but, as they say, "Stay tuned."
 Houghton Mifflin.