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Comment Re:Who is it for? (Score 1) 325

There is no equally-named Kemp on arxiv.org (there is a "R.Kemp", where "R." seems to stand for "Roger" in two solid-state chemistry/physics papers), and there are no google hits with his name and +site:.edu.

On http://www.superprincipia.com/About_The_Author.htm is the author's CV, he is essentially a radar engineer (probably a good one given the companies he worked at), and worked as a math teacher at some time. In the autumn of 1989 he suffered an attack of Holy Spirit and seems not to have recovered yet.

Unfortunately the website gives no sample chapters for download. I'd expect the book to be a stylistically pleasant reading, but I cannot tell if the hard core physics stuff is correct (and free from esoteric stuff). When in doubt, I'd stick with Penrose (his two-volume book with Rindler is great, his popular stuff as well (except when he tries to push his unorthodox interpretation of quantum mechanics)).

The wensite says the book requires "basic understanding into algebra, geometry, differential calculus, and integral calculus". Since that little math is not even sufficient to understand the currently generally accepted theories of physics (one needs at least differential geometry, algebraic topology, functional analysis and Lie groups for even the simplest things), I have some doubts whether the book really *explains* physics or just tells a story *about* physics.

The fact that he has no PhD should not matter (he seems not to want one), and even Einstein got PhD his only a year after Special Relativity.
His paper about photons is mostly prose with very few equations in between, and sounds strange (to say it mildly), which has already been mentioned by other commenters here.

Meta-question: Why is "Post anonymously" next to the checkbox written in white on white background? Buggy CSS or broken browser?

Comment Re:I see nothing snake-like here.. (Score 1) 90

The twisting on the ground looks like an attempt at sidewinding, but the videos at the linked site show that the robots can do that properly (maybe they need a good ground for that - but sidewinding *is* for flat grounds whereas undulation is OK for crawling among vegetables).
Rolling (both on the ground and as a method of climbing trees) is not that bad - it is easy for robots but hard for real snakes (whose scales are specialized for locomotory use only on the ventral side).
Btw., Gavin Miller (http://www.snakerobots.com/S3.html) made a working sidewinder back in 1996.

Comment Re:False assumption (Score 1) 814

This might work in languages where indentation is just for humans. In Python, where indentation matters, tabs are evil (you would need to *know* how wide was a tab in the machine of the guy who wrote the code in order to read or edit it). This information usually is not part of the source (unless the author inserted a file variable (i.e.
"# -*- tab-width: 7 -*-")).

Comment Re:can we try something different? (Score 2, Informative) 243

It doesn't really matter what the west thinks about communism - NK is a theocracy now, with a god-king at the top and a caste system below. They started replacing marxism with the artificial Chuche-religion (more weird than Scientology, and probably as evil) in the seventies.
The only chance for NK is IMHO a internal enlightenment in parts of the leading junta (the only people there who know that there is a different world outside, and probably don't believe in the Chuche crap they made up for the ordinary people). All the world can do is to offer the leaders a retirement without being killed; and an efficient, friendly madhouse for the deprogramming of the population.

Comment Re:Danger vs. Visibility (Score 1) 351

A purely unrealistic idea came after submitting: Instead of illuminating the whole area, illuminate a mm-sized milliwatt-powered spot every meter. Such a spot is visible on the ground even in daylight (laser pointers to exactly that). Unfortunately, the laws of optics get in the way: To get meter-resolution on the ground, we need meter-sized optics in orbit (that's what spy satellites do (to get resolutions in the decimeter range, they fly very low and crash down all the time due to aerobraking)). For mm-resolution, we'd need kilometer-sized satellites.

Comment Danger vs. Visibility (Score 1) 351

IMHO, this cannot work. Sunlight comes with approx. 1kW/m^2, the human eye detect changes in brightness if they exceed 30%, i.e. we'd need 300W/m^2 to be visible at daytime. OTOH, looking directly at the sun is harmful even with the sun having a diameter of 0.5 degrees. A light source with a third of the sun's brightness, but point-like would probably burn a hole right through the retina before the blink reflex can kick in.
Even the discussed 10W/m^2 (absolutely invisible unless one looks directly at the right point in the sky) would be dangerous (the eye's resolution is one angular minute, i.e. light from a point source would cover 1/900 of the sun's image's area, giving a retina burning power density of 9 suns).

Short wording: you can't see it unless it makes you blind.

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