Recent content by skeptic
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How do ionic wind Lifters really work?
There was an academic paper about lifters in a recent issue of the Journal of Electrostatics. No mystery, but I was a little surprised at some of the references. Academics should ignore 'internet crackpots'.- skeptic
- Post #14
- Forum: General Discussion
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Is a Space Drive Without Explosions Possible?
The 'ISBP OS Project' looks like pure nonsense to me. Lockheed have patented a similar, but simpler, device which is supposed to project a 'magnetic beam'. I built one, and tested it with iron filings. There was just the short-range pattern which one would expect. The beam was just some sort of...- skeptic
- Post #39
- Forum: Aerospace Engineering
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Would you please tell me if UFO is for real?
I don't believe that it ever really existed. I have spent years on trying to track down the facts behind newspaper reports, or items in 'specialist' magazines. Nobody ever seems to know what happened to the evidence. Alternatively, they claim that 'the military took it'. One would expect that...- skeptic
- Post #46
- Forum: General Discussion
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Is a Space Drive Without Explosions Possible?
"Could you be more specific and straightforward skeptic? I'm never good when it comes to understanding sarcasm. Are you saying that physicists working in the private sector are making significant contributions in this field?" I fail to see any sarcasm, and I do not see how I could have been...- skeptic
- Post #34
- Forum: Aerospace Engineering
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Would you please tell me if UFO is for real?
"I once read an analysis of a sample recovered from an apparent UFO crash site, in 1957. The sample was shown to be 100% pure magnesium. It also stated that no lab could ever produce 100% pure magnesium, because at the very best it would always be 99.9 or 99.9999%. I wonder if it is possible...- skeptic
- Post #44
- Forum: General Discussion
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Would you please tell me if UFO is for real?
Somebody mentioned 'compelling evidence'. What might that be, and who is judging? For instance, a laboratory in which I was working produced one of the very first macroscopic pieces of metallic glass. As a joke, we gave a sample to an expert electron microscopist who was working just next door...- skeptic
- Post #35
- Forum: General Discussion
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Is a Space Drive Without Explosions Possible?
Take a look at Progress in Aerospace Sciences, Jan. 2003. This is a review, of space-drive possibilities, written by a supposed 'expert' in the field. Any physicist who reads this review will be astonished by the utter stupidity of some of the ideas which high-tech companies are apparently...- skeptic
- Post #30
- Forum: Aerospace Engineering
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Axial rotation of a magnetic field detection
People have been arguing, on-and-off, about this for years. Many electrical engineers insist that the magnetic field rotates with the magnet. Physicists take the view that, since the magnetic field lines are merely a mathematical artifice, it is meaningless to talk about their rotation.- skeptic
- Post #6
- Forum: Electromagnetism
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How much does it cost to publish a book?
Most large printing companies now offer a service known as 'demand publishing'. It is a sort of glorified photocopying, but the product is indistinguishable from an ordinary book. Depending upon book length, it might cost 10 dollars/book, for a print-run as short as 10 books. One then sends...- skeptic
- Post #10
- Forum: General Discussion
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Universal Dynamics of Tumor Growth: A Breakthrough
Why is the OP surprised that mathematics can be applied to this? Mathematics can be applied to anything (but with varying degrees of success). -
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Is a Space Drive Without Explosions Possible?
Why not patent it first, and then discuss it? Contrary to popular belief, one can get anything past the patent office. Perpetual motion, anti-gravity, faster-than-light communication, objects that are bigger inside than they are outside? No problem. Just pay the fee.- skeptic
- Post #5
- Forum: Aerospace Engineering
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Gyroscope - I just don't get it.
Eric Laithwaite was one of those most dangerous creatures: a career-crackpot who managed (I blame it on a shortage of university manpower after WWII) to get himself into a position of academic power. The gyroscope affair was only the tip of the iceberg. He also fancied that he was an expert on...- skeptic
- Post #36
- Forum: Classical Physics
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The Mechanism of Falling Object: no gravity
I am not sure that it is worth replying to someone who confuses the first and second names of the author of one of the most famous popular-science books. However, what I think you are trying to say is that, if a gravitational field gradient is sufficiently intense (or if an object is of... -
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Gyroscopes as navigational devices
Although inertial navigation devices make use of the fixed orientation of a gyroscope, the more traditional method is to exploit the fact that a properly counterweighted gyroscope will tend to align itself with the Earth's axis.- skeptic
- Post #3
- Forum: Classical Physics
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How Does Physics Influence Cycling Performance?
You can certainly forget gyroscope effects with respect to bicycle stability. Dr DEH Jones ('Daedelus' of Nature magazine) showed years ago that gyroscope effects do not explain bicycle stability. It is fairly obvious really: it is easy to balance a bicycle even when the wheels are hardly...- skeptic
- Post #4
- Forum: Introductory Physics Homework Help