41–50 of 205 posts
https://plus.google.com/117663015413546257905/posts/WfFtJ8bY...
https://plus.google.com/117663015413546257905/posts/C7vx2G85...
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No, I've a masters degree in Physics, and did several research projects on turbulent/laminar flow. We have a detailed understanding of a variety of theories which correctly represent the lift effect experienced on a body moving through a flow, yet none of them do it perfectly or completely. We can implement the technology well, but not without the aid of wind-tunnels and brute-force computer simulations in order to v…
Fluid flow is complicated, true - but the basic physical phenomenon of lift is very simple and completely understood: wings redirect air downwards, and the reaction force is what we call lift.
Where can I find blueprints?
Earlier quoted context omitted.
No, I've a masters degree in Physics, and did several research projects on turbulent/laminar flow. We have a detailed understanding of a variety of theories which correctly represent the lift effect experienced on a body moving through a flow, yet none of them do it perfectly or completely. We can implement the technology well, but not without the aid of wind-tunnels and brute-force computer simulations in order to v…
It doesn't imply a deterministic universe any more than vanilla many-worlds. Sure, the pilot wave is deterministic. But when you actually measure the position of the particle? You get one of many possible results, with probability determined by the pilot wave. Big whoop. We understand QM perfectly well in the only meaningful sense - we can predict the results of any experiment. There's plenty of arguing about "what i…
Is argue that understanding the "basement" is very much physics - sure, it can err into the philosophical, but it's still definitely a "real" physical process which drives this.
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We understand perfectly well how wings work. What is it with Hacker News and anti-intellectualism?
For various values of "we". http://www.grc.nasa.gov/WWW/K-12/airplane/lift1.html > There are many explanations for the generation of lift found in encyclopedias, in basic physics textbooks, and on Web sites. Unfortunately, many of the explanations are misleading and incorrect. Theories on the generation of lift have become a source of great controversy and a topic for heated arguments. There are lots of bits of scien…
A nice blog post on the topic is Sean Carroll's article, "The Laws Underlying The Physics of Everyday Life Are Completely Understood" (http://blogs.discovermagazine.com/cosmicvariance/2010/09/23/...).
So what's the difference between what NASA does, what Chinese did with Em drive and what Russians have orbiting in Yubileiny satellite? More interesting question: can I make one at home? I can do magnetic levitation, both pushing and pulling with high-frequency electromagnets; it would be cool if I could do this as well and having floating objects in my home 8-)
" it would be cool if I could do this as well and having floating objects in my home " The reported thrust of the device is in the tens of micronewtons. Assuming it weighs 1 kg, you would need approximately a million times more thrust for the device to levitate (i.e. counteract its own weight) at the surface of the earth.
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No, I've a masters degree in Physics, and did several research projects on turbulent/laminar flow. We have a detailed understanding of a variety of theories which correctly represent the lift effect experienced on a body moving through a flow, yet none of them do it perfectly or completely. We can implement the technology well, but not without the aid of wind-tunnels and brute-force computer simulations in order to v…
Well, if brute-force computers simulations correctly represent a wing, then we do know how they work. We may need wind-tunnel tests even if we have a perfectly realistic model, because we may not know if our simulations converge.
By contrast, this "reactionless drive" posits both a completely unknown underlying physical mechanism and a major violation of physics-as-we-know-it (i.e. action without reaction).
Here are two nice posts by physicist John Baez with some reasons to be skeptical about the "reactionless drive": https://plus.google.com/117663015413546257905/posts/WfFtJ8bY... https://plus.google.com/117663015413546257905/posts/C7vx2G85...
I think he's slipping from skepticism to cynicism here.
Please be true, please be true! How big is a two megawatt nuclear power source anyway? A quick search showed nuclear power plants are in the hundreds to low thousands of megawatt range, and RTGs are in the tens to hundreds of watt range. I have no idea what something that lies between those two would be.
One example is the small nuclear reactors that have been used in orbit already: http://en.wikipedia.org/wiki/TOPAZ_nuclear_reactor