NewSpace 2010: Polywell and Vasimr

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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kunkmiester
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Post by kunkmiester »

In MegaTokyo 2040 they looked at using the potential difference for power generation. Think about it--you're basically bridging a giant capacitor. :shock: Why not tap it for power?
Evil is evil, no matter how small

icarus
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Post by icarus »

Yeah, why not strap a solid booster to the roof of your beat-up ford taurus and head off into the desert ....

whatta you gonna use for brakes?

GIThruster
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Post by GIThruster »

Honestly, there are just so many problems with the elevator that I can never understand how anyone could think it's a good idea.

What do you do when there's a 25 mph breeze against say, 2 miles of elevator?

I saw someone do the calc a few years ago and it's just lunacy. I swear, it has to be that people are looking for a lifetime employment project that doesn't have to generate results and can say will succeed in 50 years, then bump the number back every 10 years. Kinda like fusion and DOE. . .
"Courage is not just a virtue, but the form of every virtue at the testing point." C. S. Lewis

Skipjack
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Post by Skipjack »

Thanks for the update Paul!
I am sorry to hear the Dr. W. still requires chemo therapy.
I hope he will get better soon.
Personally I cant wait for the results of your next experiments. Even if I am very sceptical towards their success (please forgive me for that), I do see the potential if this were to work out. It would truly be a revolution.

BenTC
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Post by BenTC »

Tom Ligon wrote:opportunity to discover new modes of disaster
Love that phrase. It would make a great teaser for a job advertisment.
In theory there is no difference between theory and practice, but in practice there is.

BenTC
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Post by BenTC »

icarus wrote:Yeah, why not strap a solid booster to the roof of your beat-up ford taurus and head off into the desert ....

whatta you gonna use for brakes?
Reminded me of that Darwin Award. Just checked, and I'm disappointed to discover its not true.
http://www.darwinawards.com/darwin/darwin1995-04.html
In theory there is no difference between theory and practice, but in practice there is.

WizWom
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Post by WizWom »

GIThruster wrote:
WizWom wrote: With all due respect, Dr. March, while i appreciate the attempt to model the origin of mass by Mach, I find that his explanation adds complexity without adding clarity.
I'm surprised to hear this. Can I ask, where do you think inertia comes from?
I believe it is the tendency of the waveform to not get disrupted. That is, the waveform is stable, and it requires force to change its stability.
Since gravitic and inertial effects seem identical at times,
WTF? Gravity is a force; inertia is a measure of the amount of resistance to force. Gravity acts at a distance, inertia has no effect outside of each mass. I think you are getting confused since both seem to scale with mass.
Wandering Kernel of Happiness

WizWom
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Post by WizWom »

GIThruster wrote:Honestly, there are just so many problems with the elevator that I can neWhat do you do when there's a 25 mph breeze against say, 2 miles of elevator?
Ah, now, that's calculable. Let's say a big cable, 3 cm in diameter. Cross section along 3 km is then .03*3000 = ~100 m^2; wind pressure from a 13 m/s breeze would be 120 N/m^2 or 12,000 N - trivial (about a 3/8" bolt could hold it). And that's assuming it's a square, and the wind is perpendicular.

Even if you take 100 km, you're just upping it to a 30 times that, 360,00 N.

No, it's the gale-force winds that would be the problem, and the jet stream.

But, since you'd want to use the highest mountain on the equator in a stable zone, you'll be above a good portion of the air, lessening the wind pressure significantly.

The mass of the cord itself is much more important than the shear forces from wind. By about 3 orders of magnitude. You're talking about a cord that could be wrapped around the Earth.
Wandering Kernel of Happiness

kurt9
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Post by kurt9 »

BenTC wrote:
icarus wrote:Yeah, why not strap a solid booster to the roof of your beat-up ford taurus and head off into the desert ....

whatta you gonna use for brakes?
Reminded me of that Darwin Award. Just checked, and I'm disappointed to discover its not true.
http://www.darwinawards.com/darwin/darwin1995-04.html
That was my favorite Darwin award story. I was also disappointed, but not surprised, to hear that its not true.

GIThruster
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Post by GIThruster »

WizWom wrote:
GIThruster wrote:
WizWom wrote: With all due respect, Dr. March, while i appreciate the attempt to model the origin of mass by Mach, I find that his explanation adds complexity without adding clarity.
I'm surprised to hear this. Can I ask, where do you think inertia comes from?
I believe it is the tendency of the waveform to not get disrupted. That is, the waveform is stable, and it requires force to change its stability.
Since gravitic and inertial effects seem identical at times,
WTF? Gravity is a force; inertia is a measure of the amount of resistance to force. Gravity acts at a distance, inertia has no effect outside of each mass. I think you are getting confused since both seem to scale with mass.
I suggest you read a little about Mach:

http://www.amazon.com/Machs-Principle-N ... 214&sr=8-1
Last edited by GIThruster on Wed Jul 28, 2010 5:22 pm, edited 1 time in total.
"Courage is not just a virtue, but the form of every virtue at the testing point." C. S. Lewis

kurt9
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Post by kurt9 »

GIThruster wrote:Honestly, there are just so many problems with the elevator that I can never understand how anyone could think it's a good idea.

What do you do when there's a 25 mph breeze against say, 2 miles of elevator?

I saw someone do the calc a few years ago and it's just lunacy. I swear, it has to be that people are looking for a lifetime employment project that doesn't have to generate results and can say will succeed in 50 years, then bump the number back every 10 years. Kinda like fusion and DOE. . .
I heard another problem is that of resonance along a 30,000 km cable. Also, do realize that the fullerine materials have yet to be made at the required tensile strength to make the whole thing possible. Around 60GigaPascal of tensile strength materials are necessary for the space elevator. Progress on making long length fullerine cables seems to have stalled at around 20 GPa.

Betruger
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Post by Betruger »

I don't think you can bet on such a skeptic paying a hundred bucks to supposedly read something that defies everything he knows. There's lots of free resources e.g. all the papers and powerpoints and articles for free on the net, that e.g. Paul March has linked to.

e.g.
STAIF-2007 MLT Powered Spacecraft
From this page with more resources to choose from.
Last edited by Betruger on Wed Jul 28, 2010 4:21 pm, edited 1 time in total.

GIThruster
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Post by GIThruster »

WizWom wrote:
GIThruster wrote:Honestly, there are just so many problems with the elevator that I can neWhat do you do when there's a 25 mph breeze against say, 2 miles of elevator?
Ah, now, that's calculable. Let's say a big cable, 3 cm in diameter. Cross section along 3 km is then .03*3000 = ~100 m^2; wind pressure from a 13 m/s breeze would be 120 N/m^2 or 12,000 N - trivial (about a 3/8" bolt could hold it). And that's assuming it's a square, and the wind is perpendicular.

Even if you take 100 km, you're just upping it to a 30 times that, 360,00 N.

No, it's the gale-force winds that would be the problem, and the jet stream.

But, since you'd want to use the highest mountain on the equator in a stable zone, you'll be above a good portion of the air, lessening the wind pressure significantly.

The mass of the cord itself is much more important than the shear forces from wind. By about 3 orders of magnitude. You're talking about a cord that could be wrapped around the Earth.
I think the NIAC version used tape rather than cord; it was much larger than 3cm and anchored on a platform in the Pacific. Remember also that it's tapered so it's much thicker above than below. Despite the attempts to solutions, they never had real answers for lighting storms, the wind sheer is very significant, the results of meteorite or orbital debris impact are devastating, the proposed materials react to atomic oxygen, and at each iteration, the requirements for the material strength and the length of the elevator grows.

If that's not enough, the simple fact is, the entire project requires fantastical amounts of money no one has, to build a transport system no one needs, all hoping it will bring costs down, with no real reason to suppose it will not become a great fishing-line tangle in the sky. No one spends money like this unless it's someone else's money.

If we want to see space transport become common, as in a "golden age", then it has to be orders magnitude more practical than the space elevator. This entire notion is utterly disconnected as to what is safe, quick, convenient and economical.
"Courage is not just a virtue, but the form of every virtue at the testing point." C. S. Lewis

GIThruster
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Post by GIThruster »

Betruger wrote:I don't think you can bet on such a skeptic paying a hundred bucks to supposedly read something that defies everything he knows. There's lots of free resources e.g. all the papers and powerpoints and articles for free on the net, that e.g. Paul March has linked to.
That's true but there's always the library and IMHO, as an advocate for Woodward's work, I often find it's more effective to point people to sources that have nothing to do with his work. Fact is, Woodward just brought Einstein and Mach together in ways no one had thought of in a century, but there have been significant numbers of physicists over the decades who saw the import, if not the utility of Mach's work, especially including Einstein. Indeed, one of the arguments made in the book is that Einstein owes so much to Mach that without Mach's work, we would probably not have GR.

BTW, it's never the case that Mach is defying what we know. Wiz's complaint is a common one. He didn't say that Mach's Principle (MP) was wrong, but rather that it is unnecessary, and this is in fact how the general physics establishment has felt for about 100 years. Once you have such an elegant theory as GR, you find MP much less useful--unless you're trying to explain the origin of inertia, and find a way to generate propellantless propulsion. After all, you don't have to ask where inertia comes from. You can just say it's an intrinsic property of matter (though there are an awful lot of arguments against.)

BTW Wiz, I'm not the one confused about the obvious connection between gravity and inertia. How do we simulate gravity? We spin. We generate inertia and the results are the same as a gravity field, mass suddenly has weight. That's because gravity and inertia are different outcomes of the same thing: gravinertial force (which is what makes possible the Gravinertial or "GI" Thruster.)

"I believe it is the tendency of the waveform to not get disrupted. That is, the waveform is stable, and it requires force to change its stability."

IIUC, there is still no evidence that gravity propagates as either a wave or a particle. Our only working theory of gravity is a pure field theory, and IMHO, it is best to describe what we see in those terms.
Last edited by GIThruster on Wed Jul 28, 2010 4:47 pm, edited 1 time in total.
"Courage is not just a virtue, but the form of every virtue at the testing point." C. S. Lewis

Betruger
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Post by Betruger »

Still, I don't think such a skeptic will shell out a hundred bucks for that. And there's already enough material in the freely available resources to pique anyone's interest. Anyone who's earnest about getting the straight dope without any bias. To pique their interest or give them material to precisely refute the conjecture.

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