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What is gravity ?

Posted by: Rolf Guthmann - Fri Dec 02, 2005 7:57 pm
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What is gravity ? 
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Post Simplification   Posted on: Tue Dec 06, 2005 2:32 am
Rolf:
The machine seems pretty simple, to me. According to the theory (as I understand it) there is a imperfection in Newton's 3 laws. In other words, the world works according to the laws, but not exactly. Therefore, amplify any difference with a gyroscope, and presto! movement! One question: Does the law of the maintaining of energy in all forms hold true still? Does the object just shrink/expand relatively, or what?

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Post    Posted on: Tue Dec 06, 2005 7:45 am
I remember seeing some sort of similar device in a 70's "How it works" magazine. That device had 2 gyros mounted on either end of a horizontal rod that was hinged in the middle where it attached to a vertical axle turned by an electric motor. As the rod and gyros rotated, each side was alternately forced down by a track or guide, then allowed to precess up again.

Supposedly precession is innertialess, so you get a thrust in reaction to the forced downward movement, but no thrust in reaction to the return of your 'reaction mass'. The article claimed that the measured weight of the apparatus decreased while in operation. :o

My rotational physics is too rusty to figure out whether this can work or not. :?


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Post    Posted on: Tue Dec 06, 2005 2:05 pm
This all sounds so much like the UFO counter rotating magnets drives so many wackos have promulgated. Or countless perpetual motion machines I have read about. I want to know who else has looked at this theory and what they think of it. Feynman didn't post his theories on a board for a bunch of amateurs to look at, he took it up with his professor and together they worked out the details . Who has Rolf taken it up with and what have they done with it?


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Post    Posted on: Tue Dec 06, 2005 7:48 pm
That's exactly what I've been asking for, Peter -- and I have yet to get a response.

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Post    Posted on: Wed Dec 07, 2005 2:07 am
Here's another old one, this one seems almost reasonable. they even claim to have built a working model!

http://depalma.pair.com/GenerationOfUnidirectionalForce.html

I wonder if anyone has ever tried to build one as a satelite thruster for orbit correction. If it worked it would be low thrust, but infinite ISP.

Surely someone on this forum must be able to explain why this doesn't work?

Or else why has this idea lied dormant for 30 years. Oh no, conspiracy theory? :lol:


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Post    Posted on: Wed Dec 07, 2005 8:03 am
WannabeSpaceCadet wrote:
Surely someone on this forum must be able to explain why this doesn't work?

Please be joking?!


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Post    Posted on: Wed Dec 07, 2005 2:22 pm
Burt Rutan plays with these perpetual motion machines too.
http://freeenergynews.com/Directory/Gra ... index.html
But you notice where he expends his real effort.
http://www.scaled.com/projects/tierone/index.htm


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Post    Posted on: Wed Dec 07, 2005 3:10 pm
nihiladrem wrote:
WannabeSpaceCadet wrote:
Surely someone on this forum must be able to explain why this doesn't work?

Please be joking?!


Yes, I have heard of 'Conservation of Momentum' and friction effects leading to supposedly successful tests of these devices. :wink:

But it's fascinating how variations on the same ideas keep appearing, over such a long period of time. And how no-one seems willing to refute these theories in detail.


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Post    Posted on: Wed Dec 07, 2005 4:07 pm
WannabeSpaceCadet wrote:
no-one seems willing to refute these theories in detail.
Some people do. For example:
http://www.csicop.org/si/

But it really isn't worth the trouble in most cases because some people just believe things that are not true and no amount of logic will ever change their minds. And a lot of these theories are very elaborate and you get stuck arguing about pointless tiny details far from the main point if you try to refute them in detail.

For example, can you show the error in this proof that 1=2?
let a = b
Multiply both sides by a
a^2 = ab
Add (a^2 - 2ab) to both sides
a^2 + a^2 - 2ab = ab + a^2 - 2ab
Factor the left, and collect like terms on the right
2(a^2 - ab) = a^2 - ab
Divide both sides by (a^2 - ab)
2 = 1
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It isn't actually that hard to find the error in this one, (a^2 - ab) is 0 and you can't divide by 0, but just look at how futile it was for me to try to prove that objects cannot spiral into the sun due only to the influence of the sun's gravity. After countless pages of posts showing that to be impossible, all the people who initially believed that it was possible still do.


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Post    Posted on: Wed Dec 07, 2005 5:01 pm
Are you counting me, Peter? I'm pretty sure you convinced me somewhere along the way... At least, I'm fairly convinced now.

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Post    Posted on: Wed Dec 07, 2005 5:21 pm
Oh! I though you always believed it was not possible, even before that thread. If not, the thread as not a total loss after all. :)


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Post    Posted on: Wed Dec 07, 2005 10:05 pm
yes, it seems like most of those experiments with perpetual motion or unidirectional thrust are really just complicated apparati designed so that you make a mistake somewhere and get the answer you want. A straightforward experiment could be used to prove them wrong.

For instance, all this garbage about lifters being independent of ion wind and producing uni-directional thrust could be settled once and for all if someone bothered to put one in sealed, lightweight box on a sensitive scale. Or heck, for that matter if they completely insulated all the metal parts. According to their theory, that would improve preformance anyway, b/c it would reduce ion wind "leakage" which "hurts preformance." But they never do. See especially Naudin's site for the really bunk experiments.


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Post    Posted on: Thu Dec 08, 2005 3:22 pm
And the acid test for a gyroscopic unidirectional thruster, would be a pendulum test. Surely very easy to setup.

campbelp2002 wrote:
... but just look at how futile it was for me to try to prove that objects cannot spiral into the sun due only to the influence of the sun's gravity...


You have more patience than me, I gave up on them fairly quickly.
( Although I can tell you how that can happen, over time :lol: )


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Post    Posted on: Thu Dec 08, 2005 11:10 pm
campbelp2002 wrote:
Oh! I though you always believed it was not possible, even before that thread. If not, the thread as not a total loss after all. :)


Honestly, I hadn't bothered to really think about it before that thread -- and I tend to be rather easily distracted by sexy ideas (a habit I'm hoping to fiinish training myself out of fairly soon).

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Post    Posted on: Fri Dec 09, 2005 2:11 am
spacecowboy wrote:
I tend to be rather easily distracted by sexy ideas
Gee, that NEVER happens to me! :roll: :wink:


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