### Author Topic: Propellantless Field Propulsion and application  (Read 987816 times)

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1820 on: 04/03/2013 05:13 am »
There's another question regarding momentum conservation.

Imagine a distant galaxy on the edges of the visible universe. The matter in the galaxy possesses momentum which contributes to the absolute momentum of the visible universe. If space expansion between two points gets greater than the speed of light, then the galaxy finally leaves our personal universal event horizon - and with it its momentum. From our POV, the momentum of the system "universe" seems to change (i.e. part of it is seemingly lost), because space expansion becomes greater than the speed with which information can be transferred (speed of light). One moment we know the "countable" momentum is X, the next moment it becomes X-N.

"What can't be measured, does not exist" (I hope this phrasing is correct). What are the consequences for momentum conservation, going by this example? Are there any?

Cheers,
Xpl0rer

There are no consequences for momentum conservation.

Momentum conservation applies whether the parts of the system are visible to a particular observer or not.

In your example, there are two systems, one that includes the distance galaxy and one that does not.  These two systems have different momenta.  In each system, the momentum is conserved.  At the point in time where the distance galaxy passes out of the region where you could ever receive information about it again, those two systems still exist, and each still has exactly the same momentum it did before.  The only difference is that the "visible universe" from your point of view changed from one of the two systems to the other.  Each system still independently conserves its own momentum.

Conservation of momentum doesn't care a bit about visibility.  It keeps right on going independently of whether any particular observer can ever receive information from all the parts of the system, even if no observer exists that can receive information from all parts of the system.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1821 on: 04/03/2013 05:22 am »
Imagine a distant galaxy on the edges of the visible universe. The matter in the galaxy possesses momentum which contributes to the absolute momentum of the visible universe. If space expansion between two points gets greater than the speed of light, then the galaxy finally leaves our personal universal event horizon - and with it its momentum. From our POV, the momentum of the system "universe" seems to change (i.e. part of it is seemingly lost), because space expansion becomes greater than the speed with which information can be transferred (speed of light). One moment we know the "countable" momentum is X, the next moment it becomes X-N.

This is the heart of the scenario I posted a few weeks ago.  We have one universe which started expanding from one big bang.  At first, everything, all mass, was in the same light cone.  Then some of it expanded out of the light cone.  It's as if a significant part of the universe is disappearing with each successive second.

The phrase, "I sense a great disturbance in the force" comes to mind.

Also, where the heck would this boundary be?  There's a star or galaxy on one side of the boundary, which we can no longer see.  But is that boundary also expanding faster than the speed of lite?  Then we could never see the boundary.

So when these theoretical physicists say that the inertia here is caused by mass there, how can that be? There is literally no "there" there; the boundary is receding too fast.  How can that distant mass affect local inertia instantaneously?

I think you have a fundamental misunderstanding of the idea of conservation of momentum.

Conservation of momentum does not say that distant masses instantaneously affect local masses.  What it does say is that whenever two masses do affect each other through a force, the effects on one of the masses will be equal and opposite to the effects on the other mass.

As long as there are no external forces, the combined mass of the entire system will be constant.  This does not require any instantaneous action at a distance.  It doesn't require any action at a distance at all.  If two masses interact while close and then move a great distance away and stop having a force between them, mass will continue to be conserved for the whole system simply by the fact that each will continue to have the same momentum from one moment to the next as they fly away from each other.

#### Xpl0rer

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##### Re: Propellantless Field Propulsion and application
« Reply #1822 on: 04/03/2013 09:20 am »

There are no consequences for momentum conservation.

Momentum conservation applies whether the parts of the system are visible to a particular observer or not.

In your example, there are two systems, one that includes the distance galaxy and one that does not.  These two systems have different momenta.  In each system, the momentum is conserved.  At the point in time where the distance galaxy passes out of the region where you could ever receive information about it again, those two systems still exist, and each still has exactly the same momentum it did before.  The only difference is that the "visible universe" from your point of view changed from one of the two systems to the other.  Each system still independently conserves its own momentum.

Conservation of momentum doesn't care a bit about visibility.  It keeps right on going independently of whether any particular observer can ever receive information from all the parts of the system, even if no observer exists that can receive information from all parts of the system.

I agree that "visibility" should have no consequences for whether momentum is conserved or not, omniversally speaking. I just see a problem arising in the form that there could be a situation in which some distant matter of the universe and its momentum gets separated by superluminal spacial expansion and thus leaves "our" space-time domain that's defined by "our" light cone.

It should be clear that the momentum within an inertial system is constant and the vectors annihilate time averaged. However, when some distant matter leaves "our" light cone, the momentum vectors in "our" system don't add up to Zero anymore. A factual imbalance has occurred.

Over arbitrary timescales, an averaging of momentum vectors should occur (like injected hot gas molecules imparting their greater impulse onto the masses of other molecules of a closed system). I could interpret this as a "heating process" from the "seams" of our light cone.

Concerning Woodward's effect, there's something bothering me. If the effect is to be caused by the ambient gravitational field of the distant matter, and gravity moves at the speed of light, the effect should grow weaker over time. Reason being, spacial separation grows faster and faster with distance and distant matter simply escapes faster than light (and thus gravity) can travel. Decreasing amounts of detectable matter means decreasing ambient gravitational fields.

In case the spacial expansion does not matter for the effect (see above), it gets kind of ugly IMHO, since Woodward's effect were dependent on matter that could also reside outside our space-time domain. And that could be an arbitrary amount of it in arbitrary distances we could never hope to measure. If that were the case, then Woodward's effect would simply be a "practical" means of travel without a real scientific basis (because we can't experiment with and measure stuff that's "infinitely" far away).

There are too many open questions. Nevertheless, I'd be grinning like the Cheshire cat if some real, usable devices pop up from that.

Best regards
Xpl0rer

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1823 on: 04/03/2013 10:29 am »

There are no consequences for momentum conservation.

Momentum conservation applies whether the parts of the system are visible to a particular observer or not.

In your example, there are two systems, one that includes the distance galaxy and one that does not.  These two systems have different momenta.  In each system, the momentum is conserved.  At the point in time where the distance galaxy passes out of the region where you could ever receive information about it again, those two systems still exist, and each still has exactly the same momentum it did before.  The only difference is that the "visible universe" from your point of view changed from one of the two systems to the other.  Each system still independently conserves its own momentum.

Conservation of momentum doesn't care a bit about visibility.  It keeps right on going independently of whether any particular observer can ever receive information from all the parts of the system, even if no observer exists that can receive information from all parts of the system.

I agree that "visibility" should have no consequences for whether momentum is conserved or not, omniversally speaking. I just see a problem arising in the form that there could be a situation in which some distant matter of the universe and its momentum gets separated by superluminal spacial expansion and thus leaves "our" space-time domain that's defined by "our" light cone.

Again, it doesn't matter at all whether some distant matter goes out of our light cone.  It has no effect on conservation of matter for any system, nor on the momentum of any mass.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1824 on: 04/03/2013 10:38 am »

There are no consequences for momentum conservation.

Momentum conservation applies whether the parts of the system are visible to a particular observer or not.

In your example, there are two systems, one that includes the distance galaxy and one that does not.  These two systems have different momenta.  In each system, the momentum is conserved.  At the point in time where the distance galaxy passes out of the region where you could ever receive information about it again, those two systems still exist, and each still has exactly the same momentum it did before.  The only difference is that the "visible universe" from your point of view changed from one of the two systems to the other.  Each system still independently conserves its own momentum.

Conservation of momentum doesn't care a bit about visibility.  It keeps right on going independently of whether any particular observer can ever receive information from all the parts of the system, even if no observer exists that can receive information from all parts of the system.

It should be clear that the momentum within an inertial system is constant and the vectors annihilate time averaged. However, when some distant matter leaves "our" light cone, the momentum vectors in "our" system don't add up to Zero anymore. A factual imbalance has occurred.

No.  No "factual imbalance" has occurred.

As I said before, there are two systems, one without the distant mass and one with it.  Each system is conserving its own momentum over time.  You're making the mistake of defining "all the mass currently in my light cone" as a system that should have its momentum conserved.  But that is wrong.  The system of "all the mass currently in my light cone" is *not* a closed system.  Mass is being removed from it over time.  You can't expect momentum to be the same before and after you remove some of the mass from that system.

It's just as wrong as if I defined a system as "all the mass within 100 feet of my rocket", then noticed that when I fire my rocket engine, after some time the net momentum of "all the mass within 100 feet of my rocket" has changed.  Of course it changed, because some of the propellent went more than 100 feet from the back of my rocket.

All momentum conservation laws assume you're talking about the same set of masses at times T1 and T2.  You can't compare the momentum of one set of masses at time T1 with the momentum of another set of masses at time T2.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1825 on: 04/03/2013 10:54 am »

There are no consequences for momentum conservation.

Momentum conservation applies whether the parts of the system are visible to a particular observer or not.

In your example, there are two systems, one that includes the distance galaxy and one that does not.  These two systems have different momenta.  In each system, the momentum is conserved.  At the point in time where the distance galaxy passes out of the region where you could ever receive information about it again, those two systems still exist, and each still has exactly the same momentum it did before.  The only difference is that the "visible universe" from your point of view changed from one of the two systems to the other.  Each system still independently conserves its own momentum.

Conservation of momentum doesn't care a bit about visibility.  It keeps right on going independently of whether any particular observer can ever receive information from all the parts of the system, even if no observer exists that can receive information from all parts of the system.

Concerning Woodward's effect, there's something bothering me. ...

The only thing that should be bothering you about Woodward's Effect is that it's pseudo-scientific nonsense.

Woodward published his theories more than 20 years ago, yet he has failed to convince any mainstream physicist that it has any truth to it.  Woodward doesn't even have a doctorate in physics -- his PhD is in history.

#### Xpl0rer

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##### Re: Propellantless Field Propulsion and application
« Reply #1826 on: 04/03/2013 11:23 am »
By using this "100 feet away" picture, I think you ignore a relevant qualitative difference. In your example, the ejected propellant is still within a volume that is connected to the rocket via light speed (i.e. rocket and propellant are within a causally connected volume) - even if the propellant is outside your arbitrary set system limits.

I think that what you don't quite realize is that a superluminal spacial expanison between very distant objects irrecoverably cuts off the causal connectivity between those objects. This is not trivial and can't be ignored by simply saying "the vanished matter still retains its impulse". It is scientifically impossible to state what happens or not outside our light cone. Our causal reality is defined by the things we can interact with. And that's exactly the stuff that's connected by causality (i.e. light speed).

I agree that, purely logically, the momentum of the vanished matter should be the same in itself even after the vanishing outside our light cone. But I see a problem here, too. Momentum is a vector, which is coordinate system dependent. But if the matter leaves "our" coordinate system via spacial expansion, are those systems still equivalent? Can this be falsified in any way? I doubt it.

I just want to say with all of that that reality isn't that simple, even if some would like to have it that way. I don't know if Woodward's math or explanations have anything to do with how reality works. Math is IMO just a tool that (sometimes) allows for good enough approximations of what reality does. Until the models need improvement. I personally find the idea of waves traveling back in time from distant matter to justify the Mach effect hair-raising, to say the least. But hey, what do I know.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1827 on: 04/03/2013 11:32 am »
Hello,

there's a thought experiment concerning propulsion I'd like to present. Imagine two objects with different mass in free space, being apart 1ly. They are connected by an ideal rope of negligible mass. As is known, space is expanding at a rate of about (21.25km/s)/Mly or (2.125cm/s)/ly. Since the amount of space between the objects is increasing and the rope prevents the objects from moving apart, they experience a net diametral force, each pulling on the other object.

Is my assumption correct, that the object with more mass pulls stronger on the object with less mass (since both objects are being moved with their local space-time section) and thus the less mass-rich object moves away from a nearby free observer? Wouldn't this also be a propellantless propulsion, or am I missing something?

Best regards

Yes, you're missing something.  The smaller mass would experience more of a displacement relative to the inertial frame it was initially at rest in than the larger mass, but each mass would move toward the other, and the center of mass of the two-mass system would remain at rest in the inertial frame in which it was initially at rest.

Here's an analogy (an imperfect analogy, but one that might give some intuitive feel for what is going on):  Imagine a flat merry-go round.  Place several rocks on one side and several others on the other side.  Tie one of the rocks from one side to another rock on the other side with a different mass.  Now spin up the merry-go-round.  Assume the surface of the merry-go-round doesn't have much friction, so the rocks are free to slide around it, but watch with a camera that rotates with the merry-go-round from a point directly above the center of it.  What do you see in this camera?  Well, you see the group of rocks that aren't on the rope fly off away from the center of the merry-go-round.  Relative to the group of rocks around the small rock, that rock seems to move inward, because the rocks around it are flying out.  The same is true of the larger rock on the other end, relative to the rocks around it that fly off in the other direction.  But for the rocks on the rope to stay stationary in the view of the camera, the center of the merry-go-round must be closer to the larger mass.  So the rocks around the smaller mass will fly off faster than those around the larger mass.  That is, the small mass will seem to be accelerating faster relative to the rocks around it than the large mass seems to be accelerating relative to the rocks around the large mass.  And yet, the center of mass of the two rock system will remain exactly where it as.

So, there's no propellantless propulsion going on.  The center of mass of the two-mass system experiences no movement at all, even though the smaller mass seems to see a larger acceleration than the larger mass.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1828 on: 04/03/2013 11:59 am »
By using this "100 feet away" picture, I think you ignore a relevant qualitative difference. In your example, the ejected propellant is still within a volume that is connected to the rocket via light speed (i.e. rocket and propellant are within a causally connected volume) - even if the propellant is outside your arbitrary set system limits.

No, I'm not ignoring a relevant qualitative difference.  There is no relevant difference.  That is my point.

You may care about whether a mass is in your light cone or not, but conservation of momentum does not.

I think that what you don't quite realize is that a superluminal spacial expanison between very distant objects irrecoverably cuts off the causal connectivity between those objects.

Of course I realize that.  That's what I've meant when I've talked about a light cone, just as you have.

But causal connectivity has nothing to do with conservation of momentum.  Momentum continues to be conserved in a system even if two parts of that system can no longer have any effect on one another.

You seem to think conservation of momentum is some kind of ongoing effect one mass is having on another.  It is not.

This is not trivial and can't be ignored by simply saying "the vanished matter still retains its impulse". It is scientifically impossible to state what happens or not outside our light cone.

It doesn't matter whether we know what happens to the mass outside our light cone.  Either something else exerts a force on the distant mass, in which case the system is no longer closed and there is no conservation of momentum, or nothing else exerts a force on the distant mass, and the two mass system conserves its momentum.  We don't have to know what actually happens to know that whatever it is, the total system momentum is only changed if an outside force is applied.  And, in any case, something exerting a force on the distant mass affects the momentum of the distant mass and the momentum of the two-mass system, but it doesn't affect the momentum of the local mass.

Our causal reality is defined by the things we can interact with. And that's exactly the stuff that's connected by causality (i.e. light speed).

I agree that, purely logically, the momentum of the vanished matter should be the same in itself even after the vanishing outside our light cone. But I see a problem here, too. Momentum is a vector, which is coordinate system dependent. But if the matter leaves "our" coordinate system via spacial expansion, are those systems still equivalent? Can this be falsified in any way? I doubt it.

It doesn't leave our coordinate system.  It only leaves our light cone.  It's still in our coordinate system.

I just want to say with all of that that reality isn't that simple, even if some would like to have it that way.

When you say "reality isn't that simple" do you mean what I am claiming is false?  Because everything I've been claiming is pretty basic physics.  Ask any one of tens of thousands of professional physicists and they would agree with what I said.

I don't know if Woodward's math or explanations have anything to do with how reality works. Math is IMO just a tool that (sometimes) allows for good enough approximations of what reality does. Until the models need improvement.

And professional physicists are working every day to explore the limits of our current models and come up with better models.  But they do it based on a good understanding of the current models, and careful, peer-reviewed experimental results.

Woodward's explanations, unfortunately, show a profound misunderstanding of current models of physics, and his experimental methods have not been convincing to any mainstream physicists.

I personally find the idea of waves traveling back in time from distant matter to justify the Mach effect hair-raising, to say the least. But hey, what do I know.

Sadly, as nice as it would be for Woodward's theories to be true, all logic and evidence currently available argues that they are not.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1829 on: 04/03/2013 12:08 pm »
Also, where the heck would this boundary be?  There's a star or galaxy on one side of the boundary, which we can no longer see.  But is that boundary also expanding faster than the speed of lite?  Then we could never see the boundary.

It's not the sort of boundary you would ever directly see, any more than you can see the event horizon of a black hole.

So when these theoretical physicists say that the inertia here is caused by mass there, how can that be? There is literally no "there" there; the boundary is receding too fast.  How can that distant mass affect local inertia instantaneously?

No reputable theoretical physicist would ever say that inertia here is caused by mass there.

#### ChrisWilson68

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##### Re: Propellantless Field Propulsion and application
« Reply #1830 on: 04/03/2013 12:15 pm »
Thanks, QuantumG :) .

I'd like to expand on that thought experiment and change it slightly. Imagine the two objects being identical viewing platforms. Two astronauts of equal mass are placed on them, their heads facing towards each other. Since there is a constant spacial displacement going on, the astronauts are being "pushed" against their respective viewing platforms. I think this should have the same effect as gravity would have for them, as long as they are standing on the platforms which are connected via the aforementioned rope. What do you think?

You are correct.  Each astronaut would experience a gravity-like acceleration pulling him or her into the viewing platform.

#### JohnFornaro

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##### Re: Propellantless Field Propulsion and application
« Reply #1831 on: 04/03/2013 02:23 pm »
There are no consequences for momentum conservation.

Momentum conservation applies whether the parts of the system are visible to a particular observer or not.

... At the point in time where the distant galaxy passes out of the region where you could ever receive information about it again, those two systems still exist, and each still has exactly the same momentum it did before.  The only difference is that the "visible universe" from your point of view changed from one of the two systems to the other.  Each system still independently conserves its own momentum.

Conservation of momentum doesn't care a bit about visibility.  It keeps right on going independently of whether any particular observer can ever receive information from all the parts of the system, even if no observer exists that can receive information from all parts of the system.

This is not making sufficient sense to me.  If, "momentum conservation applies whether the parts of the system are visible to a particular observer or not", then there must be instantaneous action at a distance over that fast moving boundary, and it must hold for the entire universe.

Perhaps it is thought that momentum is not information, therefore not required to follow the speed limit, c?  That's what "visibilty" presumes.

I think you have a fundamental misunderstanding of the idea of conservation of momentum.

Conservation of momentum does not say that distant masses instantaneously affect local masses.  What it does say is that whenever two masses do affect each other through a force, the effects on one of the masses will be equal and opposite to the effects on the other mass.

As long as there are no external forces, the combined mass of the entire system will be constant.  This does not require any instantaneous action at a distance.  It doesn't require any action at a distance at all.  If two masses interact while close and then move a great distance away and stop having a force between them, mass will continue to be conserved for the whole system simply by the fact that each will continue to have the same momentum from one moment to the next as they fly away from each other.

As long as they are in the same light cone, apparently.

I have a pretty good understanding of the idea of conservation of momentum.

I do not understand the ramifications of the  "boundary" conditions being discussed, nor the effect that the speed of the moving boundary has upon distant objects.  Plus, in Woodward's scheme, there are external forces; the energy required to start his machine working.

Explorer sez it beter than I do:

It should be clear that the momentum within an inertial system is constant and the vectors annihilate time averaged. However, when some distant matter leaves "our" light cone, the momentum vectors in "our" system don't add up to Zero anymore. A factual imbalance has occurred.

And you seem to be saying the same thing:

The system of "all the mass currently in my light cone" is *not* a closed system.  Mass is being removed from it over time.  You can't expect momentum to be the same before and after you remove some of the mass from that system.

He doesn't expect the momentum to remain the same.  Neither do you.  What is your point of difference?
Sometimes I just flat out don't get it.

#### JohnFornaro

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##### Re: Propellantless Field Propulsion and application
« Reply #1832 on: 04/03/2013 02:37 pm »
Here's an analogy (an imperfect analogy, but one that might give some intuitive feel for what is going on):  Imagine a flat merry-go round.  Place several rocks on one side and several others on the other side.  Tie one of the rocks from one side to another rock on the other side with a different mass.

Rolling with this analogy.  There's a limit, say c,  to the length of string tying the rocks together.  This is the light cone of causality.  When the string breaks, what happens?

But causal connectivity has nothing to do with conservation of momentum.  Momentum continues to be conserved in a system even if two parts of that system can no longer have any effect on one another.

If that is true, then continuing with the analogy, even if the string is broken, the rocks behave in the same way, only now, distant mass out "there" affects local inertia "here".

It doesn't leave our coordinate system.  It only leaves our light cone.  It's still in our coordinate system.

Beyond our light cone, we cannot know any information about any other coordinate system.

Quote from: ChrisWilson
It doesn't leave our coordinate system.  It only leaves our light cone.  It's still in our coordinate system.

That may be true, but he has not yet been totally repudiated by mainstream physics.  The mainstream physicists are engaging in prior contempt of his ideas and math.  Therefore, they take the lazy way out, and will not do the math, like that lazy fella above who will not discuss Sciama 1953, which is the basis of Woodward's definition of inertia.

You are free to insist that "No reputable theoretical physicist would ever say that inertia here is caused by mass there."  I don't know about that; I insist first that Mach and Sciama be either confirmed or repudiated.  Then Woodward can be subject to further analysis.
Sometimes I just flat out don't get it.

#### Xpl0rer

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##### Re: Propellantless Field Propulsion and application
« Reply #1833 on: 04/03/2013 05:12 pm »
@ JohnFornaro

I don't think I understand what you mean. Why should something happening "an eternity away" affect any local momentum? It sounds more like magic than physics to me .

Anyway, your last quote from ChrisWilson68 IMHO correctly pointed out a contradiction. Does momentum change, or doesn't it? It seems to me that the spacial expansion defines a one-way door. So it is neither an open nor a closed system. It's more like a half-open or half-closed system. Hence I think using the terms "open/closed system" isn't adequate in this context.

#### JohnFornaro

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##### Re: Propellantless Field Propulsion and application
« Reply #1834 on: 04/03/2013 05:33 pm »
@ JohnFornaro

I don't think I understand what you mean. Why should something happening "an eternity away" affect any local momentum? It sounds more like magic than physics to me.

Probably the reason you don't understand the question that I asked is because you have not summarized or rephrased my question correctly.

I didn't use the term "eternity away", nor did I insist that there "should" be an effect.
Sometimes I just flat out don't get it.

#### Xpl0rer

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##### Re: Propellantless Field Propulsion and application
« Reply #1835 on: 04/03/2013 05:55 pm »
Ah, my bad. I did not intend to rephrase or anything.

#### cordwainer

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##### Re: Propellantless Field Propulsion and application
« Reply #1836 on: 04/07/2013 12:00 am »
EmDrive is bunk but Quantum Vacuum Plasma Thrusters might not be pseudoscience although I suspect that it would be better to call them Quantum Vacuum Plasma Tethers since they would operate on "open systems" like electrodynamic tethers. Theoretically an electrodynamic tether or mag-sail could break away from the Earth's gravity well, via Magbeam propulsion or some form of "giganto-magnetism". Though large diamagnetic repulsive forces have been demonstrated they normally require rare and expensive diamagnetic materials.

#### cordwainer

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##### Re: Propellantless Field Propulsion and application
« Reply #1837 on: 04/08/2013 07:33 pm »
I do wonder if you could make a electrodynamic tether out of plasma similar to a mini-magnetospheric sail. I know ion propulsion systems use the Earth's electromagnetic field to impart inertia to their propellant stream at times while in flight. If you could only bounce plasma between two ships through field reversal or magnetic mirrors, you might be able to improve upon the electrodynamic effect that magnetic fields have on your "tether" through the giganto-magnetic effect sometimes exhibited in highly charged plasmas. Of course you would have to use a lot of fuel  or physical tethers to keep your two ships from pushing away from one another. Being able to adjust the charge and flow rate of the plasma might make the tether more efficient as well.

#### Anatol

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##### Re: Propellantless Field Propulsion and application
« Reply #1838 on: 11/10/2013 03:04 pm »
In the past  decade  in  the USA  competitions of  space elevator prototypes were carried out.  The climbers were fitted with  photovoltaic array facing  towards  the Earth and scaled the tether using a ground-based high power laser. The success of the specified space launch method raises doubts. The innovative system will arise if  the subsidiary tether of a heat-sensitive shape memory  material is fastened to  the main space elevator cable.
« Last Edit: 11/12/2013 09:19 am by Anatol »

#### JohnFornaro

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##### Re: Propellantless Field Propulsion and application
« Reply #1839 on: 09/23/2014 01:05 am »