Author Topic: Propellantless Field Propulsion and application  (Read 664971 times)

Offline JohnFornaro

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Re: Propellantless Field Propulsion and application
« Reply #240 on: 04/18/2009 01:44 PM »
"Anyone interested in doing this work is invited to do so."  Certainly, but that's also like saying, "anyone who wants to build a hydrogen fueled automobile is free to do so."  Easy to say and fairly hard to do.

Anyhow, about the gold leaf. you can levitate a ping pong ball in the air from the other end of a vacuum cleaner.  In order to propel something, there has to be a directional force somewhere.  If we're using the universe to push against that gold leaf, then so be it.

Point is, if this is going to be a rocket, something needs to be pushed.  Yeah, levitating itself around the lab would be a very impressive display, sure to get investor dollars.  But I think an easier display is to demonstrate lifting something against the pull of Earth's gravity.

Am I correct that the device doesn't have enough thrust to escape Earth's gravity?  But it has some thrust.  Maybe not levitate a gold leaf, but push against a balance beam, then.  Something that the guy with money can see.

I also don't understand why he doesn't seek funding.  Either the science hasn't yet been proved, or he's trying to get the big bucks associated with the patent.  I have argued for altruism on this site, and have been ridiculed.  I would have a hard time believing that his is an altruistic exercise.
Sometimes I just flat out don't get it.

Offline Nathan

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Re: Propellantless Field Propulsion and application
« Reply #241 on: 04/18/2009 02:36 PM »
Quote
Quote
EM-Drive is not fake science. They have a WORKING prototype and are moving towards a flight test in 2009. www.emdrive.com. This uses actual physics and obeys all the convervation laws.

I am NOT impressed by this site.  It states that just like a laser ring gyro is a closed system and can measure rotation rate, this drive is a closed system that can produce force.  Newton and all have NO problem with a closed system measuring rotation rate.  No need to introduce Special Theory effects to explain this.  Explaining away the closed system problem by using the laser ring gyro as an analogy tells me these people are incorrect.

However I do hope I am wrong and they produce a really nice rocket engine someday.  I for one will not be investing my money in this technology.

Danny Deger

P.S.  Maybe there is some change of momentum of the photons that balances the change of momentum of the rocket.  This would make the device not violate the law of the conservation of momentum.

I took me a while to understand how it works. There is a basic property of a waveguide that describes how the group velocity of a wave changes as the size of the waveguide changes. For the em-drive it is this that creates the force imbalance on the end walls of the cavity. In terms of momentum, if there are two equal masses and the total momentum p=p1-p2 then p is non zero when the velocities of the particle colliding at each end of the waveguide differ. The slope of the walls of the cavity ensure the collisions with the walls along the length result in a nonlinear force ie: the differing group velocities along the length of the sloping cavity ensure the particles don't just bounce around inside the cavity canceling each others forces totally out. One uses the law of relativistic velocity addition to see that there is forward motion when the thruster is viewed by an outside observer (thus an open system).
To illustrate:
If one fires two opposing canons within a closed box the impact of the canonballs against the walls will cancel out to result in zero motion. If either the velocity or the mass of one of the balls changes en-route to the wall then the impacts will not cancel out and there will be motion. The trick then is to deal with the lost mass or velocity. It has to have gone somewhere.
From the point of view of momentum; The em-drive looks at the change in velocity whereas the woodward drive looks at the change in mass. The both deal with the imbalance in different ways. EM-drive uses the properties of waveguides and relativity whereas woodward's drive uses machian mass fluctuations and a rectifier.
When one accounts for the energy absorbed into the system to create the motion then one retains conversation of energy. Same for momentum.

So I think I understand. Took me a while but I think I'm there. And it is basic physics! It USES newton laws. It just needed a different perspective.



« Last Edit: 04/18/2009 02:43 PM by Nathan »
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Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #242 on: 04/18/2009 04:42 PM »
"There is a basic property of a waveguide that describes how the group velocity of a wave changes as the size of the waveguide changes."

Very interesting.  Could you explain a little more for us how this change in group velocity can explain a change in momentum without violating conservation?  I think this is the sticky point people seem to disagree with Shawyer on.

Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #243 on: 04/18/2009 05:23 PM »
"Anyone interested in doing this work is invited to do so."  Certainly, but that's also like saying, "anyone who wants to build a hydrogen fueled automobile is free to do so."  Easy to say and fairly hard to do.

Anyhow, about the gold leaf. you can levitate a ping pong ball in the air from the other end of a vacuum cleaner.  In order to propel something, there has to be a directional force somewhere.  If we're using the universe to push against that gold leaf, then so be it.

Point is, if this is going to be a rocket, something needs to be pushed.  Yeah, levitating itself around the lab would be a very impressive display, sure to get investor dollars.  But I think an easier display is to demonstrate lifting something against the pull of Earth's gravity.

Am I correct that the device doesn't have enough thrust to escape Earth's gravity?  But it has some thrust.  Maybe not levitate a gold leaf, but push against a balance beam, then.  Something that the guy with money can see.

I also don't understand why he doesn't seek funding.  Either the science hasn't yet been proved, or he's trying to get the big bucks associated with the patent.  I have argued for altruism on this site, and have been ridiculed.  I would have a hard time believing that his is an altruistic exercise.

The MLT thrusters produce thrust on the order of a few uN, the older UFG design a few hundred uN.  Paul March's MLT developed much more thrust because it was run in wormhole territory but as I've mentioned, Paul was unable to provide the proper protocols and controls for us to make strong claims about what he found.  In all these instances, the thrusters produce less force than their own weight so they will not levitate.  They are measured on the ARC Lite thrust balance and if what you want is to see something move on the balance, expect that in the next few weeks when Jim resumes his thruster studies.

And yes, it is certainly Jim's integrity that moves him to refrain from looking for cash like most others in this business.  Perhaps this is the natural consequence that he's in his late 70's with a couple different types of terminal cancer so he has a great sense of his own mortality.  In any case, he knows he can't take it with him so money is not his goal.  Proving the science and leaving a lasting legacy are more to his tastes, IMHO.

For the rest of us who want to build spaceships, Jim's patience in this area can cause us some real stress.  :-)

Again, anyone who wants to be involved in this research can make their own place.  All the relevant physics and engineering is posted.  There is a team of highly skilled engineers surrounding Jim who are happy to help others.  What's required are: the skills necessary to succeed (I'm a philosopher, it would be silly for me to think I could run one of these experiments), a desire to learn and the free time.  Time is one of those things that is on a premium since Jim is the only one involved who is working essentially full time.  Anyone wants on the mailing list, that's the best place to start to learn about the work.  Just write me a couple sentences describing your background and skills and I'll forward your address to Jim.

Offline Star-Drive

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Re: Propellantless Field Propulsion and application
« Reply #244 on: 04/18/2009 06:35 PM »
Quote
Quote

EM-Drive is not fake science. They have a WORKING prototype and are moving towards a flight test in 2009. www.emdrive.com. This uses actual physics and obeys all the convervation laws.

I am NOT impressed by this site.  It states that just like a laser ring gyro is a closed system and can measure rotation rate, this drive is a closed system that can produce force.  Newton and all have NO problem with a closed system measuring rotation rate.  No need to introduce Special Theory effects to explain this.  Explaining away the closed system problem by using the laser ring gyro as an analogy tells me these people are incorrect.

However I do hope I am wrong and they produce a really nice rocket engine someday.  I for one will not be investing my money in this technology.

Danny Deger

P.S.  Maybe there is some change of momentum of the photons that balances the change of momentum of the rocket.  This would make the device not violate the law of the conservation of momentum.

I took me a while to understand how it works. There is a basic property of a waveguide that describes how the group velocity of a wave changes as the size of the waveguide changes. For the em-drive it is this that creates the force imbalance on the end walls of the cavity. In terms of momentum, if there are two equal masses and the total momentum p=p1-p2 then p is non zero when the velocities of the particle colliding at each end of the waveguide differ. The slope of the walls of the cavity ensure the collisions with the walls along the length result in a nonlinear force ie: the differing group velocities along the length of the sloping cavity ensure the particles don't just bounce around inside the cavity canceling each others forces totally out. One uses the law of relativistic velocity addition to see that there is forward motion when the thruster is viewed by an outside observer (thus an open system).

To illustrate:

If one fires two opposing canons within a closed box the impact of the canonballs against the walls will cancel out to result in zero motion. If either the velocity or the mass of one of the balls changes en-route to the wall then the impacts will not cancel out and there will be motion. The trick then is to deal with the lost mass or velocity. It has to have gone somewhere.

From the point of view of momentum; The em-drive looks at the change in velocity whereas the woodward drive looks at the change in mass. The both deal with the imbalance in different ways. EM-drive uses the properties of waveguides and relativity whereas woodward's drive uses machian mass fluctuations and a rectifier.

When one accounts for the energy absorbed into the system to create the motion then one retains conversation of energy. Same for momentum.

So I think I understand. Took me a while but I think I'm there. And it is basic physics! It USES newton laws. It just needed a different perspective.


Nathan:

A major problem with Shawyer’s waveguide explanation is that his theoretical proof does not provide an explanation for the magnitude of the reaction forces reported.  Photon rockets of any stripe with only several hundred watts of input power can't generate thrusts measured in milli-Newtons.  Instead they can only produce pico to nano-Newtons of thrust from their local power supplies, unless they are also inadvertently tapping into a higher dimensional energy manifold as do Woodward's devices with the cosmologically derived gravinertial field. 

However, Shawyer first has to replicate his posted video experiment in a hard vacuum (<1x10-6 Torr) and get the same results, thus precluding possible ion wind or cooling fan generated thrusts before we worry too much about his proposed theoretical approach.  If he does get the same reported thrust in a vacuum though, then my bet is still on Sonny White's QVF explanation being more accurate than Shawyer’s.

BTW, as noted by GI-Thruster, I need to find the time and resources to replicate my Mach-2MHz experiment and/or exercise my new MLT-2009 test article in a hard vacuum, before we can take its results to be anything more than strongly suggestive that M-E based MLTs work as advertised.  Alas, that next step for me has proven problematic so far...
« Last Edit: 04/18/2009 06:57 PM by Star-Drive »
Star-Drive

Offline mlorrey

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Re: Propellantless Field Propulsion and application
« Reply #245 on: 04/18/2009 06:54 PM »
"Anyone interested in doing this work is invited to do so."  Certainly, but that's also like saying, "anyone who wants to build a hydrogen fueled automobile is free to do so."  Easy to say and fairly hard to do.

Anyhow, about the gold leaf. you can levitate a ping pong ball in the air from the other end of a vacuum cleaner.  In order to propel something, there has to be a directional force somewhere.  If we're using the universe to push against that gold leaf, then so be it.

Point is, if this is going to be a rocket, something needs to be pushed.  Yeah, levitating itself around the lab would be a very impressive display, sure to get investor dollars.  But I think an easier display is to demonstrate lifting something against the pull of Earth's gravity.

Am I correct that the device doesn't have enough thrust to escape Earth's gravity?  But it has some thrust.  Maybe not levitate a gold leaf, but push against a balance beam, then.  Something that the guy with money can see.

I also don't understand why he doesn't seek funding.  Either the science hasn't yet been proved, or he's trying to get the big bucks associated with the patent.  I have argued for altruism on this site, and have been ridiculed.  I would have a hard time believing that his is an altruistic exercise.

Altruism with feeding the poor is nice and good. Altruism with technology that requires significant capital investments to fully exploit is a disservice to everyone. Without an ability to gain a maximum return on the investment, venture capitalists are dissuaded from investing in a new technology.
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Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #246 on: 04/18/2009 08:52 PM »
The trouble with all funding is that one is essentially locked into pursuing whatever research one commits to in order to get the funding.  One thing I've repeatedly seen over these last 3+ years is that discovery has dictated a change in direction of research on many occasions.  If Jim had taken a venture capitalist's money to pursue the MLT, he would need to be continuing that despite that he's learned the MLT does not provide adequate bulk acceleration.  Jim has learned his lessons from the MLT and returned to UFG research.  That kind of flexibility is literally "priceless".  Same is true with this last year's worth of research on the rotator.  Now we have an entire body of new evidence of M-E, of a completely different sort than what comes from a thruster.  That's a significant breakthrough.  But suppose again Jim had taken money to pursue the MLT.  Then he would not have had the freedom a year ago to change course and attack the rotator issue for an entire year.  No investor would have been happy that Jim had essentially abandoned thrust studies in order to prove out the science.  If Jim had taken money from others, he would literally not have the freedom to make these sorts of choices.

So it's not just altruism that has Jim ignoring money.  It's common sense.

Offline Nathan

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Re: Propellantless Field Propulsion and application
« Reply #247 on: 04/18/2009 11:38 PM »
"There is a basic property of a waveguide that describes how the group velocity of a wave changes as the size of the waveguide changes."

Very interesting.  Could you explain a little more for us how this change in group velocity can explain a change in momentum without violating conservation?  I think this is the sticky point people seem to disagree with Shawyer on.
I tried to in my post. Essentially the momentum gained by the system equals the momentum lost by the electromagnetic wave within the cavity.
In my example - the momentum "mysteriously" lost by one canonball (due to change in velocity in the waveguide) is converted equally into the momentum gained by the system, thus conserving momentum. Thus nothing needs to be thrown out the back of the vehicle (which is everyones sticking point).

In response to stardrives comment on the magnitude of the effect - the effect is magnified by the large number of reflections each photon experiences at the end walls. Each reflection imparts momentum (like light hitting a solar sail would). One then needs to consider the overall power of the system to obtain the magnitude reported. The system itself does limit the effect though. If the velocity of the waveguide increases in the direction of the thrust then thrust falls to zero at some limiting velocity.

If one thinks about it - we really don't understand why momentum is transfered from one body to another - we can describe it mathematically and generate equations but why does it happen at all? And how does it happen? Perhaps the em-drive is a result of this actual process. (this is arm waving of course).

(I should have pointed out that this all depends on the fact that the actual equations for the beam velocities within the cavity do not depend of the velocity of the waveguide itself. Thus the open system point of view.)
The best paper they've produced is http://www.emdrive.com/IAC-08-C4-4-7.pdf
I suggest everyone read it and work thru the equations. I have a physics degree and I cannot find a problem with the equations at all. I cannot see anything being violated and I can see a net thrust resulting.
I do agree that we need more comprehensive testing to eliminate all possibilities, including larger unseen nulling effects. They have a new thruster due to be ready for testing in August this year.


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Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #248 on: 04/19/2009 12:39 AM »
"In my example - the momentum "mysteriously" lost by one canonball (due to change in velocity in the waveguide) is converted equally into the momentum gained by the system, thus conserving momentum."

Well, as I'm not a physicist I'll leave detailed analysis alone, but I have to say, I'm anything but convinced.  You can do the math but intuition tells me this is wrong.  If you fire one cannonball right and another left, and mysteriously drop the velocity to the right, you would have to conserve by somehow finding momentum to the right.  But instead, what you get is net force to the left.  I think that's wrong.  Sounds like someone got a sign wrong somewhere. . .

Offline Nathan

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Re: Propellantless Field Propulsion and application
« Reply #249 on: 04/19/2009 03:40 AM »
"In my example - the momentum "mysteriously" lost by one canonball (due to change in velocity in the waveguide) is converted equally into the momentum gained by the system, thus conserving momentum."

Well, as I'm not a physicist I'll leave detailed analysis alone, but I have to say, I'm anything but convinced.  You can do the math but intuition tells me this is wrong.  If you fire one cannonball right and another left, and mysteriously drop the velocity to the right, you would have to conserve by somehow finding momentum to the right.  But instead, what you get is net force to the left.  I think that's wrong.  Sounds like someone got a sign wrong somewhere. . .

Yeah. That's what had me struggling all along. But that's the beauty of the waveguide. The wavelength or the photons remains the same but the group velocity differs along the axis of the tapered waveguide. (Hence our canonball changes velocity mid flight, without consequence since the velocity of the light is not dependant on the forward velocity of the waveguide. (Thus the open system)).
The actual answer is given in equation 10 of the paper , which shows where the relativistic addition of velocities makes all the difference. The graph shows the relationship clearly.


What we are looking at here is a non-linear solution to the newton force equation. The geometry of the waveguide forces the em wave to change its group velocity along the length of the tapered cavity, based on the diameter of the cavity.This generates the momentum difference in the first place due to the photon impacts at each end.

The total momentum is conserved since the motion of the cavity becomes the extra term needed for conservation.

p1=momentum imparted on plate one.
p2=momentum imarted on plate two.
p=resultant momentum.
if p1 and p2 are unequal and opposite, there will be a resultant momentum p.
p=p2-p1
or
p-p2+p1=0

Thus momentum is conserved.
That's as simple as I can make it.



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Offline Nathan

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Re: Propellantless Field Propulsion and application
« Reply #250 on: 04/19/2009 04:21 AM »
I'll try to come up with a better illustration of the concept. It seems understandable to me but I've worked thru the equations. My intuition tells me it is correct because of this. But until one clicks ones intuition will never accept it.

Gimme a couple of days.

For those uncertain as to why the forces on each end of the waveguide differ - consider a tapered pipe with water flowing thru it. the water goes faster the smaller the pipe becomes. ie, the same mass moves thru at a higher speed in the smaller pipe than the larger one. This is analagous to the group velocity of light in a waveguide.
Faster moving water impacts a wall with higher momentum than slow moving water.
One should thus easily see that the forces on each end of the waveguide are different. That part of the illustration is easy enough. The rest is hard as it involves relativity and the concept of an open system.

Let me think on it.
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Offline JohnFornaro

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Re: Propellantless Field Propulsion and application
« Reply #251 on: 04/19/2009 02:52 PM »
Seems like small thrusts are possible.  What you need on a long interstellar flight.  Pico-Newtons aren't very much.  About the power supply: it's good that it's potentially simple.  I have an old tube Mac that probably would be too heavy to levitate itself, but I bet it could climb up a cable to the Moon.

Anyhow, the power supply so far is attached to a cable, and the demonstrated force experiments are more like a balance beam, I gather.

I like the idea of research for it's own sake, and it's true that investors frown upon an inventor changing his direction without their assent.  But I still don't get it.  Is this technology at the proof of concep phase?

Now to read IAC- 08 – C4.4.7.
Sometimes I just flat out don't get it.

Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #252 on: 04/19/2009 04:15 PM »
Seems like small thrusts are possible.  What you need on a long interstellar flight.  Pico-Newtons aren't very much.  About the power supply: it's good that it's potentially simple.  I have an old tube Mac that probably would be too heavy to levitate itself, but I bet it could climb up a cable to the Moon.

Anyhow, the power supply so far is attached to a cable, and the demonstrated force experiments are more like a balance beam, I gather.

I like the idea of research for it's own sake, and it's true that investors frown upon an inventor changing his direction without their assent.  But I still don't get it.  Is this technology at the proof of concep phase?

Now to read IAC- 08 – C4.4.7.

Woodward's thruster work is at the TRL 5-6.  There have been many sorts of "proof of concept."  The issue here is that science doesn't actually ever "prove" anything.  More what it does is disprove all the alternatives.  So point in fact, there is no one single standard of evidence that qualifies as 'scientific", etc.  What we have are many people from many backgrounds who each individually think one level of evidence is convincing and another compelling, etc.  So the goal is to compile as many sorts of evidence as possible.

The rotator evidence is very compelling to me since I understand there are no other proposed effects found in anti-phase to electrostriction that can explain Jim's findings.  So far as convincing the larger scientific community is concerned, there's no way to tell how physicists will respond.  In general they don't like each other.  :-)    It's very difficult to get physicists to respond to each other.  The only ways I know for sure to do this are either a) pay them to pay attention or b) publish in a peer review journal.  Jim did the latter over a decade ago with no complaints outstanding so really I think we are just going to have to wait for the scientific community to wake up.  One way of waking them up is to do replications as broadly as possible.

The issue of "how much thrust is enough thrust?" is a serious one.  You are tracking to think that Jim is not yet producing enough thrust to power human spaceflight.  However, UFG's producing 100's of uN are useful in their own right for things like propellantless satellite station keeping.  The fact these items have an effective Isp much higher than Ion, and use no propellant, could make even these pre-prototype thrusters a marketable item.  However, the real news is that these things all scale wonderfully, not just in how much thrust they produce, but in their thrust efficiency.  For instance, in the future we can look at exotic materials.  Thrust efficiency scales to the square of the dielectric constant (k) of the material used.  Jim is using sintered BaTiO3 caps in his upcoming UFG design with a k of around 5,000.  That's a very high k material.  Single crystal BaTiO3 has a k of closer to 10,000 but rather than cost $2/cc it costs $5,000/cc.  So you can see why we're not using single crystal caps.  But who knows what the future holds?  Perhaps we can find a way to use "hot opal" phase change dielectrics with a k over 100,000.  That would give us bang!  Thrust also scales to things like the cube of frequency and operating at higher frequencies is often easier and cheaper.  The size of switching inverters scale inversely proportional to their frequency so one route to miniaturization is simply to go to higher frequencies in the future. Then there are the parametric methods for enhancing thrust and a bunch of others.

Does that give a sense of the process going on?  It's not a sprint.  It's a marathon.

And yes, the Arc Lite balance is like a balance beam except that it is set up horizontally so that it will not confuse thrust with time-averaged changes in mass.  It's a very precise, world-class instrument built by Tom Mayhood complete with vacuum chamber that pulls E-6 Torr.   The ARC Lite is a large improvement over other thrust balances of its kind to be found in academia and at the Austrian Research Center because it has been enhanced with liquid metal power system contacts that generate no discernable resistance to rotation on the balance arm.  The ARC Lite is probably the best instrument of its kind in the world today.  I expect Jim will be publishing photos of the ARC Lite with a UFG on the arm in his weekly updates of UFG research starting in the next couple weeks.  If so I'll try to post a pic here.

Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #253 on: 04/19/2009 05:45 PM »
I'll try to come up with a better illustration of the concept. It seems understandable to me but I've worked thru the equations. My intuition tells me it is correct because of this. But until one clicks ones intuition will never accept it.

Gimme a couple of days.

For those uncertain as to why the forces on each end of the waveguide differ - consider a tapered pipe with water flowing thru it. the water goes faster the smaller the pipe becomes. ie, the same mass moves thru at a higher speed in the smaller pipe than the larger one. This is analagous to the group velocity of light in a waveguide.
Faster moving water impacts a wall with higher momentum than slow moving water.
One should thus easily see that the forces on each end of the waveguide are different. That part of the illustration is easy enough. The rest is hard as it involves relativity and the concept of an open system.

Let me think on it.

My quick survey of "group velocity" seems to say that this is the wrong way to consider momentum.  It seems to me to be more a bookkeeping invention.  When Shawyer's waveguide opens at one end, the group velocity will be lower, but the distribution of mass across that end of the waveguide will be higher because there's a larger surface area.  So in total, even though it is in some sense true to say the wave has lower velocity, it has the same momentum.  That is the bookkeeping I don't think Shawyer has done properly.

Note that group velocities can be zero and even negative but the photons always propagate at c:

http://en.wikipedia.org/wiki/Group_velocity

Offline Patchouli

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Re: Propellantless Field Propulsion and application
« Reply #254 on: 04/19/2009 05:46 PM »

It would be interesting if the device actually works but it also appears to be a relativity low thrust device like an ion rocket.
Even if it does work you'll still need a conventional rocket or RLV to get a vehicle equipped with it into orbit.

Patchouli:

You didn't read or at least understand my scaling slide that I appended earlier.  Let me summarize it here again for you.  There are no currently known theoretical limits on the thrust generation capability of a gravinertial (G/I) field drive.  The only limits on the maximum thrust production for a given device are related to the design implementation details of the G/I thruster in question, i.e., how much power it can handle before it burns out and/or flys apart, just like you can build small rockets or large rockets.  G/I based thrusters with million pound thrusts or larger are conceivable and probably buildable once the G/I sciences are fully understood.  When creating a new science and technology, we take baby steps before we walk, and we have to walk before we run, but IMO we have at least taken the first few steps in this new journey.


I was thinking near term as for now we're limited to a few hundred kilowatts max with on board power supplies due to cooling needs.

Still it would be neat to put one on a microsat give a KW or so of power and see if you can rise the orbit a little.

Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #255 on: 04/19/2009 05:54 PM »
"Still it would be neat to put one on a microsat give a KW or so of power and see if you can rise the orbit a little."

That's a TRL 7 exercise.  If we had the money to do something like that, I think we'd be investing in better materials, have much higher thrust efficiencies and probably build a 3D platform one could drive around inside and outside ISS.  That would make for a better demonstration as one would be showing a higher level of mastery.  Also, for a short term demo, you can use batteries instead of expensive PV arrays.

Offline mlorrey

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Re: Propellantless Field Propulsion and application
« Reply #256 on: 04/19/2009 08:00 PM »
Seems like small thrusts are possible.  What you need on a long interstellar flight.  Pico-Newtons aren't very much.  About the power supply: it's good that it's potentially simple.  I have an old tube Mac that probably would be too heavy to levitate itself, but I bet it could climb up a cable to the Moon.

Anyhow, the power supply so far is attached to a cable, and the demonstrated force experiments are more like a balance beam, I gather.

I like the idea of research for it's own sake, and it's true that investors frown upon an inventor changing his direction without their assent.  But I still don't get it.  Is this technology at the proof of concep phase?

Now to read IAC- 08 – C4.4.7.

Woodward's thruster work is at the TRL 5-6.  There have been many sorts of "proof of concept."  The issue here is that science doesn't actually ever "prove" anything.  More what it does is disprove all the alternatives.  So point in fact, there is no one single standard of evidence that qualifies as 'scientific", etc.  What we have are many people from many backgrounds who each individually think one level of evidence is convincing and another compelling, etc.  So the goal is to compile as many sorts of evidence as possible.

The rotator evidence is very compelling to me since I understand there are no other proposed effects found in anti-phase to electrostriction that can explain Jim's findings.  So far as convincing the larger scientific community is concerned, there's no way to tell how physicists will respond.  In general they don't like each other.  :-) 

Read a quote today that the field of economics "advances one funeral at a time". This is IMHO the way too much science in long established fields tends to progress.

Physics especially. Looking back at the transition between the era of relativity to the era of quantum theory shows this to be particularly true. Einstein and a few Maxwellian types held back much quantum theory in the 1920s through the 40's when they died off finally.

It is amazing today that you meet people who insist that you comply with a simplistic misinterpretation of Newton when he's three centuries dead. FYI while Newton wasn't fully supplanted by relativity or quantum theory, problems with Newton were refined (for instance, Mercury's orbit, among a number of other things).

If some folks here insist that Mercury obeyed Newton precisely then they'd have to accept there was some other force changing its orbit or that astronomers were insane. Folks need to stop demanding the same of gravinertial thrusters.
« Last Edit: 04/19/2009 08:01 PM by mlorrey »
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Offline JohnFornaro

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Re: Propellantless Field Propulsion and application
« Reply #257 on: 04/20/2009 12:10 AM »
What I hear you not saying is that the power supply is still an issue.  And with the reported thrust levels so low, the power supply seems to be adding more mass than the device can push against.  At least push against usefully.

I understand that tweaking satellite orbits by use of PV panels for energy supply, and only needing small bursts
for useful work is a good use of this device.
Sometimes I just flat out don't get it.

Offline GI-Thruster

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Re: Propellantless Field Propulsion and application
« Reply #258 on: 04/20/2009 01:45 AM »
"What I hear you not saying is that the power supply is still an issue.  And with the reported thrust levels so low, the power supply seems to be adding more mass than the device can push against."

John, the question you're asking has been answered many times in this thread.  To recap, what you're asking about is what we call "thrust efficiency" which is a measure of the amount of thrust (measured in Newtons or "N") for the amount of electrical power (measured in watts or "W") supplied to the test item.  The test items run by Jim have a thrust efficiency too low to enable human spaceflight but could be used for things like satellite station keeping.

Now there's a huge difference between the thrust efficiencies found in test items in the lab, and the thrust efficiencies possible.  Star Drive just answered this question a couple days ago when he said that we know of no theoretical limit to how efficient these items can be.  So, in order to illustrate what is possible, and even probable, Star Drive (AKA Paul March) wrote his "WarpStar" paper a couple years ago and presented it at STAIF '07.  It was extremely well received and if you read above, you can find a link to the paper.

But in short, if we presume a specific thrust efficiency of 1 newton per watt (1N/W) then we can use this to extrapolate how this might enable human spaceflight.  This is the thrust efficiency figure chosen by Paul in the WarpStar 1 design and there are no reasons to believe this is an unrealistic figure.

So that you know what we're talking about, the WarpStar craft is designed to accelerate constantly between the Earth and the Moon.  It can provide constant acceleration based upon the power systems of the design and fly from the Earth to the Moon in about 5 hours, or less if you don't mind a higher acceleration.  It can unload several tons of cargo and fly back in 5 hours, only then to be refueled.  Since it doesn't need to make a hypersonic reentry, it can be refueled in just a few minutes, have its life support refreshed and be off for another round trip with almost no maintenance.  It's capable of VTOL with no downwash or exhaust and can be parked in a space the size of a medium business jet.  It can be used as a lunar sky crane for assembling large structures on the Moon.  All this is possible with the simple power systems available with hydrogen fuel cells.  A similar craft with 1N/W thrusters could be powered by a small fission reactor and have complete autonomy in our planetary system so far as propulsion needs are concerned.  It could fly to Mars at its closest approach in 2 days, or at its furthest in 5 days.  It could fly to the asteroid belt in 6 days or to Jupiter in 7 or to Saturn and a nice view of the rings in 9 days and such a craft could be designed to stay out for many months at a time, much like modern naval vessels.

What you need to understand is that thrust efficiency is the question you've now asked several times and you haven't understood the answer.  The answer is that these lab test items do not have the thrust efficiency to enable human spaceflight but they are proving the science necessary to develop those that could.

Hope that answers your question.
« Last Edit: 04/20/2009 03:05 AM by GI-Thruster »

Offline blazotron

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Re: Propellantless Field Propulsion and application
« Reply #259 on: 04/20/2009 08:46 AM »
So what do you consider “substance” in regards to proving these observed M-E effects are REAL?  Supporting experimental data from two or more different sources used to be considered substantiating support, but apparently that is no longer the case in 2009.  So what will it take to prove the point to you and the rest of the skeptics in the world that the M-E or its QVF cousin is real and usable?

I am not a sceptic, I would be *happy* if someone will prove that 3rd law of Newton can be worked around.

It can be the case that the idea, being rather radical, does require verification by more than one team. Extraordinary claims do require extraordinary evidence, in this case, reproduction of the effect by multiple teams.

Do not assume that "they" (meaning scientific community) have ill intentions. No amount of complaining that "they" don't take it seriously would help. Ony more independent verifications will.

Firstly, please stop asserting that M-E gets 'around' Newtons third law any more than a game of tug-of-war does. The M-E reacts against the rest of the universe, period. While I understand thats a bit big of a concept for some folks, honestly though, it shouldn't be for anybody who has moved beyond the idea that anything outside our solar system is just little light bulbs on a big sphere.

By what mechanism is it reacting against the rest of the universe?  Why do other devices not react with the rest of the universe like this?  Why is this one special?  How can it instantaneously signal the rest of the universe to react?  Saying it is so doesn't make it so. 

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