Talk-Polywell.org

chrismb wrote:I think you are talking about longitudinal forces.

There is a superb MSc thesis I found some time back that someone has looked into this. Very interesting read, very comprehensive:

http://www.df.lth.se/~snorkelf/Longitud ... utdok.html

Chris:

Thanks much for the pointer! And yes that is what I'm talking about, i.e., a longitudinal force that runs parallel to the current flow. As noted, it can be modeled as a current flow effect or magnetic field effect, but in either case it’s a force that tries to make a current loop into a minimum energy circle. In Woodward's case, the liquid metal contacts would not reduce this expansion force on their own, for that is done by how the wiring for same is twisted together and tied down to the torque pendulum arm, but they do prevent these longitudinal forces from being turned into a torque that could affect the torque pendulum’s thrust measurement results.

Best,

djolds1 wrote:

GIThruster wrote:But you can see why I no longer spend time over at NBF. . .

Brian Wang has a first-class SciTech News aggregation Metasite going at NBF. The forums are another issue.

True. There's everything to like about Brian. It's a terrible shame his forum is dominated by the habitually contentious.

chrismb wrote:

paulmarch wrote:BTW, concur on your summary about folks not taking the time and effort required to really understand a given test setup, yet thinking they know why it should or shouldn't work. Best to be humble in most things.

I will freely confess I have not looked into every detail of your work (and some here tell me that that means I should not engage in asking challenging questions until I know 'everything'!).

That's not the point, Chris. No one knows "everything". My point is, that GG over at NBF wants to dazzle with his opinions about the experimental setups. There's no point. Anyone doing a real investigation, meaning anyone doing "due diligence" on the work, will see that Jim has what he needs with the ARC Lite. Posturing about magnetic levitation as a means of doing experiments doesn't impress me, nor should it impress anyone else. To be plain: measurement apparatus need to be reliable, trustworthy and flexible in a host of ways. Jim puts all sorts of thrusters on his balance. Anyone who invests even a mediocre amount of time trying to understand the needs of the balance, would immediately note they can't use magnetic levitation. There are too many fields involved. The MLT runs on b-field, so why would you place it inside a powerful b-field just to levitate it? You'll get coupling. That's just stupidly looking for trouble.

One finds this sort of thing--uneducated opinions pretending to be valid criticism--all the time. People love to build vacuum chambers out of stainless steel, because it has such a low vapor pressure that it's easy to pump out. Trouble is, when you're dealing with high voltage or currents running through stainless, you create potentials and currents in the chamber itself. So, Jim and Paul have both wisely chosen to build chambers that don't have this trouble. Now an uneducated standerby, might offer that one could get a better vacuum with stainless than with acrylic or polycarb and he'd be right. He'd still be wrong that stainless is a better way to go, and if he were posting his opinion around on some blog, there's no end to the misunderstandings he might create.

People who devote thousands of hours of their lives to complex work don't deserve casual criticism. It's just the critics who think their opines worthy. They're usually not.

TallDave wrote:

93143 wrote:The energy that you pull out with your device brings the energy total back to the original level, but it's low-entropy, concentrated energy. (In theory (very simple, idealized theory), if it isn't heat, its entropy is lower than that of thermal energy at any temperature - electrical energy can theoretically be used at 100%.) So the total entropy is still lower in the ideal case.

Cogent as always.

Yes, I agree if the total energy was the same and the overall temp had not changed the overall entropy of the system would have decreased in violation of 2L -- but the general temp decrease doesn't have to be the same as the local energy increase. The Universe's temp has been decreasing since the Big Bang...

But can you use the expansion of space that way? It seems like in an expanding universe there ought to be some enthalpy in a nonzero-temp space even if it has uniform temp. Hmm.

Aha! I think you can.

Imagine you have a box, and early in the history of the Universe, say when the avg temp was 100 million degrees K, you put some universe-average matter in the box. Now, at the time you box it, the stuff in the box seems to have zero enthalpy -- you can't do any work with it, because it's at the same temp as the universe around it.

But sit on the box until today, when the average temp is just 3.7K (iirc), and now your box is chock-full of enthalpy just begging to do useful work... thanks to the expansion of space.

Of course, that should not be viewed as a decrease in the system's overall entropy... which sort of forces you to define enthalpy as an absolute, rather than relative, quantity. That is to say, the box always had the same enthalpy, the changing conditions just allowed us to harness it.

wouldn't the stuff in the box, along with the box expand as the universe expanded? If not, why not? Magic box?

bob

I wondered about that too, but no, it turns out the expansion of space pushes on fixed or gravitationally bound objects but does not make them larger: a fairly ordinary box will do.

http://en.wikipedia.org/wiki/Metric_exp ... turbations

A cosmological constant has the effect of a repulsive force between objects which is proportional (not inversely proportional) to distance. Unlike inertia it actively "pulls" on objects which have clumped together under the influence of gravity, and even on individual atoms. However this does not cause the objects to grow steadily or to disintegrate; unless they are very weakly bound, they will simply settle into an equilibrium state which is slightly (undetectably) larger than it would otherwise have been

Upon reflection, it's obvious the distribution of matter would look quite a lot different otherwise.

We are currently looking for a pair of inexpensive, (less than $2k each) LF/HF 500W, 10 kHz-to-5.0 MHz or so wideband width Piezoelectric/Laser driver power amps to replace Woodward's two current Carvin Audio amps. If anybody has a lead on such items please let us know the source of same.

Best,

Paul M.

Only heard back from one person who would know where to find some of those, but not for that cheap.. I'll keep asking around.

Seems like something interesting's happened:
http://forum.nasaspaceflight.com/index. ... #msg771796

the cleanest idea of using a battery powered device surrounded by a Faraday Cage didn't yield any thrust.
...
Yesterday Duncan Cumming emailed everyone on Woodward's list saying that his battery-powered device didn't work.

Thanks Betruger, interesting news.
Let's see if Paulmarch can give us more details on this.

Even if the ME conjecture will be proved as not working, it will be equally interesting to understand what they were really measuring in their previous experiments.

Now appears it was a mistake by that Dr Fuerst. The experiment he refers to as having been mentioned over the weekend was actually done years ago.

The work by Dr. Cummins was years ago. Dr. Fuerst just recently joined Jim's reading list and isn't up to date on either Jim's theory nor the experimental work over the years.

The only new work was what Jim completed a few weeks ago and about which he has not yet posted a final report. I can tell you though that he has 1 uN forces found on the ARC Lite which is able to resolve 10 nN forces. The thrust reversed as the phase between the 1w and 2w portions of the signal shifted, just as theory predicts. It likewise switched when the thruster was mechanically turned in direction, and it disappeared when the thruster was pointed 90* off axis (vertical rather than the horizontal mode the balance is designed to operate in.) This last is an excellent control, that functions as a perfect dummy load in order to eliminate spurious thrust sources. There weren't any.

If there's any problem with the state of the art in M-E work, it is that we really want to see much larger forces, and I think that is what Jim will be working on in the fall.

This is good. Because from what I have read, Woodward-Mach appears to be the only possibility for a breakthrough propulsion. If falsified, we can forget about breakthrough propulsion and hope that the EMC2 team is successful at realizing fusion power.

I have heard about "Dynamic Theory" and have read the pdf's. However, such appears to be very speculative at this time.

Ron,
That is pretty cool news. I liked the idea of the off-axis spurious thrust test. Glad to hear it worked out.

And now to move the coffee table...

GIThruster wrote:The work by Dr. Cummins was years ago. Dr. Fuerst just recently joined Jim's reading list and isn't up to date on either Jim's theory nor the experimental work over the years.

The only new work was what Jim completed a few weeks ago and about which he has not yet posted a final report. I can tell you though that he has 1 uN forces found on the ARC Lite which is able to resolve 10 nN forces. The thrust reversed as the phase between the 1w and 2w portions of the signal shifted, just as theory predicts. It likewise switched when the thruster was mechanically turned in direction, and it disappeared when the thruster was pointed 90* off axis (vertical rather than the horizontal mode the balance is designed to operate in.) This last is an excellent control, that functions as a perfect dummy load in order to eliminate spurious thrust sources. There weren't any.

If there's any problem with the state of the art in M-E work, it is that we really want to see much larger forces, and I think that is what Jim will be working on in the fall.

What are the specs for arc-lite measurement error due to rectification of large oscillating forces? That would not apply to your control.

The force is so small you would need to go over the whole setup with a toothcomb and more to eliminate error.

Of course, it would be great if this effect is real, but it does not seem likely. If it were real it would be a free energy source, since power can be extracted from an M-E device trivially.

tomclarke wrote:

GIThruster wrote:The work by Dr. Cummins was years ago. Dr. Fuerst just recently joined Jim's reading list and isn't up to date on either Jim's theory nor the experimental work over the years.

The only new work was what Jim completed a few weeks ago and about which he has not yet posted a final report. I can tell you though that he has 1 uN forces found on the ARC Lite which is able to resolve 10 nN forces. The thrust reversed as the phase between the 1w and 2w portions of the signal shifted, just as theory predicts. It likewise switched when the thruster was mechanically turned in direction, and it disappeared when the thruster was pointed 90* off axis (vertical rather than the horizontal mode the balance is designed to operate in.) This last is an excellent control, that functions as a perfect dummy load in order to eliminate spurious thrust sources. There weren't any.

If there's any problem with the state of the art in M-E work, it is that we really want to see much larger forces, and I think that is what Jim will be working on in the fall.

What are the specs for arc-lite measurement error due to rectification of large oscillating forces? That would not apply to your control.

The force is so small you would need to go over the whole setup with a toothcomb and more to eliminate error.

Of course, it would be great if this effect is real, but it does not seem likely. If it were real it would be a free energy source, since power can be extracted from an M-E device trivially.

How is that figured? Wouldn't momentum be conserved? You still need to apply power to the thing to get it to create motion.