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#180
by
VAXHeadroom
on 14 Dec, 2015 22:03
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...I found particularly interesting one mode posted by Shell before that had what appeared to be a traveling mode. It had dual input wave-guides and a mode that appeared at the bottom and then traveled up. I was wondering if a mode such as that might be difficult to generate with an antenna. I am not sure if it was but I suspected an asymmetry. What would be desired is an asymmetry of force on the cavity. Warptech pointed out to me in a video that David states if they used a dielectric between the elements that it wouldn't get propulsion unless it was water. If water would be pushed in the opposite direction as propulsion via the electro-magnetic fields and water has a dielectric constant then I believe space also has a permittivity. One could then possibly think of space as being the water and it is being pushed in the opposite direction as propulsion. If space as a dielectric was indeed being pushed one would have to ask if it could be pushed through the cavity walls. I also question if a stable mode is what is really desired to be generated. Maybe that is why some success has been achieved with magnetrons. I think one can think of a gradient in the dielectric constant of free space as an effect of gravity leading to gravitational lensing. A gap between two plates with the casimir force, where radiation is lacking, may also possibly be thought of as differences in the dielectric constant of space between and outside the plates which would correspond to energy density.
Some ideas that come to mind are the Dynamical Casimir Effect: https://goo.gl/A5jUd6
Something interesting I found on the effect of gravity on the dielectric constant of space and gravity slowing down light and or dragging space: https://goo.gl/oZxyvB P.S. I don't think we can detect locally this change in the speed of light because distance contracts with light slowing down so effectively it dosn't change speed locally, only non-locally). One of the reasons why I am not sure LIGO will be able to detect gravity waves but maybe I don't know enough about it.
Here is a paper I found on (asymmetric, anti-symmetric, symmetric modes) generated by light on cavities: https://goo.gl/tTf0Ap
I'll attach an image of one of my hope in generating such an asymmetry. The idea behind it is normally the electric and magnetic force oppose each other in a phased array antenna but with counter-winding of the phased array antennas the interaction of the magnetic field can be reversed so that the effect of charge separation works with the magnetic effects. The only problem being how to achieve such currents in wires at microwave wavelengths. Maybe why Transverse electric effects are so successful in the frustum is because (if it works) it avoids charge separation in the frustum so that the magnetic effects don't work against the electric charge separation in the cavity walls.
If we can say the cavity is some how pushing on space time then maybe we can avoid the whole CoM issue.
OK, but then the proponents need to address the objections based on frame-indifference (is there a privileged frame? which frame? and why?) and conservation of energy, previously discussed by Frobnicat and DeltaMass.
I am not sure it would work but one might consider the preferred frame at the edge of an event horzion as moving at the speed of light and as such light can't escape. That is if gravity actually drags space time for some reason. Problem is that suggests light going into the black hole could non-locally exceed the speed of light. I would think rather light should slow down near the event horizon till it comes to a stand-still. Maybe this makes sense if the non-local space is moving at the speed of light into the event horizon and that the light in that space, as a result, is time dilated and there fore, stands still. Maybe then away from gravity the space time is at rest with respect to the universe as a whole and contained in our sphere of the CMB? I am just guessing here.
I saw that video when it was first shared. Fascinating concept. What strikes me here is that electricity in copper travels at just about exactly 0.5c (~6ns/ft). In a frustum with the antennas in the back, any electric field that gets induced into the copper will essentially be out of phase at the small end since the waves in the cavity travel at c. Won't this create an opposing magnetic field on the small end while generating an in-phase magnetic field on the big end? I'm sure that's WAY too simple a description - (my defense is I'm a software engineer, not a physicist
)
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#181
by
rfmwguy
on 14 Dec, 2015 22:12
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(...)
p.s. There "ain't no way" I'm going to speculate on what it is...not yet. We either believe it works or we don't...or better yet...keep our minds open.
This is no theory but just looking at things that stand out from some simple questions and facts we know.
I'm moving operations into the area I've set aside in my home. I'll post more later.
I agree shell...that's the best way to look at it...unfortunately for me, I've ready only a few papers recently and they took me down several rabbit-holes. One of them today was a quantum vacuum photon paper here:
http://arxiv.org/abs/1511.07849Seems to be a credible theory for nanometer-scale reference frames, but practical at macro-scale? I doubt it. Face it Shell, there just isn't anything that jumps out at you and me...no "aha" type paper.
There are brain trusts here that are taking mental notes on our musings...something will break through soon, I hope.
Good luck on your home remodeling project! You've been busy, I know, but I'm going to send you some coal for your stocking if we don't see some pics soon
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#182
by
SeeShells
on 14 Dec, 2015 22:59
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(...)
p.s. There "ain't no way" I'm going to speculate on what it is...not yet. We either believe it works or we don't...or better yet...keep our minds open.
This is no theory but just looking at things that stand out from some simple questions and facts we know.
I'm moving operations into the area I've set aside in my home. I'll post more later.
I agree shell...that's the best way to look at it...unfortunately for me, I've ready only a few papers recently and they took me down several rabbit-holes. One of them today was a quantum vacuum photon paper here:
http://arxiv.org/abs/1511.07849
Seems to be a credible theory for nanometer-scale reference frames, but practical at macro-scale? I doubt it. Face it Shell, there just isn't anything that jumps out at you and me...no "aha" type paper.
There are brain trusts here that are taking mental notes on our musings...something will break through soon, I hope.
Good luck on your home remodeling project! You've been busy, I know, but I'm going to send you some coal for your stocking if we don't see some pics soon
Oh my mess I just made??!!! Pictures??? I get some after I put the mess back together. We have several days of cold temps hitting and snow so I can work on getting it up to snuff.
I'm currently digging my way through a paper that is hitting hard and ringing many bells, but we'll see.
Shell
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#183
by
Davinator
on 14 Dec, 2015 23:27
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Stepping it to note that any uncivil posts will be removed. This thread is not above the site rules.
New people should check out the opening post, and perhaps use the entry level thread, because jumping into this thread because you read that joke of an article on Wired does not give you the right to jump into this ongoing update thread saying "There's no warp drive??? Fake!!"
Also, please do not "multiquote" to the post you have lots and lots of quotes in a response. It makes it all very hard to read the thread.
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#184
by
rfmwguy
on 14 Dec, 2015 23:59
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Stepping it to note that any uncivil posts will be removed. This thread is not above the site rules.
New people should check out the opening post, and perhaps use the entry level thread, because jumping into this thread because you read that joke of an article on Wired does not give you the right to jump into this ongoing update thread saying "There's no warp drive??? Fake!!"
Also, please do not "multiquote" to the post you have lots and lots of quotes in a response. It makes it all very hard to read the thread.
Well, I was asleep at the switch on this one...just reviewed my notices (yeah I am not always online)...Thanks for stepping in. Understand the cleanup, thanks...whomever you are
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#185
by
rfmwguy
on 15 Dec, 2015 00:13
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Slight diversion here...I'd like to plug the L2 section and membership to this overall site. Even if you sign up for a couple of months as a trial, you'll get more info than you can handle...trust me...I can't even begin to scratch the surface.
Specifically, what I found is a very clean, almost precision level of no-nonsense posting regarding upcoming launches and ongoing missions. I was surprised to find NSF exclusive videos in there are well. Historic pics, etc.,
Think
we all here on this thread need to support the overall site and L2 it for the latest and greatest. Who knows, perhaps someday emdrive might have their own L2 thread discussing insider info and mission status should the thing become scaleable and useable for space exploration.
In the meantime, we'll do our humble best here...but consider supporting NSF.
<Nope, I know what you're thinking - I made this post without any pressure from NSF, they don't play that way>
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#186
by
TheTraveller
on 15 Dec, 2015 01:08
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#187
by
dustinthewind
on 15 Dec, 2015 01:36
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...
If we can say the cavity is some how pushing on space time then maybe we can avoid the whole CoM issue.
OK, but then the proponents need to address the objections based on frame-indifference (is there a privileged frame? which frame? and why?) and conservation of energy, previously discussed by Frobnicat and DeltaMass.
I am not sure it would work but one might consider the preferred frame at the edge of an event horzion as moving at the speed of light and as such light can't escape. That is if gravity actually drags space time for some reason. Problem is that suggests light going into the black hole could non-locally exceed the speed of light. I would think rather light should slow down near the event horizon till it comes to a stand-still. Maybe this makes sense if the non-local space is moving at the speed of light into the event horizon and that the light in that space, as a result, is time dilated and there fore, stands still. Maybe then away from gravity the space time is at rest with respect to the universe as a whole and contained in our sphere of the CMB? I am just guessing here.
Some possible support for the CMB as an absolute reference frame for space time.
http://physics.stackexchange.com/questions/25928/is-the-cmb-rest-frame-special-where-does-it-come-fromI think this guy is also arguing the same. I can't suggest it is 100% accurate but it looks legit at first glance.
https://scholar.google.com/scholar?cluster=11591112244843703577&hl=en&as_sdt=5,48&sciodt=0,48If our space in a gravity well is flowing into the earth with respect to the space of the universe then as we rotate through our gravity well we may observe a slight shift in the dipole of the CMB as the earth rotates but I would have no idea if it would be something that would be observable or not with our weak gravity well compared to that of a large one.
One of my fav songs Dustinthewind... I would agree with you but to see what is really happening you need to look at the frustum in X,Y and Z slices and tell me how many modes of operation do you see. https://drive.google.com/drive/folders/0B1XizxEfB23tbVYwc1Nsa29yZlk
Thanks, my dad used to sing that too me as a small one and it had similarity to my name. Some people think of the song as depressing and suggestive of our limited time but I like to think of it as us being the children of stars. Star children who are made of the dust of stars caught up in the solar winds of space and time. It gives it sort of an exotic feel.
I agree on the need to see more dimensions as I was wondering about the 3D nature. Thanks for the link. It looks complicated but it is apparent the simulation was run with a wave-guide included. I guess I would try and use a wave-guide as simulated to reproduce the modes. It almost looks like you might be able to excite it with an X shaped antenna through the bottom plate which is made of two T's. The current would be moving out on one T and current moving in on the other T but I can't say for sure. Possibly confirmed by SEZ_vu-ez.gif but the bottom plate (Bez_vu_ez.gif) looks a bit different.
I would guess there are others that know more about this than I would.
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#188
by
SeeShells
on 15 Dec, 2015 02:00
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...
If we can say the cavity is some how pushing on space time then maybe we can avoid the whole CoM issue.
OK, but then the proponents need to address the objections based on frame-indifference (is there a privileged frame? which frame? and why?) and conservation of energy, previously discussed by Frobnicat and DeltaMass.
I am not sure it would work but one might consider the preferred frame at the edge of an event horzion as moving at the speed of light and as such light can't escape. That is if gravity actually drags space time for some reason. Problem is that suggests light going into the black hole could non-locally exceed the speed of light. I would think rather light should slow down near the event horizon till it comes to a stand-still. Maybe this makes sense if the non-local space is moving at the speed of light into the event horizon and that the light in that space, as a result, is time dilated and there fore, stands still. Maybe then away from gravity the space time is at rest with respect to the universe as a whole and contained in our sphere of the CMB? I am just guessing here.
Some possible support for the CMB as an absolute reference frame for space time. http://physics.stackexchange.com/questions/25928/is-the-cmb-rest-frame-special-where-does-it-come-from
I think this guy is also arguing the same. I can't suggest it is 100% accurate but it looks legit at first glance. https://scholar.google.com/scholar?cluster=11591112244843703577&hl=en&as_sdt=5,48&sciodt=0,48
If our space in a gravity well is flowing into the earth with respect to the space of the universe then as we rotate through our gravity well we may observe a slight shift in the dipole of the CMB as the earth rotates but I would have no idea if it would be something that would be observable or not with our weak gravity well compared to that of a large one.
One of my fav songs Dustinthewind... I would agree with you but to see what is really happening you need to look at the frustum in X,Y and Z slices and tell me how many modes of operation do you see. https://drive.google.com/drive/folders/0B1XizxEfB23tbVYwc1Nsa29yZlk
Thanks, my dad used to sing that too me as a small one and it had similarity to my name. Some people think of the song as depressing and suggestive of our limited time but I like to think of it as us being the children of stars. Star children who are made of the dust of stars caught up in the solar winds of space and time. It gives it sort of an exotic feel.
I agree on the need to see more dimensions as I was wondering about the 3D nature. Thanks for the link. It looks complicated but it is apparent the simulation was run with a wave-guide included. I guess I would try and use a wave-guide as simulated to reproduce the modes. It almost looks like you might be able to excite it with an X shaped antenna through the bottom plate which is made of two T's. The current would be moving out on one T and current moving in on the other T but I can't say for sure. Possibly confirmed by SEZ_vu-ez.gif but the bottom plate (Bez_vu_ez.gif) looks a bit different.
I would guess there are others that know more about this than I would.
We don't know more trust me, you're very sharp and it's refreshing. It's always intrigues me, here we are star stuff, contemplating star stuff. That's heavy.
You are seeing my build with the dual opposing waveguides. The reason it differs from other builds that we have seen with waveguides is because off the top section I have a tuning chamber that allows me to run through multiple modes and even the effects they can have on one another as the tune progresses from one to the other. The waveguides will allow the multiplicity of modes through the tuning. I was pretty jazzed it gives me the ability to do that, antennas can't do that. Not sure what I'll find in generated thrust profiles and it progresses through tuning but it will be good data.
Shell
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#189
by
VAXHeadroom
on 15 Dec, 2015 02:03
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...
I agree on the need to see more dimensions as I was wondering about the 3D nature. Thanks for the link. It looks complicated but it is apparent the simulation was run with a wave-guide included. I guess I would try and use a wave-guide as simulated to reproduce the modes. It almost looks like you might be able to excite it with an X shaped antenna through the bottom plate which is made of two T's. The current would be moving out on one T and current moving in on the other T but I can't say for sure. Possibly confirmed by SEZ_vu-ez.gif but the bottom plate (Bez_vu_ez.gif) looks a bit different.
I would guess there are others that know more about this than I would.
I did a 3D animation of this data...
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#190
by
RERT
on 15 Dec, 2015 10:40
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Hi. Dr. Rodal at post 163: 'nothing in the cosmos...self-accelerating...'. You were discussing something completely different, but reminded me of this thought.
Shells almost said it at post 169, but Galaxies are accelerating away from each other now. If I understand right, Dark Energy is the name of the invisible and undetected thing we invented to balance the books to preserve our conservation laws in the face of this observation.
This may rank as a blindingly obvious remark, but if the EMDrive effect turns out to be real there will be a scramble to identify the balancing item, and CoM and CoE will remain intact, just slightly modified. This has happened before in other contexts, and most likely will happen again.
Cheers,
R.
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#191
by
Rodal
on 15 Dec, 2015 11:55
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Hi. Dr. Rodal at post 163: 'nothing in the cosmos...self-accelerating...'. You were discussing something completely different, but reminded me of this thought.
Shells almost said it at post 169, but Galaxies are accelerating away from each other now. If I understand right, Dark Energy is the name of the invisible and undetected thing we invented to balance the books to preserve our conservation laws in the face of this observation.
This may rank as a blindingly obvious remark, but if the EMDrive effect turns out to be real there will be a scramble to identify the balancing item, and CoM and CoE will remain intact, just slightly modified. This has happened before in other contexts, and most likely will happen again.
Cheers,
R.
Yes, in the end the big difference is that the evidence for acceleration of the expansion of the Universe is well accepted by scientists as evidenced by observations of supernovae, reconciliation of the measured geometry of space with the total amount of matter in the universe (cosmic microwave background) , analysis of large-scale structure, and of observational Hubble constant data. All of this has been published in excellent peer-reviewed journals and professionally analyzed.
On the other hand, evidence for self-acceleration of the EM Drive is very weak and objectionable: thermal effects have insufficiently been accounted for in most EM Drive experiments. Thermal effects have not been analyzed in the published reports: no one has conducted Computational Fluid Dynamics analysis to analyze natural thermal convection, no one has published thermal expansion analysis and measurements. Only two experimenters (and very recently) have performed tests in vacuum: NASA and Tajmar. Yang and Shawyer have failed to conduct a single experiment in vacuum. Shawyer has stated words to the effect that unless there is some vibration or nudging, experiments give zero forces. NASA has not yet published their experiments in peer-reviewed journals and NASA has not yet published their experiments in vacuum in any form (we only know of them through these NSF thread communications). NASA's experimental force measurements in vacuum (communicated to these threads) are orders of magnitude smaller than what was claimed by Shawyer and Yang: they could be the result of forces created by thermal expansion, due to microwave induction heating. Tajmar's experimental measurements in vacuum at TU Dresden are even smaller and Tajmar concludes
"our test campaign can not confirm or refute in any way the claims of the EMDrive".
So, the bottom line is that the test campaigns conducted so far have failed to demonstrate the claims of anomalous EM Drive forces (they have failed to demonstrate that they cannot be explained by classical conventional effects that render it of no use for space travel) . To make things worse, the initial claims for anomalous EM Drive forces (Shawyer's "theory") were based on serious misunderstandings (conflation of open waveguides with closed cavities, ignoring the balancing radiation pressure on the side walls of the EM Drive, etc.), and there is no compelling theory showing why a closed, geometrically asymmetric cavity excited by microwave radiation should result in self-acceleration useful for spaceflight. (Prof. Woodward thinks that if the NASA experiments show an anomalous force, that it must be due to NASA's use of a dielectric insert and Woodward's Mach Effect. Dr. White rejects Shawyer's and Yang's "theories" and instead proposes a Quantum Vacuum theory that has met opposition from others based on the immutability of the quantum vacuum.)
There were some very interesting (experimental and theoretical) discussions with Paul March (NASA) in previous threads but those exchanges, unfortunately, have stopped some time ago. Fifteen years after formation of SPR Ltd., scientific confirmation of anomalous forces from the EM Drive remains unfulfilled.
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#192
by
rfmwguy
on 15 Dec, 2015 12:41
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Computational Fluid Dynamics analysis to analyze natural thermal convection, no one has published thermal expansion analysis and measurements that can be reviewed. - doc
Ok doc, nice points but we need more specifics...what software is needed for these tests and can you help us calculate a vertical lift component for balance beam measurements?
We've already determined lorentz is minimal in horizontal measurements in ambient atmosphere, would you agree that these two elements would be the last pieces of the puzzle?
Shell and I would need your help with the fluid dynamics and thermal expansion calcs...sound like fun?
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#193
by
Rodal
on 15 Dec, 2015 12:54
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Computational Fluid Dynamics analysis to analyze natural thermal convection, no one has published thermal expansion analysis and measurements that can be reviewed. - doc
Ok doc, nice points but we need more specifics...what software is needed for these tests and can you help us calculate a vertical lift component for balance beam measurements?
We've already determined lorentz is minimal in horizontal measurements in ambient atmosphere, would you agree that these two elements would be the last pieces of the puzzle?
Shell and I would need your help with the fluid dynamics and thermal expansion calcs...sound like fun?
There are several software packages for computational fluid dynamics that I specifically discussed: for example ANSYS CFX and ANSYS FLUENT CFD. The hardware computational resources and professional expertise for such analysis make the Meep analysis discussed here pale in comparison. The Navier Stokes equations are nonlinear while Maxwell's equations are linear.
Closed-form solution of the Navier Stokes equations is out of the question (except for some very simplistic cases not applicable to these experiments). Just making progress towards a mathematical theory that will give insight into these equations is so difficult that it constitutes an (unachieved) Millenium Prize Problem, with a 1 million dollar prize ! (
https://en.wikipedia.org/wiki/Millennium_Prize_Problems).
As previously discussed the most effective way to deal with thermal convection effects is either by testing in vacuum (as done by Tajmar and NASA) or by testing EM Drive forces large enough that they clearly stand above any thermal effects (as proposed by the Canadian team). Several people in these threads have proposed interesting ideas to at least quantify and minimize thermal convection effects, that have not yet been addressed (identical magnetron heated EM Drives at both ends of a balanced beam, with only one exciting the interior of the cavity, etc.)
Testing in a vacuum (or performing computational fluid mechanics analysis) only addresses the thermal convection effects, it does not address thermal expansion effects due to microwave induction heating.
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#194
by
ThereIWas3
on 15 Dec, 2015 12:56
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A magnetron is pretty darn close to a radio frequency (RF) white noise source. Not as good as a noise diode, but pretty damn close. Think Ella Fitzgerald trying to break the wine glass by hissing at it.
Especially a "free running" magnetron with no frequency-control feedback. Nobody uses vacuum-tube osciallators any more for good reason. All modern radio transmitters use synthesizers locked to a temperature-controlled reference crystal.
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#195
by
rfmwguy
on 15 Dec, 2015 13:10
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(...)Computational Fluid Dynamics analysis to analyze natural thermal convection, no one has published thermal expansion analysis and measurements that can be reviewed. - doc(...)
There are several software packages for computational fluid dynamics that I specifically discussed: for example ANSYS CFX and ANSYS FLUENT CFD. The hardware computational resources and professional expertise for such analysis make the Meep analysis discussed here pale in comparison. The Navier Stokes equation are nonlinear while Maxwell's equations are linear.
As previously discussed the most effective way to deal with thermal convection effects is either by testing in vacuum (as done by Tajmar and NASA) or by testing EM Drive forces large enough that they clearly stand above any thermal effects (as proposed by the Canadian team). Several people in these threads have proposed interesting ideas to at least quantify and minimize thermal convection effects, that have not yet been addressed (EM Drives at both ends of a balanced beam, only one exciting the cavity, etc.)
Testing in a vacuum (or performing computational fluid mechanics analysis) only addresses the thermal convection effects, it does not address thermal expansion effects due to microwave induction heating.
Yikes...not for diyers...ok let's boil this down abit.
Would you agree that the Li's paper positing lorentz force describing a torsional (rotary) force of up to a few micronewtons is irrelevant for horizontal beam measurements?
If so, would you agree that experimenters using horizontal beams without a vacuum only have fluid dynamics or thermal expansion analysis to overcome?
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#196
by
OnlyMe
on 15 Dec, 2015 13:42
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Hi. Dr. Rodal at post 163: 'nothing in the cosmos...self-accelerating...'. You were discussing something completely different, but reminded me of this thought.
Shells almost said it at post 169, but Galaxies are accelerating away from each other now. If I understand right, Dark Energy is the name of the invisible and undetected thing we invented to balance the books to preserve our conservation laws in the face of this observation.
This may rank as a blindingly obvious remark, but if the EMDrive effect turns out to be real there will be a scramble to identify the balancing item, and CoM and CoE will remain intact, just slightly modified. This has happened before in other contexts, and most likely will happen again.
Cheers,
R.
Dark energy as an unknown variable, is not to preserve conservation laws, it is an adjustment intended to preserve the validity of general relativity at the scales of the observed acceleration.
The terms
dark energy and
dark matter have become so common, the reason they are called dark is not always clear. They are names assigned to unknown variables, whose purpose is to compensate for the fact that without them, our best model of gravitation general relativity, fails to accurately describe what we observe...
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#197
by
Rodal
on 15 Dec, 2015 13:49
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(...)Computational Fluid Dynamics analysis to analyze natural thermal convection, no one has published thermal expansion analysis and measurements that can be reviewed. - doc(...)
There are several software packages for computational fluid dynamics that I specifically discussed: for example ANSYS CFX and ANSYS FLUENT CFD. The hardware computational resources and professional expertise for such analysis make the Meep analysis discussed here pale in comparison. The Navier Stokes equation are nonlinear while Maxwell's equations are linear.
As previously discussed the most effective way to deal with thermal convection effects is either by testing in vacuum (as done by Tajmar and NASA) or by testing EM Drive forces large enough that they clearly stand above any thermal effects (as proposed by the Canadian team). Several people in these threads have proposed interesting ideas to at least quantify and minimize thermal convection effects, that have not yet been addressed (EM Drives at both ends of a balanced beam, only one exciting the cavity, etc.)
Testing in a vacuum (or performing computational fluid mechanics analysis) only addresses the thermal convection effects, it does not address thermal expansion effects due to microwave induction heating.
Yikes...not for diyers...ok let's boil this down abit.
Would you agree that the Li's paper positing lorentz force describing a torsional (rotary) force of up to a few micronewtons is irrelevant for horizontal beam measurements?
If so, would you agree that experimenters using horizontal beams without a vacuum only have fluid dynamics or thermal expansion analysis to overcome?
I am not familiar with a paper from Li on Lorentz forces for torsional pendulums. I recall that Frobnicat discussed electromagnetic forces on NASA's torsional pendulum in very early threads, and we discussed the effects of the magnetic damper early on (in thread #2 or earlier), including several discussions with Paul March (NASA) in earlier threads.
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#198
by
rfmwguy
on 15 Dec, 2015 13:55
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#199
by
Tellmeagain
on 15 Dec, 2015 13:55
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Would you agree that the Li's paper positing lorentz force describing a torsional (rotary) force of up to a few micronewtons is irrelevant for horizontal beam measurements?
rfmwgy, I appreciate your doing your own experiment. I read NFS occasionally, and happen to see your question when I am having a sick leave today. Actually our paper (the Li's paper) had shown Lorentz force up to 41 micro-Newtons (see fig 4 of the paper), and that was with the NASA style second generation damper. If we use NASA's first generation damper, that number can be easily doubled or even tripled. Yes, I believe all NASA saw in their 2014 paper were Lorentz force. The ball is now in NASA's court. They need to address this issue in their next paper. Are there ways to eliminate/control for Lorentz force in an experiment? Yes, there are, but they missed that in their 2014 paper.
)
