Quote from: Notsosureofit on 10/07/2014 05:11 pmQuote from: Rodal on 10/07/2014 04:34 pmQuote from: Ron Stahl on 10/07/2014 04:29 pmI think that's unlikely. Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin. Paul believes both Woodward and White are correct. Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory. Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time. Teflon has a very poor k~2, but it is good up into microwave territory. Most ceramics the k drops off way before. In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal. They are certainly not using that.Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive). We didn't have your additional arguments.Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]Interested on what others think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric for NASA's truncated cone.http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19700003017.pdfGreat reference. See page 45 for Teflon. At 2Ghz it starts to get nonlinear, however this is at what amount of electric field and temperature?
Quote from: Rodal on 10/07/2014 04:34 pmQuote from: Ron Stahl on 10/07/2014 04:29 pmI think that's unlikely. Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin. Paul believes both Woodward and White are correct. Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory. Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time. Teflon has a very poor k~2, but it is good up into microwave territory. Most ceramics the k drops off way before. In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal. They are certainly not using that.Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive). We didn't have your additional arguments.Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]Interested on what others think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric for NASA's truncated cone.http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19700003017.pdf
Quote from: Ron Stahl on 10/07/2014 04:29 pmI think that's unlikely. Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin. Paul believes both Woodward and White are correct. Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory. Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time. Teflon has a very poor k~2, but it is good up into microwave territory. Most ceramics the k drops off way before. In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal. They are certainly not using that.Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive). We didn't have your additional arguments.Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]Interested on what others think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric for NASA's truncated cone.
I think that's unlikely. Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin. Paul believes both Woodward and White are correct. Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory. Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time. Teflon has a very poor k~2, but it is good up into microwave territory. Most ceramics the k drops off way before. In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal. They are certainly not using that.Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.
Quote from: Rodal on 10/07/2014 05:17 pmQuote from: Notsosureofit on 10/07/2014 05:11 pmQuote from: Rodal on 10/07/2014 04:34 pmQuote from: Ron Stahl on 10/07/2014 04:29 pmI think that's unlikely. Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin. Paul believes both Woodward and White are correct. Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory. Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time. Teflon has a very poor k~2, but it is good up into microwave territory. Most ceramics the k drops off way before. In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal. They are certainly not using that.Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive). We didn't have your additional arguments.Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]Interested on what others think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric for NASA's truncated cone.http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19700003017.pdfGreat reference. See page 45 for Teflon. At 2Ghz it starts to get nonlinear, however this is at what amount of electric field and temperature?Look around 30 GHz
Quote from: Notsosureofit on 10/07/2014 05:26 pmQuote from: Rodal on 10/07/2014 05:17 pmQuote from: Notsosureofit on 10/07/2014 05:11 pmQuote from: Rodal on 10/07/2014 04:34 pmQuote from: Ron Stahl on 10/07/2014 04:29 pmI think that's unlikely. Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin. Paul believes both Woodward and White are correct. Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory. Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time. Teflon has a very poor k~2, but it is good up into microwave territory. Most ceramics the k drops off way before. In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal. They are certainly not using that.Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive). We didn't have your additional arguments.Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]Interested on what others think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric for NASA's truncated cone.http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19700003017.pdfGreat reference. See page 45 for Teflon. At 2Ghz it starts to get nonlinear, however this is at what amount of electric field and temperature?Look around 30 GHzOK I'm back to this. Here I attach the graph showing the dielectric properties of Teflon vs frequency.@notsosureofit : why look at 30GHz if the NASA tests operated at 2 GHz? I propose the following: just like the glass transition temperature of polymers shift with the WLF equation, the dielectric properties also are a function of temperature and electric field
I'd be very interested to see the piezo and electrostrictive coefficients for this.
...PS: anyone been able to open p.17 of the report ? (OK 5th time never fails)
Well, on the teflon issue--a quick scan shows PTFE has a piezo coefficient about 2-3 orders below things like PZT, which is about 0.1%. According to this, it also has a good electrostrictive coefficient:http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=832050&url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F6733%2F18004%2F00832050.pdf%3Farnumber%3D832050And PTFE is easy to dope, so for example one could use the percolation threshold technique and Schottky Barrier to generate a very large k despite it has a crummy k. Given these, Teflon is not a bad choice for an M-E dielectric.We don't know if extrinsic contributions to k can be used for M-E generation. The materials science is just not there yet. In fact, what we want to do is use these mechanisms with materials we already know work, to determine more about how M-E is stored. However, given these extrinsic mechanism can store M-E, is is easy to see how it could be used especially at millimeter wave frequencies to get thrust. A simple sinewave is sufficient since the material itself has 1w piezo response and 2w electrostrictive response. If the piezo response is negative, the two will add rather than subtract where they overlap and pronounced effects should be observed. So if this is what Eagle is doing, I suggest dope the PTFE with carbon nanotubes and see if that doesn't jump the thrust several orders magnitude through percolation threshold contribution.
Quote from: Ron Stahl on 10/07/2014 07:26 pmWell, on the teflon issue--a quick scan shows PTFE has a piezo coefficient about 2-3 orders below things like PZT, which is about 0.1%. According to this, it also has a good electrostrictive coefficient:http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=832050&url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F6733%2F18004%2F00832050.pdf%3Farnumber%3D832050And PTFE is easy to dope, so for example one could use the percolation threshold technique and Schottky Barrier to generate a very large k despite it has a crummy k. Given these, Teflon is not a bad choice for an M-E dielectric.We don't know if extrinsic contributions to k can be used for M-E generation. The materials science is just not there yet. In fact, what we want to do is use these mechanisms with materials we already know work, to determine more about how M-E is stored. However, given these extrinsic mechanism can store M-E, is is easy to see how it could be used especially at millimeter wave frequencies to get thrust. A simple sinewave is sufficient since the material itself has 1w piezo response and 2w electrostrictive response. If the piezo response is negative, the two will add rather than subtract where they overlap and pronounced effects should be observed. So if this is what Eagle is doing, I suggest dope the PTFE with carbon nanotubes and see if that doesn't jump the thrust several orders magnitude through percolation threshold contribution.But, from my R&D work in polymers, PTFE properties are very dependent on temperature, strain rate, strain, and other variables. It is a thermoplastic, without any cross-linking. As @notsosureofit stated it will have very complicated properties. If it is doped the properties are going to be even more complicated (it will be inhomogenous and if loaded with carbon nannotubes it may become anisotropic if preferentially aligned). It would not be my first choice for an R&D program unless I would have a lab with a dielectrometer, FTIR, DSC, TGA, TMA, DTMA and an MTS to investigate its nonlinear properties as a function of several variables and fully characterize it...I have actually investigated the properties of polymers like this versus frequency (like p. 45 of this report) and I know that this tan delta curve (see below) is very dependent on other variables . Also, there are several qualities of PTFE in the market, who knows what kind of PTFE they actually had. But, as an empirical, approach, like Edison did so well for investigating materials for the light bulb, I think the idea of "suggest dope the PTFE with carbon nanotubes and see if that doesn't jump the thrust several orders magnitude through percolation threshold contribution." is a very good idea. The problem is that like Mulletron said, why didn't NASA run more experiments? It looks like it takes a long time to just run a few experiments and there are countless material choices to explore...
...Those graphs look like they are old and out of date. PTFE is widely used as a substrate in microwave pcbs and other places where its low loss over wide microwave frequencies is required. ..
Those graphs look like they are old and out of date. PTFE is widely used as a substrate in microwave pcbs and other places where its low loss over wide microwave frequencies is required. I extracted the following graph from this recent paper:www.radioeng.cz/fulltexts/2012/12_02_0551_0556.pdfWhen I have some time I will post some pictures of 900 MHz ceramic resonators. Every cell phone has a few of them inside. Cell phones would not be so slim and lightweight without them. It's possible they are using a 965 MHz ceramic filter in a frequency doubled mode.
The problem is that like Mulletron said, why didn't NASA run more experiments? It looks like it takes a long time to just run a few experiments and there are countless material choices to explore...
You might want to use a URL shortener for that PDF; it's breaking the forum formatting!
I was looking for any evidence that dark matter interacts with RF waves. This leads to considering the red shift as perhaps due to dark matter interaction.I found one guy who claims that dark matter does not exist, the missing mass is diatomic hydrogen. That was interesting so here is the link.http://www.newtonphysics.on.ca/hydrogen/I found another guy who claims that light interaction with dark matter does cause the red shift. That was more interesting because he gave some math. Under the constraints of his model, which seem valid for light in interstellar space, he gives the equation:dp/dt = -H p as the change in momentum, p, of a photon, where H is the Hubble constant equals about 2.2 x 10^-18 per second. Note that the value of H has been changing and being refined rapidly over the last few years. This value is from about 2013.The reason this is interesting is because this change in momentum attributed to dark matter implies an equal and opposite change in momentum in the dark matter. At this point I'm not going to derive the effect that this proposed coupling of RF wave photons and dark matter may have on the thruster cavity. It seems small though.Here is the link:http://arxiv.org/ftp/arxiv/papers/0704/0704.1044.pdf
More importantly:The movie, black and white, 16mm, introduced a number of things about physics, the most noteworthy being a room full of ping pong balls on loaded mousetraps. Mr. Baez threw in the first ping pong ball to start the chain reaction. It was spectacular. In one of the handful of brilliant moves that I've made here and there in the cosmos, I asked if we could see that part backwards. And lo, Athena smiled upon me, Mr. Russo granted permission, and the projectionist reversed the chain reaction to the point where the first ball magically flew back into Mr. Baez's hand. The class erupted in applause. I gotta hug from my would be GF at the time.