Quote from: SeeShells on 07/11/2015 12:57 amQuote from: deltaMass on 07/11/2015 12:48 amQuote from: SeeShells on 07/11/2015 12:42 amQuote from: deltaMass on 07/11/2015 12:30 amHere's the real problem - neither of us are professional physicists. We are both engineers (hardware/software/systems)HA! That never stopped me or my old business partner, he didn't have a degree, but he taught computer science at Case Western, he had patents up the kazzo at Motorola and the list goes on and he even routinely debated with Brian Green and sometimes won. Ack, degree. Shell I confess I do have an honours degree in Physics (Oxford, got a place when I was 16, my biggest claim to fame I suppose) but that was the sixties and I did get a bit... distracted. I also have about 18 patents. I'm a bit of a klutz with my hands, so experimental work is somewhat uphill sledding for me. But there's nothing like strong motivation to get me bending metal and soldering (I built my first radio aged nine). If I saw some decent experimental results coming out of the superb DIY community here, I'd be clearing off the dusty workbench in two shakes of a lamb's tail; you can take that to the bank.I'm going to do my absolute best to make you hold to that. I've never backed away from a challenge. I must admit you beat me out at 9 took me to 14-15 to do my first TV.Shell PS: Yep the 60's and 70's at the UofM were kinda spacy.An honours degree in Physics at Oxford? To me that's better than the real thing, very classy.Shell
Quote from: deltaMass on 07/11/2015 12:48 amQuote from: SeeShells on 07/11/2015 12:42 amQuote from: deltaMass on 07/11/2015 12:30 amHere's the real problem - neither of us are professional physicists. We are both engineers (hardware/software/systems)HA! That never stopped me or my old business partner, he didn't have a degree, but he taught computer science at Case Western, he had patents up the kazzo at Motorola and the list goes on and he even routinely debated with Brian Green and sometimes won. Ack, degree. Shell I confess I do have an honours degree in Physics (Oxford, got a place when I was 16, my biggest claim to fame I suppose) but that was the sixties and I did get a bit... distracted. I also have about 18 patents. I'm a bit of a klutz with my hands, so experimental work is somewhat uphill sledding for me. But there's nothing like strong motivation to get me bending metal and soldering (I built my first radio aged nine). If I saw some decent experimental results coming out of the superb DIY community here, I'd be clearing off the dusty workbench in two shakes of a lamb's tail; you can take that to the bank.I'm going to do my absolute best to make you hold to that. I've never backed away from a challenge. I must admit you beat me out at 9 took me to 14-15 to do my first TV.Shell PS: Yep the 60's and 70's at the UofM were kinda spacy.
Quote from: SeeShells on 07/11/2015 12:42 amQuote from: deltaMass on 07/11/2015 12:30 amHere's the real problem - neither of us are professional physicists. We are both engineers (hardware/software/systems)HA! That never stopped me or my old business partner, he didn't have a degree, but he taught computer science at Case Western, he had patents up the kazzo at Motorola and the list goes on and he even routinely debated with Brian Green and sometimes won. Ack, degree. Shell I confess I do have an honours degree in Physics (Oxford, got a place when I was 16, my biggest claim to fame I suppose) but that was the sixties and I did get a bit... distracted. I also have about 18 patents. I'm a bit of a klutz with my hands, so experimental work is somewhat uphill sledding for me. But there's nothing like strong motivation to get me bending metal and soldering (I built my first radio aged nine). If I saw some decent experimental results coming out of the superb DIY community here, I'd be clearing off the dusty workbench in two shakes of a lamb's tail; you can take that to the bank.
Quote from: deltaMass on 07/11/2015 12:30 amHere's the real problem - neither of us are professional physicists. We are both engineers (hardware/software/systems)HA! That never stopped me or my old business partner, he didn't have a degree, but he taught computer science at Case Western, he had patents up the kazzo at Motorola and the list goes on and he even routinely debated with Brian Green and sometimes won. Ack, degree. Shell
Here's the real problem - neither of us are professional physicists. We are both engineers (hardware/software/systems)
@Rodal re. Poynting vectors: What is the total duration of each series?
I stand with Woodward on his attitude to Shawyer. But all this is theory and to be frank I am still looking for something to make sense. I was about to say "However, Woodward would kill for Shawyer's thrust-to-power ratios" but there was a time, albeit very brief, when Woodward was measuring 15 mN of thrust from 1 KW input. He could never repeat it. Now he has Langmuir's Disease**, and is regularly down around 2 uN. My prognosis is that eventually, like the smile on the Cheshire Cat, the effect will vanish entirely. I would love to be wrong about that.**https://en.wikipedia.org/wiki/Pathological_science
Quote from: Ricvil on 07/10/2015 08:21 pmSomeone has the first 3 resonance frequencys of cavity with flat ends, and the frequency of the microwave source?Thanks.Perhaps this may help?http://forum.nasaspaceflight.com/index.php?topic=36313.msg1333246#msg1333246 Re: EM Drive Developments - related to space flight applications - Thread 2« Reply #775 on: 02/18/2015 12:32 PM »see "Frustrum modes overview 2A.pdf" attachment
Someone has the first 3 resonance frequencys of cavity with flat ends, and the frequency of the microwave source?Thanks.
Quote from: deltaMass on 07/11/2015 01:29 amI stand with Woodward on his attitude to Shawyer. But all this is theory and to be frank I am still looking for something to make sense. I was about to say "However, Woodward would kill for Shawyer's thrust-to-power ratios" but there was a time, albeit very brief, when Woodward was measuring 15 mN of thrust from 1 KW input. He could never repeat it. Now he has Langmuir's Disease**, and is regularly down around 2 uN. My prognosis is that eventually, like the smile on the Cheshire Cat, the effect will vanish entirely. I would love to be wrong about that.**https://en.wikipedia.org/wiki/Pathological_scienceDm,Congrats on ur self studies which have made u to a bonafide physics guru in my view. Purdue taught me aviation, life taught me rf, so understand it can be done on ur own.Regarding langmuirs disease, this perhaps is the most important thing we all should keep in mind, when research turns to advocacy, its time to research something else. This for ur insight...and advancing beyond a forum nickname. Keep us on track and don't be afraid to plant some seeds of ur own.
Quote from: rfmwguy on 07/11/2015 02:05 amQuote from: deltaMass on 07/11/2015 01:29 amI stand with Woodward on his attitude to Shawyer. But all this is theory and to be frank I am still looking for something to make sense. I was about to say "However, Woodward would kill for Shawyer's thrust-to-power ratios" but there was a time, albeit very brief, when Woodward was measuring 15 mN of thrust from 1 KW input. He could never repeat it. Now he has Langmuir's Disease**, and is regularly down around 2 uN. My prognosis is that eventually, like the smile on the Cheshire Cat, the effect will vanish entirely. I would love to be wrong about that.**https://en.wikipedia.org/wiki/Pathological_scienceDm,Congrats on ur self studies which have made u to a bonafide physics guru in my view. Purdue taught me aviation, life taught me rf, so understand it can be done on ur own.Regarding langmuirs disease, this perhaps is the most important thing we all should keep in mind, when research turns to advocacy, its time to research something else. This for ur insight...and advancing beyond a forum nickname. Keep us on track and don't be afraid to plant some seeds of ur own.Thanks and back atcha for the energy you inject here. I hope to continue the ribbing about bendy pieces of wood you found on the floor for some time yet (just kidding). For quite some time I've thought, based on rough calculations, that a lot of this bleeding edge stuff is best served (i.e. best performance, etc.) at the nano-scale with metamaterials, MEMS, etc. There has been great progress of late in that regard (metamaterials research e.g. all beginning with Veselago's seminal paper in 1964) as can be seen from, for example, the progress in cloaking devices, which march on apace. This actually plays into the PV (Puthoff) and QV (White) space, and also into the Woodward space. Unfortunately, the amateur experimenter is SOL with such technology; it's still strictly under the provenance of well-funded research departments. Many orders of magnitude in performance improvement can be expected. Of course, the sceptic will tell you that a large number times zero is still not a lot Just wanted to throw that out there.
Another little thought experiment, aimed at those that think that, in deep space, an EmDrive produces thrust that is a function of its velocity relative to some absolute inertial reference frame in some way. We start off two identical EmDrives on parallel courses (far enough part to ignore any inter-drive forces to first order). We turn them both off at some particular speed, and they both coast in unison. While still turned off, we cause one of them to traverse a region of higher drag, and so of course it slows down relative to the other one. We then turn both batteries back on. Is it a reasonable demand to expect that both drives resume acceleration with different thrusts? Of course, it is not. Does their battery "know" their current speed? Of course, it does not. Although both batteries are emptied to the same extent, the speeds of the two drives are different! Now repeat the experiment, this time by booting one in the backside (say with a powerful laser) while both batteries are again off. Ask the same two questions after they both resume thrusting. The answers will be the same. There can be no dependency on speed for the thrust developed by the drive.Where does that leave us? With the potential for over-unity, of course! The value of k [N/W] is a fixed number descriptive of the EmDrive design; it is not a dynamical quantity. The acceleration will be constant as long as the battery lasts, or unless we feed back excess power to self-sustain this perpetual motion machine of the first kind. The drive obeys special relativity of course, and can never exceed light speed.It's not a pretty sight, but that's how the physics logically must be.
A design exercise: the design of an EmDrive spacecraft. The core idea is that the whole thing is propellantless, and therefore the craft will contain two types of EmDrive; one type being a set of rotary devices operating at overunity, and thus able to supply continuous free power to the second set of drive types, which fill the role of the main thrusters. Sadly we cannot exploit the overunity characteristics of the main drives, but on the other hand that might be seen as just plain greedy, since we already have free energy forever to accelerate the ship and to decelerate it too - all without propellant. Ad Astra indeed.
Quote from: deltaMass on 07/11/2015 05:40 amA design exercise: the design of an EmDrive spacecraft. The core idea is that the whole thing is propellantless, and therefore the craft will contain two types of EmDrive; one type being a set of rotary devices operating at overunity, and thus able to supply continuous free power to the second set of drive types, which fill the role of the main thrusters. Sadly we cannot exploit the overunity characteristics of the main drives, but on the other hand that might be seen as just plain greedy, since we already have free energy forever to accelerate the ship and to decelerate it too - all without propellant. Ad Astra indeed.The universe may just have a, untold as of yet, Gotcha Effect, that we will never experience until we try to go overunity.With a really good and careful build I may be able to get to 1.0N/kW with a high quality silver/gold internal layer and high precision frequency tracking system but that is then about the limit for non superconducting cavities.Would be really delighted to learn your thoughts on how to push that EMDrive into predicted overunity so we can see what happens???