Quote from: TheTraveller on 05/23/2015 03:48 pm...I refer to Feynman:"If it [theory] disagrees with experiment it is wrong."Yet the trust of this forum seems to be to reject Shawyer and Chinese theory, which matches their experimental results, and seek some new theory outside physics when all that is needed is to listen to Shawyer and the Chinese and apply existing theory in a non conventional way....Concerning Feynman, I was educated in the same institution where he studied, under the same scientific principles and approach. I performed experiments since I was a freshman (I was lucky that they had started the Undergrad Research Opportunity Program and immediately engaged in hybrid chemical rocket propulsion experiments) at that institution until I got my Ph.D. Nobody at that institution performs experiments following a single researcher's publications as if they were a holy book.Feynman's famous Lectures, and his professional life, teaches an approach to physical problems that is the diametrical opposite of following a single researcher as a Guru or a Prophet, whose publications have to be revered, obeyed and followed as a religious book. Concerning this thread its focus is on an objective, skeptical attitude trying to ascertain whether the experimental reports are an artifact or a real propulsion effect and if so whether they can be used for space applications, and also discussing those possible space propulsion applications.
...I refer to Feynman:"If it [theory] disagrees with experiment it is wrong."Yet the trust of this forum seems to be to reject Shawyer and Chinese theory, which matches their experimental results, and seek some new theory outside physics when all that is needed is to listen to Shawyer and the Chinese and apply existing theory in a non conventional way....
Brand new. Interview with the inventor of EmDrive. Good info in there.
No, EmDrive does not break Newton's Laws. In fact, it works because of Newton's Third Law. EmDrive produces thrust in one direction, and if it's allowed to, it will accelerate in the opposite direction. Momentum is conserved by this process. And that's what Newton's Third Law is looking for. In fact, EmDrive is based purely on classic physics -- the physics of Maxwell, Newton, and Einstein. There is really no need to bring in exotic physics to explain EmDrive. We don't need quantum vacuum plasma effects, and it is most certainly not a warp drive.
No, it is not reactionless. It is propellantless, or propellant-free perhaps, but in real life there is no such thing as a reactionless drive. Newton doesn't allow for it and I don't attempt to build one.
And there are also a growing number of university departments and private individuals who are trying to replicate our first experiments. This is of concern because an EmDrive is a potentially lethal device, particularly if you are close to measuring reasonable amounts of thrust it means you have a very high Q cavity, you are putting in significant amount of input power, and this makes it quite dangerous. So the way to handle the device is the way that I learnt in my early career as a defense contractor. You must devise rigorous, strict, and knowledgeable safety procedures before you start experimenting with EmDrive. It has the potential to kill you, and you must obviously bear this in mind. It's great fun, and it's very tempting to rush in and test it, but you must consider the safety aspects before you do this.
@TheTraveller: Come on. Just six little numbers is all I ask, to verify your claim that Shawyer's equations predict correctly the thrust value.Actually seven because #4 should be4. operating frequency and powerand two more if you really want to include curvature (although only one is necessary in order to deduce the second one)
I post again my paper where a proof is given that thrust could arise from space-time as shown from general relativity. I am preparing the version to post on arxiv and working through a numerical analysis of the final equation.
Quote from: deltaMass on 05/23/2015 06:11 pm@TheTraveller: Come on. Just six little numbers is all I ask, to verify your claim that Shawyer's equations predict correctly the thrust value.Actually seven because #4 should be4. operating frequency and powerand two more if you really want to include curvature (although only one is necessary in order to deduce the second one)It is Shawyer that claims his thrust equations correctly predict the thrust value.My goal is to be able to eventually do the same thing.When I have a spreadsheet that predicts the measured Flight Thruster thrust versus power input, from the guestimated dimensions, I'll post it for all to use.
Well, I'm in the following group:1: Shawyer's paper is completely confused. Right at the start he attributes the force to a greater radiation pressure upon the wide end, yet it pushes itself small end forward; this is based upon a completely confused discussion of reaction forces and thrust. This notion that there would be no force on the side walls "according to Maxwell's equations" is simply flat-out wrong. Maxwell's equations, as applied, yield zero thrust; the force on the side walls precisely balances out the pressure difference between the ends. (They're also Lorentz invariant so there's no special relativity corrections to be made)2: All explanations where the measured force is impacted upon the cavity walls by incident electromagnetic radiation are likewise wrong, whenever they involve speculations about the quantum vacuum or not. The measured force corresponds to the incident electromagnetic radiation deviating from conventional predictions by >50% (Shawyer, Chinese results), or >2.5% (EW results), which is in gross contradiction to experiments that measure electromagnetic radiation directly (many are precise to parts per billion or better).3: Regarding EW's experiments, their readings contradict each other (when flipped 180 degrees). Other experiments are substantially worse still, with high voltage wires, stiff waveguides being heated, etc. pushing the cavity mechanically. What results do you expect to get if there's no thrust but you got a bunch of high voltage wires, substantial heat, electrical current in the wires, and vibration? You can't seriously expect to get a literal zero.
If one has really technically penetrated a subject, things that previously seemed in complete contrast, might be purely mathematical transformations of each other
Quote from: StrongGR on 05/23/2015 05:56 pmI post again my paper where a proof is given that thrust could arise from space-time as shown from general relativity. I am preparing the version to post on arxiv and working through a numerical analysis of the final equation.I think eqn 60, the final expression for the thrust, would benefit from pulling out the common factors of the two terms. This makes it more readable and more understandable also.
Quote from: txdrive on 05/23/2015 06:26 pmWell, I'm in the following group:1: Shawyer's paper is completely confused. Right at the start he attributes the force to a greater radiation pressure upon the wide end, yet it pushes itself small end forward; this is based upon a completely confused discussion of reaction forces and thrust. This notion that there would be no force on the side walls "according to Maxwell's equations" is simply flat-out wrong. Maxwell's equations, as applied, yield zero thrust; the force on the side walls precisely balances out the pressure difference between the ends. (They're also Lorentz invariant so there's no special relativity corrections to be made)2: All explanations where the measured force is impacted upon the cavity walls by incident electromagnetic radiation are likewise wrong, whenever they involve speculations about the quantum vacuum or not. The measured force corresponds to the incident electromagnetic radiation deviating from conventional predictions by >50% (Shawyer, Chinese results), or >2.5% (EW results), which is in gross contradiction to experiments that measure electromagnetic radiation directly (many are precise to parts per billion or better).3: Regarding EW's experiments, their readings contradict each other (when flipped 180 degrees). Other experiments are substantially worse still, with high voltage wires, stiff waveguides being heated, etc. pushing the cavity mechanically. What results do you expect to get if there's no thrust but you got a bunch of high voltage wires, substantial heat, electrical current in the wires, and vibration? You can't seriously expect to get a literal zero.And you think the professional experimenters, not talking about the DIY versions here, haven't already considered this. You put forward an argument as if this was the first time anyone had thought of these issues. A greater part of the last thread was examining such issues amongst other things.
The scientific method is the exact opposite of staking a priori beliefs as expressed in polls.Scientists and engineers keep open minds while sifting and analyzing data according to the scientific method, and they reach a conclusion only after exhaustive independent replication of experiments.Quote from: John von NeumannIf one has really technically penetrated a subject, things that previously seemed in complete contrast, might be purely mathematical transformations of each other
(...)My pathway to replication is as follows:1) Create an Excel spreadsheet that models the 4 physical to thrust parameters as per Shawyer's equations and explanations and confirm thrust predictions against existing experimental data. Ok a BIG ask but doable.(....)8 ) Make thrust measurements using either a Teeter Totter balance beam or direct measurements sitting on a scale in Up, Down and Sideways orientation, inside a sealed box that is also a Faraday Cage as per the attachment.6 9) Publish the results.
I don't think many competent physicists have any interest in Shawyer's theories. What he's writing is so wrong it is painful to read. Experimental physics requires, at least, good knowledge of mechanics, and the glaring bit about the pressure puts anyone with such knowledge off.