cute program for designing a helical quadfire antenna or as called a eggbeater.http://jcoppens.com/ant/qfh/calc.en.php
Quote from: Bob012345 on 11/11/2016 06:16 pmBecause that's how they rationalize the EmDrive can't work at all. I don't know anyone who thinks it does work that argues CoM is not applicable.Here is how I see it:Fact: a seemingly anomalous thrust is being observed in experiments. No obvious exhaust is detected. The device seems to be gaining momentum.Explanation #1: this is the result of a systematic error or some spurious force that has not been taken into account yet. If true, EmDrive cannot work. This can be confirmed or ruled out by doing further experiments (in space, etc).Explanation #2: the thrust is real, but it is caused by interaction with some object/field (hopefully not just the Earth). This interaction may require a new physical theory to be developed, but this theory would not overturn CoM. If true, this would mean that the object(s) it's interacting with acts as a propellant, and as the relative "device/propellant" velocity increases, the acceleration rate will drop (otherwise CoM/CoE would not be observed, as has been previously discussed many times in this thread). This does not mean that EmDrive cannot work, it just means that there are some limitations to the thrust it can deliver, as dictated by CoM/CoE.Explanation #3: the thrust is real, there is no interaction with external fields/objects, CoM/CoE is not observed in the classical sense and must be corrected. If true, the device could potentially deliver constant acceleration for constant power regardless of its relative movement (since it's not interacting with any external fields/objects).All I'm saying is that even if further experiments show that #1 does not explain the thrust, then #2 is much more likely than #3, because #3 implies free energy or perpetual motion.
Because that's how they rationalize the EmDrive can't work at all. I don't know anyone who thinks it does work that argues CoM is not applicable.
Quote from: wicoe on 11/11/2016 07:08 pmQuote from: Bob012345 on 11/11/2016 06:55 pmOh joy, here we go again!My thoughts exactly! And yet if you take the system "device + objects it's pushing against" and write the CoE/CoM equations, it becomes obvious that as the relative velocity increases, the same acceleration (dV over dT) would require more energy. I'm not sure why this may not be obvious to some people, but writing down the simple newtonian equations usually helps. If there is another hypothetical way to write these equations without requiring dE (required energy to accelerate by dV) to grow with V, please provide an example.One example where it doesn't is this. Imagine a uniform expansive gravitational field that our ship was falling through. Assume that field was of infinite extent. Our ship would maintain its acceleration indefinitely. The means it imparts energy is based on distance covered (work) not speed or time. Perhaps the EmDrive create such a local field that it falls through. CoM and CoE are always conserved for all situations and observers.
Quote from: Bob012345 on 11/11/2016 06:55 pmOh joy, here we go again!My thoughts exactly! And yet if you take the system "device + objects it's pushing against" and write the CoE/CoM equations, it becomes obvious that as the relative velocity increases, the same acceleration (dV over dT) would require more energy. I'm not sure why this may not be obvious to some people, but writing down the simple newtonian equations usually helps. If there is another hypothetical way to write these equations without requiring dE (required energy to accelerate by dV) to grow with V, please provide an example.
Oh joy, here we go again!
Maybe someone ought to try a double helix antenna design. Nature sure likes it for chemical manipulation.
Quote from: Bob Woods on 11/12/2016 05:44 amMaybe someone ought to try a double helix antenna design. Nature sure likes it for chemical manipulation.Yes, but how does it behaves when used as a radiator inside a cavity? All publications and calculations I have seen are in free space. Anybody wants to do simulations?Peter
Decided to finally register after having followed along for the last about 90 pages.Noticing a few people wondering why #3 is so unlikely. Aside from free energy/perpetual motion issues, which are significant by themself. Any drive that can produce constant acceleration for constant input power, regardless of relative movement, must be inherently an FTL capable drive, since it would not be constrained by the speed of light given sufficient time to accelerate. Even an Alcubierre drive seems like it wouldn't achieve constant acceleration for constant input power. It seems like there's slim evidence that the drive is acting as a warp/Alcubierre drive, and thus seems little reason to state that it would be.Although, I do wonder a bit about what the principles of COE and COM have to say if it's not the drive itself that is moving (or being affected by it), but the space around it (not that I'm expecting that to be the case). Again, not saying it is the case, but seems like the "push-pull" actions of EMdrive bear some similarities to those that might be expected by an Alcubierre style drive. Though seems like there's pretty much nil evidence to say it is, at least that's been confirmed. Seems like this could be tested by placing some accelerometers very close to, but not touching, the drive and see if there any effect. (I wouldn't consider this paragraph as speculation, but rather simple theoretical musings)
Quantum mechanics tells us that when the copper atoms and bulk metal absorb momentum from the field, It feels a recoil in the direction of the momentum vector to satisfy CoM. When it re-emitts the momentum, it does not necessarily have to have the "equal and opposite" value! The recoil of the atom is opposite the momentum of the emitted photon. It's direction and momentum is a probability distribution, partly determined by the motion of the atoms (heat).
Take a solar sail and its simplified model: an incoming photon is either absorbed or reflected by the sail: - When the photon is absorbed, its momentum p is transmitted forward to the atom in the same direction as the incoming photon, and has the same momentum vector p. The sail moves forward.- When the photon is reflected backwards, the photon carries a backward momentum -p and imparts a forward momentum 2p to the atom of the sail. The sail moves forward.Now, let's take a closed tapered cavity, and what Shawyer says. I know Shawyer's theory beaks CoM and CoE and that the cavity as a whole can't move as a closed system. But let this aside for the moment and let's focus only on photon momentum description. Shawyer says the incoming photon momentum on the big end is greater than the incoming photon momentum on the small end, because the photon wavelength would vary according to the guide wavelength, which continuously varies in a tapered cavity. The guide wavelength is greater at the big end, so the group velocity, so the momentum. Shawyer says the resulting radiation pressure on the big end Fbig is greater than the radiation pressure on the small end Fsmall. He calls the resulting force Fbig-Fsmall the backward static force or "thrust force". Please note that according to Shawyer, the frustum moves forward in the opposite direction to this thrust force, small end leading, along a "reaction force" vector:But let this claim aside for now as it is counterintuitive, to say the least.Shawyer only talks about the momentum imparted to the atoms of the end plates, and then posits an equal and opposite force arises (the reaction force) which is necessarily there to counterbalance the static thrust force, in order to satisfy CoM. Yet, while he has built all the needed tools, Shawyer doesn't consider the action of the inertial mass of the reflected photons themselves, which are still part of the system enclosed by the cavity (as opposed to the free space photons incoming on our out of a solar sail, which make the solar sail an open system). So about the momentum carried by photons between the end plates, which would vary continuously between reflections at the ends, while they are travelling: - The photon momentum would continuously decrease while travelling from big end to small end.- The photon momentum would continuously increase while travelling from small end to big end.Shawyer is continuously bashed for his "theory". But this is exactly what McCulloch describes with MiHsC:"Fewer Unruh waves will fit at the small end of the frustum, resulting in a pressure differential. Photons at the larger end therefore have higher inertial mass, and to conserve momentum in our reference frame, its frame, the cavity, must move towards the narrow end."Also:"MiHsC allows more Unruh waves (greater photon inertial mass) at the wide end, so as new microwave energy is put into the cavity its centre of mass is continually being shifted by MiHsC towards the wide end (see diagram). To conserve momentum the cavity has to move the other way towards the narrow end."So Shawyer is focusing on the momentum imparted to the solid atoms of the frustum, and posits an equal and opposite reaction force.While McCulloch is focusing on the photon momentum gradually shifting while travelling between the two end plates. Wouldn't this be a start to finally consider separately Shawyer's backward "thrust force component" and Shawyer's forward "reaction force component", the latter being in fact McCulloch's force?I have the feeling that Shawyer's backward thrust force can't indeed move the frustum, as it seems like "moving a car pushing on a steering wheel while being sat in the driver's seat, while someone sat in the back seats is pushing even harder on the rear windscreen." But I have also the feeling that a gradually shifting photon inertial mass in one direction would move the frustum in the other direction, like a long boat would move forward on the water as a reaction when a sailor on the deck carries a big weight stored at the bow, running with it towards the stern. While the weight dropped on the deck at the stern would slowly evaporate (power dissipation) the sailor would return without it (lighter, only sailor's mass) at the bow to reiterate the process with another weight. This illustrate the displacement of an object as a reaction to the continuous shifting of its center of mass, and the process keeps working as long as there are weights stored onboard and a sailor to displace them (i.e. as long as RF power is supplied into the tuned resonant cavity).This seems similar to the concept of continuous EM energy center of mass displacement with continuous RF power feeding and continuous power loss described differently by WarpTech.
Quote from: Bob012345 on 11/11/2016 07:32 pmQuote from: wicoe on 11/11/2016 07:08 pmQuote from: Bob012345 on 11/11/2016 06:55 pmOh joy, here we go again!My thoughts exactly! And yet if you take the system "device + objects it's pushing against" and write the CoE/CoM equations, it becomes obvious that as the relative velocity increases, the same acceleration (dV over dT) would require more energy. I'm not sure why this may not be obvious to some people, but writing down the simple newtonian equations usually helps. If there is another hypothetical way to write these equations without requiring dE (required energy to accelerate by dV) to grow with V, please provide an example.One example where it doesn't is this. Imagine a uniform expansive gravitational field that our ship was falling through. Assume that field was of infinite extent. Our ship would maintain its acceleration indefinitely. The means it imparts energy is based on distance covered (work) not speed or time. Perhaps the EmDrive create such a local field that it falls through. CoM and CoE are always conserved for all situations and observers.P = F * v. As the velocity increases, the power (rate of energy added to the object) also increases, so it is constant force, but not constant power. As you say, energy comes from distance covered, and since it covers more distance per time as it is moving faster it also gets more kinetic energy per time (converted from potential energy) as its velocity increases.Yet again, your "example" of constant force/power is not one. Please work these through yourself a little more carefully before posting.
Quote from: WarpTech on 11/11/2016 07:41 pmQuantum mechanics tells us that when the copper atoms and bulk metal absorb momentum from the field, It feels a recoil in the direction of the momentum vector to satisfy CoM. When it re-emitts the momentum, it does not necessarily have to have the "equal and opposite" value! The recoil of the atom is opposite the momentum of the emitted photon. It's direction and momentum is a probability distribution, partly determined by the motion of the atoms (heat)....But I have also the feeling that a gradually shifting photon inertial mass in one direction would move the frustum in the other direction, like a long boat would move forward on the water as a reaction when a sailor on the deck carries a big weight stored at the bow, running with it towards the stern. While the weight dropped on the deck at the stern would slowly evaporate (power dissipation) the sailor would return without it (lighter, only sailor's mass) at the bow to reiterate the process with another weight. This illustrate the displacement of an object as a reaction to the continuous shifting of its center of mass, and the process keeps working as long as there are weights stored onboard and a sailor to displace them (i.e. as long as RF power is supplied into the tuned resonant cavity).This seems similar to the concept of continuous EM energy center of mass displacement with continuous RF power feeding and continuous power loss described differently by WarpTech.
Quote from: meberbs on 11/11/2016 10:32 pmQuote from: Bob012345 on 11/11/2016 07:32 pmQuote from: wicoe on 11/11/2016 07:08 pmQuote from: Bob012345 on 11/11/2016 06:55 pmOh joy, here we go again!My thoughts exactly! And yet if you take the system "device + objects it's pushing against" and write the CoE/CoM equations, it becomes obvious that as the relative velocity increases, the same acceleration (dV over dT) would require more energy. I'm not sure why this may not be obvious to some people, but writing down the simple newtonian equations usually helps. If there is another hypothetical way to write these equations without requiring dE (required energy to accelerate by dV) to grow with V, please provide an example.One example where it doesn't is this. Imagine a uniform expansive gravitational field that our ship was falling through. Assume that field was of infinite extent. Our ship would maintain its acceleration indefinitely. The means it imparts energy is based on distance covered (work) not speed or time. Perhaps the EmDrive create such a local field that it falls through. CoM and CoE are always conserved for all situations and observers.P = F * v. As the velocity increases, the power (rate of energy added to the object) also increases, so it is constant force, but not constant power. As you say, energy comes from distance covered, and since it covers more distance per time as it is moving faster it also gets more kinetic energy per time (converted from potential energy) as its velocity increases.Yet again, your "example" of constant force/power is not one. Please work these through yourself a little more carefully before posting.As I stated many times before, P=F*v is the mechanical power the system has and is not to be confused with the input electrical power we were discussing in earlier discussions. In this discussion, I was not discussing anything about input electrical power to an EmDrive. Of course even if the EmDrive electrical power was constant for a constant acceleration, the mechanical power would be velocity dependent and thus observer dependent. My question to you is this, two different observers at different velocities see different powers of the ship. Which is the real power?
...The big difference between Shawyer and McCulloch, is that fact that Shawyer claims that it works with standard physics, when McCulloch has a new theory, new physics.With standard physics, there is not way it can works. Shawyer affirms that there is no pressure on the side walls. With standard physics it is false.At the opposite, With MiHsC, there is a minimal acceleration law that allows the force to be different. So, if photons are accelerating in an asymetrical way when bouncing, you can have asymetrical forces, and a thrust in some direction. This thrust means an interaction with the rest of the universe.That is the point that I didn't understood in MiHsC. How the energy stolen by an Emdrive translate in the rest of the universe ?For example, when a probe steal energy by a gravity assist, the planet concerned is loosing a bit of speed around the sun. We can calculate the exact modification of the trajectory (even if it is not mesurable)With MiHsC, I don't have a global understanding of the theory, and I don't know what happen to the rest of the universe. But what I understood is that there is an interaction, and the Emdrive is not anymore an isolated system. That is the big difference with Shawyer explanations involving only standard physics.If anybody has a better understanding of MiHsC, it would be welcome.
The big difference between Shawyer and McCulloch, is that fact that Shawyer claims that it works with standard physics, when McCulloch has a new theory, new physics.
With standard physics, there is not way it can works. Shawyer affirms that there is no pressure on the side walls. With standard physics it is false.
Quote from: Gilbertdrive on 11/12/2016 03:45 pmThe big difference between Shawyer and McCulloch, is that fact that Shawyer claims that it works with standard physics, when McCulloch has a new theory, new physics.But both come to the same conclusion: the photons loose inertial mass while travelling from the big end towards the small end in a tapered cavity, and gain inertial mass while travelling small to big.McCulloch says this is caused by the Unruh waves difference between big and small ends, that changes photon momentum between the end plates. This is new physics indeed.Shawyer says it is the guide wavelength variation that changes photon momentum due to the Doppler effect: photons going small towards big end decrease in frequency (redshift) and photons going big to small increase in frequency (blueshift) and has a consequence their inertial mass varies accordingly.I try to understand what makes Shawyer's statement impossible. What is needed first is answering this couple of questions:- In a converging waveguide, does the frequency of the travelling wave increase?- In a diverging waveguide, does the frequency of the travelling wave decrease?Or even simpler, this unique question: Does the wavelength of an EM wave depend on the guide wavelength?...
...I try to understand what makes Shawyer's statement impossible. What is needed first is answering this couple of questions:- In a converging waveguide, does the frequency of the travelling wave increase?- In a diverging waveguide, does the frequency of the travelling wave decrease?Or even simpler, this unique question: Does the wavelength of an EM wave depend on the guide wavelength?We know TheTraveller's explanation. But what do physicists have to say about this. Have experiments been conducted measuring real radiation pressures on both end plates of cylindrical or tapered closed resonant cavities, or measuring local effective frequency of EM waves into various straight open waveguides of various diameters, or along z-axis of a tapered waveguide?...
It can be done with standard physics if you include asymmetrical damping and losses.Regarding MiHsC. As I understand it. Inside the empty cavity, before you apply any RF input, there is already an EM Zero Point Field (ZPF) This field is not symmetrical due to the asymmetry of the cavity. Just as in the Casimir effect, the modes which are allowed inside the cavity are not symmetrical due to the taper, resulting in a gradient in the available power of the ZPF. This gradient in the available power defines a non-inertial reference frame. An inertial frame being defined as one where; the power absorbed = power radiated by a test particle in the ZPF, is symmetrical. All forces sum to 0.
Quote from: Bob012345 on 11/12/2016 04:51 pmQuote from: meberbs on 11/11/2016 10:32 pmQuote from: Bob012345 on 11/11/2016 07:32 pmQuote from: wicoe on 11/11/2016 07:08 pmQuote from: Bob012345 on 11/11/2016 06:55 pmOh joy, here we go again!My thoughts exactly! And yet if you take the system "device + objects it's pushing against" and write the CoE/CoM equations, it becomes obvious that as the relative velocity increases, the same acceleration (dV over dT) would require more energy. I'm not sure why this may not be obvious to some people, but writing down the simple newtonian equations usually helps. If there is another hypothetical way to write these equations without requiring dE (required energy to accelerate by dV) to grow with V, please provide an example.One example where it doesn't is this. Imagine a uniform expansive gravitational field that our ship was falling through. Assume that field was of infinite extent. Our ship would maintain its acceleration indefinitely. The means it imparts energy is based on distance covered (work) not speed or time. Perhaps the EmDrive create such a local field that it falls through. CoM and CoE are always conserved for all situations and observers.P = F * v. As the velocity increases, the power (rate of energy added to the object) also increases, so it is constant force, but not constant power. As you say, energy comes from distance covered, and since it covers more distance per time as it is moving faster it also gets more kinetic energy per time (converted from potential energy) as its velocity increases.Yet again, your "example" of constant force/power is not one. Please work these through yourself a little more carefully before posting.As I stated many times before, P=F*v is the mechanical power the system has and is not to be confused with the input electrical power we were discussing in earlier discussions. In this discussion, I was not discussing anything about input electrical power to an EmDrive. Of course even if the EmDrive electrical power was constant for a constant acceleration, the mechanical power would be velocity dependent and thus observer dependent. My question to you is this, two different observers at different velocities see different powers of the ship. Which is the real power?CoE means that, if the system is not stealing energy to something else, the electrical power has to be inferior or equal to the mechanical power.For P=F*V it is clear, this relation is not true in all referential. This relation is true in the referential linked to what you are pushing against. That is why a car is limited (best possible case) to F=Electrical Power/V in the referential of the road. From the viewpoint of an observer on mars, F can be superior to P/V, because, from the viewpoint of a martian, the car can steal energy to the earth. For each reference frame, mars or earth, CoE is verified, but the relation F=P/V is not true for any referential.It is important to note that the fact of stealing energy depends on the reference frame. From the earth reference frame, a probe that make an earth gravity assist has stolen nothing. From a sun reference frame, the probe has stolen Kinetic Energy to the earth.
I previously said I think there is energy stealing happening. I just don't know how yet. But my example works so the only question is how much power would it take to create such a local field. If it depends on speed, in reference to what? A device floating in deep space doesn't know what speed it's moving at.
Quote from: WarpTech on 11/12/2016 05:21 pmIt can be done with standard physics if you include asymmetrical damping and losses.Regarding MiHsC. As I understand it. Inside the empty cavity, before you apply any RF input, there is already an EM Zero Point Field (ZPF) This field is not symmetrical due to the asymmetry of the cavity. Just as in the Casimir effect, the modes which are allowed inside the cavity are not symmetrical due to the taper, resulting in a gradient in the available power of the ZPF. This gradient in the available power defines a non-inertial reference frame. An inertial frame being defined as one where; the power absorbed = power radiated by a test particle in the ZPF, is symmetrical. All forces sum to 0.I disagree. With standard physics, Asymetrical damping and losses in the frustrum considered as a closed system can't give him more momentum than a perfect collimated photon rocket would do. Standard physics complies with CoM, and this clearly violates CoM when you consider the entire device (and not only try to look at the photons inside)If you could get this result using correctly standard physics formulas, it would means that standard physics are inconsistent, and that we can demonstrate using standard physics laws that 1=2.Thanks very much for the explanation about MiHsC.
