Ah, kdhilliard, i think i might have stolen the quote you typed out. However, this is speculation.QuoteI'm pretty sure he is not saying that he has actually felt the thrust with his hand from any of his exiting drives, but instead that were you to build a model with higher thrust you could feel itFrom the video you could take it either way. Either he has, or you would, feel a force. What is odd though is how do you get from a reaction-less drive that operates by bouncing microwaves around in a cavity, to something that behaves more like a traditional rocket. How do you make that leap. Perhaps Shawyer found the rocket like behaviour when he built his prototype, has mashed the two together because he is not quite sure what is going on, and has been hand-waving ever since.
I'm pretty sure he is not saying that he has actually felt the thrust with his hand from any of his exiting drives, but instead that were you to build a model with higher thrust you could feel it
Added: As for the needed nonlinearity, it is the curving path of the radiation.
Quote from: aero on 05/24/2015 02:49 amAdded: As for the needed nonlinearity, it is the curving path of the radiation.I think that's probably the result of a non-linearity. But we have the differential heating of the end walls ?
Quote from: Notsosureofit on 05/24/2015 03:06 amQuote from: aero on 05/24/2015 02:49 amAdded: As for the needed nonlinearity, it is the curving path of the radiation.I think that's probably the result of a non-linearity. But we have the differential heating of the end walls ?Yes, I was thinking about that, and the heating pattern is clearly the same as the claimed mode, per Dr. Rodal's calculation and images. But recall that the thrust is very low in the analyzed case, meaning that the RF was turning only a small amount. So is the heating pattern exactly the same, or are the hot spots moved toward the edge by a small amount? The force on the big end would be something like BigEndForce = SmallEndForce * (1 - cos(incident angle))and if we assume a uniform rate of "turn" from the end of the dielectric to the big end, then the distance between the point of impact for a linear RF beam and a curving RF beam would be some integral of curve geometry that I don't have off the top of my head. This distance might or might not show on close examination of the thermal images and prediction theory. It's not likely to be obvious because ... well, just because.
Tossing Poynting vectors around begs the question of how sustained thrust at a level approximately Q times that of an equally-powered photon rocket could possibly obtain.
Quote from: deltaMass on 05/24/2015 02:53 amTossing Poynting vectors around begs the question of how sustained thrust at a level approximately Q times that of an equally-powered photon rocket could possibly obtain.You only have to prove it instantaneously. Then it will hold in the frame of reference of the cavity due to GR. Inertial frames won't do it, they aren't accelerating.
The other way to put it - we can actually set up a situation where radiation pressure upon the big end is greater than that upon the little end. In space, put a flashlight inside the cavity, pointed upon the big end (which is not perfectly reflective). The radiation pressure upon the big end will be greater than that upon the small end, and the cavity will accelerate big end forward. (The flashlight, if unsupported, will move in the opposite direction, like a photon rocket, but it could in principle be held in place, e.g. using magnetic levitation)
http://arxiv.org/abs/0912.1031v1Feigel says you can get thrust from the vacuum.http://science.slashdot.org/story/09/12/11/149220/How-To-Build-a-Quantum-Propulsion-Machinehttp://www.technologyreview.com/view/416614/a-blueprint-for-a-quantum-propulsion-machine/
Finally completed a simple UI.One thing to add is the ability to enter the small plate diameter - and switch between small plate diameter or design factor and have the other parameter computed and displayed.Also a toggle for a small end cylinder. Now to start messing with modes.I prefer this better than a spreadsheet. I wrote an Excel like spreadsheet years ago and even with the knowledge I have about them find them constricting.
Two errors there. First, momentum is conserved at all times in all sensible reference frames for a system comprising a photon bouncing between two mirrors. There is no "borrowing from The Cosmic Badger" going on. Secondly, please don't try and use "the reference frame of a photon", accelerated or otherwise. It's a semantic null statement to put things in that frame of reference. It's also another of Shawyer's conceptual errors.
...In a ferroelectric magnet there are domains where electrons have their spins aligned in a particular direction to create a stable magnetic field. The spin of the electron is in its quantum ground state, and spin is intrinsically an interaction between the electron and the QV. If the random spin-flips of electrons can be detected in either direction, then that is extracting energy from the QV. Likewise, the electromagnetic ZPF is simply the 0 Temperature limit of Planck's blackbody temperature spectrum. If the temperature environment of the magnet is increased, the probability of spin-flips to a higher energy state becomes more likely. The symmetry is broken and can be detected as -dB/dt = curl(E). This can be used to extract electrical energy from the thermal input.Todd
Quote from: deltaMass on 05/24/2015 04:59 amTwo errors there. First, momentum is conserved at all times in all sensible reference frames for a system comprising a photon bouncing between two mirrors. There is no "borrowing from The Cosmic Badger" going on. Secondly, please don't try and use "the reference frame of a photon", accelerated or otherwise. It's a semantic null statement to put things in that frame of reference. It's also another of Shawyer's conceptual errors.Just to be clear about errors. Do you believe that Shawyer and the Chinese have made errors in measured thrust in their test devices and there is really no thrust?
I can understand your curiosity about what all the other pollsters believe, when you yourself are the sole occupant of one of the offered categories.