Taking a shot at an "axion condensate dark matter" energy to force calculation.So theory and experiment both give a reduction in "sound speed" in a dilute condensate of ~ 10^-6. So, let's say s = < 300 m/sec, given the assumption that the "axions" "interact" via gravity at c.
Using a rough experimental result of 10W => 50 micronewtons for comparison.At 300 m/sec, I need to generate 2.5 X 10^22 phonons/sec at a power of 1.5 X 10-2 watts to generate that 50 micronewtons.So 15 milliwatts out of 10 watts => 0.15% (pretty high)Edit +10^22 and phonons not photons
Quote from: Notsosureofit on 10/06/2014 04:24 pmTaking a shot at an "axion condensate dark matter" energy to force calculation.So theory and experiment both give a reduction in "sound speed" in a dilute condensate of ~ 10^-6. So, let's say s = < 300 m/sec, given the assumption that the "axions" "interact" via gravity at c.Where does it come from this 10^-6 ? specific to Bose Einstein condensates ? Reduction relative to what, the speed of "interactions" (sound ?) without BE condensation ?QuoteUsing a rough experimental result of 10W => 50 micronewtons for comparison.At 300 m/sec, I need to generate 2.5 X 10^22 phonons/sec at a power of 1.5 X 10-2 watts to generate that 50 micronewtons.So 15 milliwatts out of 10 watts => 0.15% (pretty high)Edit +10^22 and phonons not photonsI don't get it, where 2.5e22 comes from ?Trying to understand the equivalent mass of the quanta you are pushing onto 50e-6 = 300 * mass_1_phonon*2.5e22kg*m/sē = m/s * kg / s => mass_1_phonon = 50e-6 / (300*2.5e22) = 6.7e-30 kg = 3.7MeV why ?2.5e22 * 6.7e-30 = 1.7e-7 kg/s ( We didn't need to go through the individual phonon mass, it is just 50e-6/300 as mass_flow=force/speed)Power of a jet having mass at sending mass from its own speed is 0.5*mass_flow*speedē = 0.5*1.7e-7*300ē = 7.5e-3 WLost a .5 factor here, but looks like I'm on the right track. You are like pushing on something at a relative speed of 300m/s : pow = force * speed = 1.5e-2 and considering there is no recoil of the medium because it's a "rigid" condensate ? But however rigid it would be, it would still need to have a certain mass : imagine an infinitly rigid slab spanning the solar system but weighing a gram, you couldn't really grab onto it to push efficiently a ship of one ton, unless sending the slab very very fast in the opposite direction. So you have to "recruit" a mass to push onto at those efficiencies (that is, at this low characteristic speed) and this mass is on the order of 1.7e-7 kg each second. If I recall well, absolute experimentally checked upper bound (not likely) to DM density at earth orbit is about 1E6 GeV /cm^3 = 1.8e-24 kg/m^3 So the mass of DM to be pushed onto must be found on the order of 1e17 m^3, roughly 300km radius sphere.How is it possible to recruit in 1s the mass of medium to be found in such a volume when the speed of sound in said medium is 300m/s ?There is simply not enough naturally occurring DM density to be of practical use, this is from the known gravitational bounds to density, so nothing more to be exploited could hide (in some specific kind of dark matter...)I know the discussion drifted to other considerations long time ago but I had to destroy that (sorry Notsosureofit, nothing personal, just to close all doors to classical natural DM)Now I will be attacking Shawyer's derivations.
Following extensive review, no contravention of the laws of the conservation of momentum and conservation of energy has been identified.
.../...On the other hand, White's approach supposedly predicts thrust from a Shawyer EmDrive, while Woodward's does not. It is generally acknowledged that Shawyer's explanation of his invention makes no sense, but that doesn't necessarily mean the invention itself doesn't work. IIRC multiple parties have reported thrust from EmDrives, and not all of them are in China...
.../...Most physicists are clueless when it comes to engineering, especially anyone who isn't in experiment. They simply lack the design skills to compete with engineers. Conversely, when an engineer tries to do physics, you often end up with a Roger Shawyer.
Quote from: Mulletron on 10/08/2014 08:09 pmQuote"Superconductivity: a quantum mechanics effect for which people's intuition fails, because our intuition is built around our macro world and not the quantum world. One would have to work out the quantum mechanics math to answer."This is a hasty generalization.
Quote"Superconductivity: a quantum mechanics effect for which people's intuition fails, because our intuition is built around our macro world and not the quantum world. One would have to work out the quantum mechanics math to answer."This is a hasty generalization.
"Superconductivity: a quantum mechanics effect for which people's intuition fails, because our intuition is built around our macro world and not the quantum world. One would have to work out the quantum mechanics math to answer."
Quote from: IslandPlaya on 10/08/2014 07:51 pm...I will try to embiggen my knowledge further.Embiggen ?
...I will try to embiggen my knowledge further.
A follow up to JohnFornaro's questions:1) Q: ""Do objects undergoing NO acceleration have inertial mass? NO"...Therefore, I take issue with the above statement. We still don't know what the "true" orgigin of inertia is."A: You are right, we don't know the true origin of inertia. Lots of people have ideas. I have one too. It is time.2a) Q: "Now, if one law of the universe can be broken, then all laws of the universe can be broken."A: How do you figure? We're not breaking any laws here. But if we were, why the slippery slope?2b) Q: "If a "new universe" is being created inside a copper can, which, tho not shielded from gravity, is subject to all other universal laws, two questions occur. How can it be called a "new universe" if subject to the inertial laws of this one?"A: If you change any single property of a consistent universe, is it still the same universe? Or a different universe? I say a different one. Because it has different rules. A universe is defined by its rules.3) Q: "Is the 45 degree angled copper can the only way this assymetrical acceleration can occur?"A: NO, read McCulloch's paper on inertia.
I guess its time for my 10^7 contribution.I've attached a current estimate of dark matter in the solar system, and for convenience converted 16.5E16 kg / AU^3 to 4.5E-17 kg/m^3. That is quite a lot more than your number, 1.8e-24 kg/m^3 . In fact, it is almost exactly the value needed.I do note that a drive based on this physics won't be so good much beyond Saturn. The DM mass really tails off with distance from the sun.
Quote from: aero on 10/09/2014 12:52 amI guess its time for my 10^7 contribution.I've attached a current estimate of dark matter in the solar system, and for convenience converted 16.5E16 kg / AU^3 to 4.5E-17 kg/m^3. That is quite a lot more than your number...Yeah, I just, you know, forgot the G in GeV. Off by 9 orders of magnitude. Post corrected. Many thanks for not making myself a fool for too long. ... This is weakly interacting after all. Please detect DM before pushing too much on it.
I guess its time for my 10^7 contribution.I've attached a current estimate of dark matter in the solar system, and for convenience converted 16.5E16 kg / AU^3 to 4.5E-17 kg/m^3. That is quite a lot more than your number...
Quote from: frobnicat on 10/09/2014 01:25 amQuote from: aero on 10/09/2014 12:52 amI guess its time for my 10^7 contribution.I've attached a current estimate of dark matter in the solar system, and for convenience converted 16.5E16 kg / AU^3 to 4.5E-17 kg/m^3. That is quite a lot more than your number...Yeah, I just, you know, forgot the G in GeV. Off by 9 orders of magnitude. Post corrected. Many thanks for not making myself a fool for too long. ... This is weakly interacting after all. Please detect DM before pushing too much on it.I was wondering about all the strike thrus. Just go ahead and edit it so it reads better. Add a "mea culpa" at the end. I'm not gonna ask for an apoligy, 'cause I drop zeros all the time.It's true tho, that you can't push very hard on something that is so rare. But then I got confused. You're not talking about "DM fusion", right?Ai chihuahua.
Quote from: Mulletron on 10/08/2014 11:08 pmA follow up to JohnFornaro's questions:1) Q: ""Do objects undergoing NO acceleration have inertial mass? NO"...Therefore, I take issue with the above statement. We still don't know what the "true" orgigin of inertia is."A: You are right, we don't know the true origin of inertia. Lots of people have ideas. I have one too. It is time.2a) Q: "Now, if one law of the universe can be broken, then all laws of the universe can be broken."A: How do you figure? We're not breaking any laws here. But if we were, why the slippery slope?2b) Q: "If a "new universe" is being created inside a copper can, which, tho not shielded from gravity, is subject to all other universal laws, two questions occur. How can it be called a "new universe" if subject to the inertial laws of this one?"A: If you change any single property of a consistent universe, is it still the same universe? Or a different universe? I say a different one. Because it has different rules. A universe is defined by its rules.3) Q: "Is the 45 degree angled copper can the only way this assymetrical acceleration can occur?"A: NO, read McCulloch's paper on inertia.1) Thanks for the engagement. Again, an object or particle with no acceleration has yet to be found. Even at lo, lo, how lo can you go speeds, a massive object has inertia equal to its mass. My objection was that we do not know, and have no evidence that inertia disappears with no acceleration.My sense is, that you (well, one) can't go wrong by assuming that inertia exists in all frames of reference.2a&b) You answered "a" with "b". You say it's a different universe, and maybe we're struggling with semantics here. But then you go on to suggest that a "property" in the "new" universe is being changed. We're not talking about the color of paint as a property, we're talking about fundamental properties, which in theory, we cannot change.Whatever is happening in the copper can obeys the laws of the universe that it is embedded in. No matter how much you embiggen it.3) Dang. I knew you were going to say that. Will try and find the time to throw an eyeball over it. You all must be able to read at least an order of magnitute faster than I can, and I read so fast that my lips can't keep up.4) What about Bohm's "implicate order". Do you think it has bearing on this EM-drive and related physics?
Quote from: aero on 10/09/2014 12:52 amI guess its time for my 10^7 contribution.I've attached a current estimate of dark matter in the solar system, and for convenience converted 16.5E16 kg / AU^3 to 4.5E-17 kg/m^3. That is quite a lot more than your number, 1.8e-24 kg/m^3 . In fact, it is almost exactly the value needed.I do note that a drive based on this physics won't be so good much beyond Saturn. The DM mass really tails off with distance from the sun.Yeah, I just, you know, forgot the G in GeV. Off by 9 orders of magnitude. Post corrected. Many thanks for not making myself a fool for too long.I took a looser upper bound because I thought we would be so far from reaching the necessary mass. You numbers above background galactic DM are more precise (proven ? probable ? possible ? speculative ?). This doesn't tell where this 300m/s from Notsosureofit comes from...Also, how could you meet DM at such low speed for a long time ? The equation for power of pushing on a medium is dependant on the speed you have in the medium, not the speed of sound of the medium. Unless there is a lump of cold DM orbiting with the earth we would encounter DM at a few km/s even on the ground. This is weakly interacting after all. Please detect DM before pushing too much on it.
Quote from: aero on 10/07/2014 03:56 pmQuestion - Is there any way to know the shapes of the standing waves within the cavity, with and without the resonator?See here for a curved truncated cone: http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.htmlfor the cavity itself (not the dielectric resonator)Observe that the ends, however are not flat in this solution for 1/r not equal to zero. Shawyer's and NASA truncated cone have flat ends with 1/r = 0 (r-> Infinity at ends)
Question - Is there any way to know the shapes of the standing waves within the cavity, with and without the resonator?
...Can anyone explain why it would move?...
Quote from: Mulletron on 10/09/2014 03:15 am...Can anyone explain why it would move?...McCulloch stated << the microwaves bouncing around within the cavity have inertial mass (em radiation does: that's why it can push a Solar sail) and their inertia is determined by MiHsC (quantised inertia). In MiHsC the Unruh waves are allowed only if they fit exactly within the Hubble horizon or within a local Rindler horizon, .. if the cavity wall in this case was acting like a horizon... then the microwaves at the wide end would have more inertia than those at the narrow end since more Unruh waves would fit.as a microwave beam goes from the narrow end to the wide end it gains inertial mass. Now I can try something I've used before (for the Tajmar effect [see http://arxiv.org/abs/1106.3266 ]) and say, in order to still conserve momentum (mass*velocity) for the whole system, if mass goes up then velocity must go down, and the only way to achieve that is to have the whole structure move towards the narrow end.>>
Quote from: Rodal on 10/09/2014 01:06 pmQuote from: Mulletron on 10/09/2014 03:15 am...Can anyone explain why it would move?...McCulloch stated << the microwaves bouncing around within the cavity have inertial mass (em radiation does: that's why it can push a Solar sail) and their inertia is determined by MiHsC (quantised inertia). In MiHsC the Unruh waves are allowed only if they fit exactly within the Hubble horizon or within a local Rindler horizon, .. if the cavity wall in this case was acting like a horizon... then the microwaves at the wide end would have more inertia than those at the narrow end since more Unruh waves would fit.as a microwave beam goes from the narrow end to the wide end it gains inertial mass. Now I can try something I've used before (for the Tajmar effect [see http://arxiv.org/abs/1106.3266 ]) and say, in order to still conserve momentum (mass*velocity) for the whole system, if mass goes up then velocity must go down, and the only way to achieve that is to have the whole structure move towards the narrow end.>>I know he says that. I just modeled that (what he said) in my most recent huge post and it failed. He maintained himself it is a leap. I tried to push the "I believe button" and it still didn't work. This thing doesn't expel any reaction mass. So now I'm back in line with Dr. White. The question is how?
Quote from: Mulletron on 10/09/2014 01:17 pmQuote from: Rodal on 10/09/2014 01:06 pmQuote from: Mulletron on 10/09/2014 03:15 am...Can anyone explain why it would move?...McCulloch stated << the microwaves bouncing around within the cavity have inertial mass (em radiation does: that's why it can push a Solar sail) and their inertia is determined by MiHsC (quantised inertia). In MiHsC the Unruh waves are allowed only if they fit exactly within the Hubble horizon or within a local Rindler horizon, .. if the cavity wall in this case was acting like a horizon... then the microwaves at the wide end would have more inertia than those at the narrow end since more Unruh waves would fit.as a microwave beam goes from the narrow end to the wide end it gains inertial mass. Now I can try something I've used before (for the Tajmar effect [see http://arxiv.org/abs/1106.3266 ]) and say, in order to still conserve momentum (mass*velocity) for the whole system, if mass goes up then velocity must go down, and the only way to achieve that is to have the whole structure move towards the narrow end.>>I know he says that. I just modeled that (what he said) in my most recent huge post and it failed. He maintained himself it is a leap. I tried to push the "I believe button" and it still didn't work. This thing doesn't expel any reaction mass. So now I'm back in line with Dr. White. The question is how?Can you explain in as few words as possible, what alternative explanation you have for conserving momentum (instead of McCulloch's proposal to have a force pushing the whole systemtowards the narrow end) that will conserve momentum with the EM drive not accelerating?
Quote from: Rodal on 10/09/2014 01:22 pmQuote from: Mulletron on 10/09/2014 01:17 pmQuote from: Rodal on 10/09/2014 01:06 pmQuote from: Mulletron on 10/09/2014 03:15 am...Can anyone explain why it would move?...McCulloch stated << the microwaves bouncing around within the cavity have inertial mass (em radiation does: that's why it can push a Solar sail) and their inertia is determined by MiHsC (quantised inertia). In MiHsC the Unruh waves are allowed only if they fit exactly within the Hubble horizon or within a local Rindler horizon, .. if the cavity wall in this case was acting like a horizon... then the microwaves at the wide end would have more inertia than those at the narrow end since more Unruh waves would fit.as a microwave beam goes from the narrow end to the wide end it gains inertial mass. Now I can try something I've used before (for the Tajmar effect [see http://arxiv.org/abs/1106.3266 ]) and say, in order to still conserve momentum (mass*velocity) for the whole system, if mass goes up then velocity must go down, and the only way to achieve that is to have the whole structure move towards the narrow end.>>I know he says that. I just modeled that (what he said) in my most recent huge post and it failed. He maintained himself it is a leap. I tried to push the "I believe button" and it still didn't work. This thing doesn't expel any reaction mass. So now I'm back in line with Dr. White. The question is how?Can you explain in as few words as possible, what alternative explanation you have for conserving momentum (instead of McCulloch's proposal to have a force pushing the whole systemtowards the narrow end) that will conserve momentum with the EM drive not accelerating?We have to react against something. That something isn't blocked by the boundary conditions of the enclosed cavity. Looks like we're back to it reacting against the QV again.......somehow.http://arxiv-web3.library.cornell.edu/abs/1404.5990 (what I've been saying) Maybe this way.