Quote from: Rodal on 05/23/2017 02:06 pm...There are fundamental differences between gravitation and electromagnetism, even considering the field theory without any quantization.One very interesting thing about gravitation is that in 4 spacetime (3 D space + time) (*) one can have a zero stress-energy tensor, and still have non-zero energy and momentum in the gravitational field. This follows from the fact that zero right hand side of the gravitational field equation (zero stress-energy tensor), means zero left hand side (zero Einstein's tensor). But zero Einstein tensor in 4 spacetime does not necessarily mean a flat spacetime. The equality is between the Einstein tensor and the stress-energy tensor. Zero Einstein tensor does not equal a flat spacetime geometry. The Einstein tensor is equal to the difference between the Ricci tensor and the scalar curvature (times the metric tensor). Both can add up to zero, and yet have non-zero components. ADDED IN EDIT: In 4 dimensions the Ricci tensor can be zero and yet the space be curved: non-flat. Since Ricci tensor equal zero does not necessarily mean flat spacetime, therefore one can have zero stress-energy tensor in 4 spacetime and still have non-zero energy and momentum in the gravitational field ! One can have gravitational wave disturbances with zero source: zero stress-energy density tensor. This is very different from electromagnetism where the electromagnetic fields (photons) do not carry any charge. In a gravitational field one can have a zero energy density, and still have gravitational waves. Thus we have self-interaction in gravitation due to the nonlinearity of the gravitational equations. A gravitational wave with a small energy relative to the curvature will travel along a null geodesic in the curved spacetime geometry. This is a different path than it would travel in the absence of the spacetime curvature. Thus one can have self-interaction: the gravitational field interacting with itself.This issue involves energy conservation and self-interaction in 4D spacetime, something that many posters discussing "overunity" really struggle with. In General Relativity you can have energy and momentum on the left hand side of the equation, unlike charges in electromagnetism (electromagnetic waves in vacuum or in space without charges do not carry any charge: photons have no charge).(*) This is only possible in 4 spacetime (3 D space + time) and higher. In 3 spacetime (2 D space + time) a zero stress-energy tensor necessarily implies a zero curvature of spacetime (because in 3 dimensions or less zero Ricci tensor means flatness) and hence in 3 spacetime (2 D space + time) the gravitational field would not be able to carry energy and momentum. In 4 spacetime electromagnetism, the electromagnetic fields (photons) do not carry any charge. ADDED IN EDIT:The issue has to do with the number of components of the tensor that specifies curvature of space: the number of independent components of the Riemann curvature tensor. The Riemann curvature tensor has 4 indices:But the curvature tensor that appears in Einstein's equation is not the Riemann curvature tensor, but is instead the Ricci tensor which has only two indices: In 3 D the Ricci tensor has 6 independent components, exactly the same number of independent components as the Riemann curvature tensor has in 3 D: also 6. Therefore, in 3 D, vanishing of the Ricci tensor implies also vanishing of the Riemann curvature. In 3 D, vanishing of the stress-energy tensor implies vanishing of the Ricci tensor, and vanishing of the Ricci tensor implies vanishing of the Riemann curvature. Hence in 3 D vanishing of the stress-energy tensor implies a flat geometry. However in 4 D, the Ricci tensor has 10 independent components and the Riemann curvature tensor has 20 independent components. For 4 dimensions or greater, there will be fewer components of the Ricci tensor than components of the Riemann tensor. Hence for 4 dimensions or greater, the Ricci tensor can vanish, and yet the Riemann curvature tensor may not vanish. Therefore for 4 dimensions or greater vanishing of the stress-energy tensor does not imply flatness of spacetime.Example: in 4 D spacetime gravitational plane waves have zero Ricci curvature tensor but non-zero Riemannian curvature. In the region of the gravitational wave disturbance spacetime is not flat, even though the RIcci tensor is zero. The energy and momentum of these gravitational plane waves is not in the energy-stress tensor, but the energy and momentum are in the gravitational field itself. The stress-energy tensor represents the energy due to matter, but stress-energy tensor includes NO contribution from gravitational energy or momentum in the field itself. When a binary pulsar emits gravitational waves, these waves will carry away energy away and therefore its orbital period should change. The energy and momentum are in the gravitational wave itself. Thus, in general relativity you can have energy and momentum in gravitational waves, on the left hand side of the equation, on the field itself. And these wave can interact nonlinearly. All very interesting from an energy conservation point of view :-)
...There are fundamental differences between gravitation and electromagnetism, even considering the field theory without any quantization.One very interesting thing about gravitation is that in 4 spacetime (3 D space + time) (*) one can have a zero stress-energy tensor, and still have non-zero energy and momentum in the gravitational field. This follows from the fact that zero right hand side of the gravitational field equation (zero stress-energy tensor), means zero left hand side (zero Einstein's tensor). But zero Einstein tensor in 4 spacetime does not necessarily mean a flat spacetime. The equality is between the Einstein tensor and the stress-energy tensor. Zero Einstein tensor does not equal a flat spacetime geometry. The Einstein tensor is equal to the difference between the Ricci tensor and the scalar curvature (times the metric tensor). Both can add up to zero, and yet have non-zero components. ADDED IN EDIT: In 4 dimensions the Ricci tensor can be zero and yet the space be curved: non-flat. Since Ricci tensor equal zero does not necessarily mean flat spacetime, therefore one can have zero stress-energy tensor in 4 spacetime and still have non-zero energy and momentum in the gravitational field ! One can have gravitational wave disturbances with zero source: zero stress-energy density tensor. This is very different from electromagnetism where the electromagnetic fields (photons) do not carry any charge. In a gravitational field one can have a zero energy density, and still have gravitational waves. Thus we have self-interaction in gravitation due to the nonlinearity of the gravitational equations. A gravitational wave with a small energy relative to the curvature will travel along a null geodesic in the curved spacetime geometry. This is a different path than it would travel in the absence of the spacetime curvature. Thus one can have self-interaction: the gravitational field interacting with itself.This issue involves energy conservation and self-interaction in 4D spacetime, something that many posters discussing "overunity" really struggle with. In General Relativity you can have energy and momentum on the left hand side of the equation, unlike charges in electromagnetism (electromagnetic waves in vacuum or in space without charges do not carry any charge: photons have no charge).(*) This is only possible in 4 spacetime (3 D space + time) and higher. In 3 spacetime (2 D space + time) a zero stress-energy tensor necessarily implies a zero curvature of spacetime (because in 3 dimensions or less zero Ricci tensor means flatness) and hence in 3 spacetime (2 D space + time) the gravitational field would not be able to carry energy and momentum. In 4 spacetime electromagnetism, the electromagnetic fields (photons) do not carry any charge. ADDED IN EDIT:The issue has to do with the number of components of the tensor that specifies curvature of space: the number of independent components of the Riemann curvature tensor. The Riemann curvature tensor has 4 indices:But the curvature tensor that appears in Einstein's equation is not the Riemann curvature tensor, but is instead the Ricci tensor which has only two indices: In 3 D the Ricci tensor has 6 independent components, exactly the same number of independent components as the Riemann curvature tensor has in 3 D: also 6. Therefore, in 3 D, vanishing of the Ricci tensor implies also vanishing of the Riemann curvature. In 3 D, vanishing of the stress-energy tensor implies vanishing of the Ricci tensor, and vanishing of the Ricci tensor implies vanishing of the Riemann curvature. Hence in 3 D vanishing of the stress-energy tensor implies a flat geometry. However in 4 D, the Ricci tensor has 10 independent components and the Riemann curvature tensor has 20 independent components. For 4 dimensions or greater, there will be fewer components of the Ricci tensor than components of the Riemann tensor. Hence for 4 dimensions or greater, the Ricci tensor can vanish, and yet the Riemann curvature tensor may not vanish. Therefore for 4 dimensions or greater vanishing of the stress-energy tensor does not imply flatness of spacetime.
Quote from: Rodal on 05/24/2017 03:31 amExample: in 4 D spacetime gravitational plane waves have zero Ricci curvature tensor but non-zero Riemannian curvature. In the region of the gravitational wave disturbance spacetime is not flat, even though the RIcci tensor is zero. The energy and momentum of these gravitational plane waves is not in the energy-stress tensor, but the energy and momentum are in the gravitational field itself. The stress-energy tensor represents the energy due to matter, but stress-energy tensor includes NO contribution from gravitational energy or momentum in the field itself. When a binary pulsar emits gravitational waves, these waves will carry away energy away and therefore its orbital period should change. The energy and momentum are in the gravitational wave itself. Thus, in general relativity you can have energy and momentum in gravitational waves, on the left hand side of the equation, on the field itself. And these wave can interact nonlinearly. All very interesting from an energy conservation point of view :-)Very interesting Dr. Rodal. You're way beyond my pay grade, although I think I can see what you're trying to convey. If a drive is done right and you're inciting a gravitational 4D effect (like the Mach effect) you will not have the issue of over unity and violate conservation laws.My Best,Shell
Example: in 4 D spacetime gravitational plane waves have zero Ricci curvature tensor but non-zero Riemannian curvature. In the region of the gravitational wave disturbance spacetime is not flat, even though the RIcci tensor is zero. The energy and momentum of these gravitational plane waves is not in the energy-stress tensor, but the energy and momentum are in the gravitational field itself. The stress-energy tensor represents the energy due to matter, but stress-energy tensor includes NO contribution from gravitational energy or momentum in the field itself. When a binary pulsar emits gravitational waves, these waves will carry away energy away and therefore its orbital period should change. The energy and momentum are in the gravitational wave itself. Thus, in general relativity you can have energy and momentum in gravitational waves, on the left hand side of the equation, on the field itself. And these wave can interact nonlinearly. All very interesting from an energy conservation point of view :-)
Quote from: ThatOtherGuy on 05/24/2017 07:07 pmShell, please don't take offense, I was just kidding !I was calling my lab this for quite some time... no offense. OK? Hugs,Shell
Shell, please don't take offense, I was just kidding !
Maybe I'm totally off target but ... what if one modulates the signal injected into the cavity? I mean ... using different waveformsWas this already experimented?
Paul ... yes, but I was thinking to less random waveforms, some regular ones (as simple ir complex you want)
Quote from: Star-Drive on 05/23/2017 06:49 pmAll:I ran across a paper on the unification of GRT and QM this morning that IMO we all need to consider in regards to what is real and what is mathematics devoid of physical content.Best, Paul M.I gave it a skim... the ratio of essay to data and math doesn't bode well.
All:I ran across a paper on the unification of GRT and QM this morning that IMO we all need to consider in regards to what is real and what is mathematics devoid of physical content.Best, Paul M.
Quote from: ThatOtherGuy on 05/24/2017 09:00 pmPaul ... yes, but I was thinking to less random waveforms, some regular ones (as simple ir complex you want)Good question. I have been thinking about interference and propagation.
If you have two diametrically opposed identical injection points pumping out square waves with peak and trough perfectly matched and coherent then you could increase the average density of the resulting wave packets through constructive interference (some people argue it is already occurring in the cavity).
Also this assumes minimal splatter and noise. Ultimately, such an interference pattern would just increase the efficiency of the energy input as each injection point uses half (or less) of the wattage, together they produce areas with a combined higher amplitude wave perhaps proving useful if energy requirements are insufficiently met by say solar panels in deep space.
Other waveforms you could consider are using a (or multiple superimposed) chirped pulses to change the shape of the power (and loading) graph or perhaps test whether pulsing the cavity with energy is the only factor in thrust. The time dependent average of the input should be a relatively flat net positive oscillating [...]Among other papers you should know this one on time crystals... https://arxiv.org/pdf/1603.08001v4.pdfAlso see this paper regarding the stability of minkowski space... https://arxiv.org/pdf/gr-qc/0408073v1.pdf[...]
Quote from: Star-Drive on 05/23/2017 06:43 pmAll: "Apprentice Sorcerer Gravity Appliances Reaction Devices (ASGARD) works for me! I just hope Thor doesn't mind...Nope, don't mind in the slightest!
All: "Apprentice Sorcerer Gravity Appliances Reaction Devices (ASGARD) works for me! I just hope Thor doesn't mind...
Quote from: Star-Drive on 05/23/2017 06:49 pmAll:I ran across a paper on the unification of GRT and QM this morning that IMO we all need to consider in regards to what is real and what is mathematics devoid of physical content.Best, Paul M.spupeng7, a lot of similarities to concepts you have proposed, due to a 5D model, whether it is truly complex time or ?? Perhaps there is good food for thought there.As a non-physicist, his historical/narrative style helped me to visualize where he is trying to go. Of course, in the end, only experiments and correct math matter. He does claim that his theory is falsifiable.Not sure if his other papers include derivations, or just more talk... more than enough reading already tonight.mh
<puts on experimenter cap>Going for the best and highest Q, before testing for acceleration? But at what frequency? People seem to like 2.4 Ghz because of the availability of magnetrons for it, but there's a lot of RF in that band. Magnetrons seem to be dismissed because of their noisiness (even if there are ways to stabilize them, does it matter at experimenter's power levels?) Why not use something a bit lower? Maybe just below it in the 2300-2310 Mhz band (Amateur), or a lot lower at 1240-1300 Mhz (also Amateur). Might make VNE analysis more precise, but at the expense of larger cavities. Also, I haven't given up the idea of metal spinning on a high-accuracy & precision CNC spinning lathe. I think it's impractical for me to try to acquire the tools and learn the practice myself, especially as I live in an area with many small metal shops - one of them is likely to do decent spin-forming. Of course, for high-Q I'd then want to go for superconducting end plates which is a bit more daunting.I am just raising some ideas up the flagpole here, to see if anyone salutes. By the way, I have moved to Westfield, Mass. If anyone on this forum is in the general area it would be great to get together and toss ideas back and forth.<takes off experimenter cap, dons theoreticians hat>In case any of you are interested, I find myself becoming more convinced of Dr. Mike McCullough's theories. Quantum inertia, horizon mechanics, whatever you want to call it. Ockham's razor etc. I don't expect everyone to agree with me. I am more interested in experimentation than theory, but only because I think that good experiments are in short supply.<takes off hat, does not don another>For you in the USA, I hope you have a happy holiday weekend. I spend much of today hiking in the woods, fighting mud, mosquitoes, and high humidity. I'd really like to find a place for a good fire pit on Monday, but it seems unlikely, and useless as rain is predicted.--RWK
RW if you ever make it to Oregon, I'd be happy to show you some hikes. I'm old and disabled and can't hike any more, but I can show you some great places, and some great beer to boot.Ditto for the rest of you. Coming this way, let me know.
Quote from: ThatOtherGuy on 05/24/2017 08:37 pmMaybe I'm totally off target but ... what if one modulates the signal injected into the cavity? I mean ... using different waveformsWas this already experimented?Not intentionally (not with the intention to achieve an express purpose) to my knowledge, except that magnetrons by their nature already contain amplitude, frequency and phase modulation