Author Topic: EM Drive Developments - related to space flight applications - Thread 10  (Read 1151019 times)

SeeShells

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #60 on: 05/24/2017 07:30 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.

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 :-)
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

Rodal

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #61 on: 05/24/2017 08:06 PM »
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 :-)
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
Hi Shell,

Yes,  but we need further theoretical and experimental work

Notsosureofit was working on it, a lot of this is tied with entropy.

The curvature of space can also be measured with entropy measures

(K.-T. Sturm, On the geometry of metric measure spaces, Acta Math. 196 (2006), n 1, 65–177. https://projecteuclid.org/euclid.acta/1485891805
https://projecteuclid.org/euclid.acta/1485891806   )

The idea is that, in positive Ricci curvature (like the curvature of a sphere), “midpoints spread out”: if we take two geometrical measures in the curved 4 D spacetime surface, and consider the set of points that lie “halfway” between the two sets then the set of midpoints is wider than expected from the Euclidean (flat) case. (For example, on a sphere, the set of midpoints of the two poles will be the whole equator.)

The reverse is true for negative Ricci curvature (like the curvature of a saddle).

In the entropy approach one uses probability measures instead of geometrical measures in the  4 D spacetime surface. The extent to which they are spread can be evaluated using the relative entropy (the Kullback–Leibler divergence  https://en.wikipedia.org/wiki/Kullback%E2%80%93Leibler_divergence ).

I wonder whether Notsosureofit did any further work?
« Last Edit: 05/24/2017 08:09 PM by Rodal »

ThatOtherGuy

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #62 on: 05/24/2017 08:32 PM »
Shell, please don't take offense, I was just kidding !
I was calling my lab this for quite some time... no offense. OK?
Hugs,
Shell

Fine, lady, I just wanted to be sure ... language barriers (on my side) sometimes play bad jokes hugs from me too !
« Last Edit: 05/25/2017 08:56 AM by ThatOtherGuy »

ThatOtherGuy

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #63 on: 05/24/2017 08:37 PM »
Maybe I'm totally off target but ... what if one modulates the signal injected into the cavity? I mean ... using different waveforms

Rodal

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #64 on: 05/24/2017 08:47 PM »
Maybe I'm totally off target but ... what if one modulates the signal injected into the cavity? I mean ... using different waveforms

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

« Last Edit: 05/24/2017 08:53 PM by Rodal »

ThatOtherGuy

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #65 on: 05/24/2017 09:00 PM »
Jose ... yes, but I was thinking to less random waveforms, some regular ones (as simple or complex as you want)

corrected the post, swapped Paul and Jose
« Last Edit: 05/25/2017 10:42 AM by ThatOtherGuy »

LowerAtmosphere

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #66 on: 05/25/2017 02:52 AM »
Paul ... 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 sinusoidal shape though choosing chirp length or the quantity of superimposed chirps can change the shape of the wave considerably, allowing for on-the-go adjustments or periodic oscillations to waveform (and eigenmodes!). You could get creative with it. Which makes me wonder what would happen if you took a metallic toroid and excited a series of chirped waves in it. Would it still act as a time crystal even if the amplitude of the wave in the interference pattern periodically changed? I mean to say the pattern would result in a constant positive but changing superposition of the two waves. I know it has to do with the quantum system correlation and the time-evolution is not dependent on a particular wave-function but rather their superposition, but different superpositions should result in different time evolutions and clock rate peaks, shouldn't it*? This hasn't been empirically tested before. If the negative wave component is unnecessary to keep the differently wound phases coherent in a metallic ring then what does that imply for metallic and symmetric resonant cavities? Controversial thought: is the EM Drive thrust simply the decay of a coherent system and the phase of the system briefly exceeds the physical motion creating a time translation symmetry breaking event. I don't think it is currently, but once we make higher quality super-cooled less noisy cavities, then suddenly we have to consider these quantum effects, especially when interference patterns occur due to multiple inputs. Might also be interesting for nanocavity research. Not implying any FTL=phase velocity=group velocity fallacies, just curious about the behaviour of particles in closed metallic paths under multiple simultaneous inputs. Likely, this is all unrealistic, as the cavity is far too messy and imperfect - not to mention the numerous possibilities for diffraction, etc - but even if it decoheres quickly, there must be a short window in which such symmetry breaking occurs periodically and/or randomly.

Among other papers you should know this one on time crystals... https://arxiv.org/pdf/1603.08001v4.pdf
Also see this paper regarding the stability of minkowski space... https://arxiv.org/pdf/gr-qc/0408073v1.pdf

It is wise to accept the strange reality of gravitational waves and negative energy creating anisotropic energy dispersion. Especially curious how the above linked theory "disproves" negative energy. It is very interesting to spend time thinking about small wave packets which are 'isolated' from the rest of the phase and which carry a negative density. Would they induce time lag, decohere systems, interact with the system or would the system mostly 'ignore' it like a bug on a windscreen or an unwelcome rogue ion? Imagine 4 Chlorine ions in a n-sized-ring of Aluminum for example. I am curious about a wave form which, for example, has null points at those parts of the molecular chain. See the attached paper for an example of huge bond variations and consider what sort of interesting effects you could achieve if you repeated rings such as this throughout a hypothetical cavity. Surely a stack of such rings would result in a metamaterial with different charged regions. Put one of the negatively charged regions next to a modal peak and instant faster thrusting (or less thrusting due to less, in terms of total #, though stronger gravity gradients) Perhaps somebody could venture a guess.

Just some thoughts, hopefully they make sense.

*Also, what if the superimposed waves were negative as discussed towards the end, as far as I understand it shouldn't matter for symmetry breaking. Even if that is the case wouldn't the gravity tensor alter the electron density at the outer skin, destabilizing the flow and decohering the entire system? Even if this is wrong, at the very least I'm surprised I haven't seen any discussion on this anywhere.
« Last Edit: 05/25/2017 04:42 PM by LowerAtmosphere »

masterharper1082

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #67 on: 05/25/2017 03:55 AM »
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.

I gave it a skim... the ratio of essay to data and math doesn't bode well.
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

ThatOtherGuy

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #68 on: 05/25/2017 10:17 AM »
Paul ... 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.

same line of thought here, I was thinking about interferences as well

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).

not just square waves, by the way, for example an overposition of square and sine waves may be interesting, but then it will be needed to experiment to find out if and how different waveforms alter the EMdrive cavity behavior

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.

Same thought, although, again, at the moment it's just "fried air" without any kind of evidence, that's why I asked if someone already tried exploring (even just using simulations) such an approach

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.pdf
Also see this paper regarding the stability of minkowski space... https://arxiv.org/pdf/gr-qc/0408073v1.pdf
[...]

snipped more interesting stuff, need some time to digest the ideas and the papers, thanks for those

RERT

Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #69 on: 05/25/2017 03:34 PM »
Re: Ricci tensor & Einstein tensor. Having finally located my notes, one can quickly show that Rμν=0 ⇔ Gμν=0

By definition, Rμν= Gμν +˝(gμνR)    Rμν=0 ⇒R=0⇒Rμν= Gμν⇒Gμν=0

But the trace of the Einstein tensor is G=-R  So Gμν=0 ⇒G=0⇒R=0⇒Rμν= Gμν⇒Rμν=0

I can say this with some feeling as a guy who calculated the tensor in detail in a free-space solution before the slap-the-forehead moment...

ThatOtherGuy

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #70 on: 05/25/2017 05:32 PM »
Just tried an ixquick (http://www.ixquick.com) search for "microwave cavity interference pattern" (w/o quotes) and got back some interestng results ... ranging from Darthmouth to Stuttgart, worth a seekout imVVHo
« Last Edit: 05/25/2017 05:33 PM by ThatOtherGuy »

WarpTech

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #71 on: 05/25/2017 10:31 PM »

All: "Apprentice Sorcerer Gravity Appliances Reaction Devices (ASGARD) works for me!    I just hope Thor doesn't mind...

Nope, don't mind in the slightest!

I'd be more worried about Loki!

spupeng7

Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #72 on: 05/26/2017 02:31 AM »
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.
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
Thankyou mh,
bedtime reading that may disturb your dreams... yes I did like some of it but the 5D argument complicates. I use complex time to argue that interaction is direct and that unification can be achieved by simplification. I agree with Beichler when he argues that a point has extension, because separation of the dimensions is artificial.

The extension of a point charge apparent to me, is the reaction its acceleration causes at separation ict. "What is real and what is mathematics devoid of physical content", is a sticky question for me. I am asking myself to believe that action at a distance is real.

Allowing the vacuum to have properties other than extension with direction, disturbs me. Would it not be simpler to accept action at a distance and see if that allows gravity to be the slightly unequal sum of electrical attractions and repulsions? Looking, of course, for a collaborator with the mathematical fluency required to make this argument properly
Optimism equals opportunity.

Notsosureofit

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #73 on: 05/26/2017 05:29 PM »
FYI: https://arxiv.org/pdf/1607.03118.pdf

Entropy theorems in classical mechanics, general relativity, and the gravitational
two-body problem

(Dated: August 30, 2016)

"In classical Hamiltonian theories, entropy may be understood either as a statistical property of
canonical systems, or as a mechanical property, that is, as a monotonic function of the phase space
along trajectories. In classical mechanics, there are theorems which have been proposed for proving
the non-existence of entropy in the latter sense. We explicate, clarify and extend the proofs of these
theorems to some standard matter (scalar and electromagnetic) field theories in curved spacetime,
and then we show why these proofs fail in general relativity; due to properties of the gravitational
Hamiltonian and phase space measures, the second law of thermodynamics holds. As a concrete
application, we focus on the consequences of these results for the gravitational two-body problem,
and in particular, we prove the non-compactness of the phase space of perturbed SchwarzschildDroste
spacetimes. We thus identify the lack of recurring orbits in phase space as a distinct sign of
dissipation and hence entropy production."

Note: It is the existence of recurring "orbits" in "free energy" arguments that gives me reason to dismiss them out of hand.
« Last Edit: 05/26/2017 05:33 PM by Notsosureofit »

R.W. Keyes

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #74 on: 05/28/2017 06:39 AM »
<puts on experimenter's cap>
How about 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 noise 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 some frequency 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 VNA 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, to use the old expression.

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's cap, dons theoretician's 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 spent 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
« Last Edit: 05/28/2017 09:12 AM by R.W. Keyes »

Bob Woods

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #75 on: 05/28/2017 07:43 AM »
<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.

Mezzenile

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #76 on: 05/28/2017 08:19 AM »
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 :-)
The price to pay for these situations where space-time curvature occurs even when there is no stress energy-momentum tensor distribution, is that it is impossible to say where the corresponding gravitational energy is localized (this is the energy pseudo-tensor usually associated to gravitational waves).

These pseudo-tensors have some rather strange properties.  If "wrong" coordinates are chosen then the energy pseudo-tensors is non-zero even in flat empty spacetime.  By another choice of coordinates, they can be made zero at any chosen point, even in a spacetime full of gravitational radiation.  So the pseudo-tensors are not able to provide a good local definition of energy density, although their integrals are sometimes useful as a measure of total energy.

One other point on which the energy pseudo-tensor (gravitational energy) differs from classical energy/matter is that it cannot act  itself as a source of gravity as modelised by Einstein fundamental equation of General Relativity (G = 8 Pi  T). The only indirect way by which it can act as a source of gravity modification is through the non-linearity of the Einstein Field Equations which govern the space-time curvature evolution (propagation phenomena where for example a gravitational wave interacts with the local background curvature of space-time).

So in General relativity ther are several "kind" of energy and there is generaly speaking, no overall conservation law  encompassing all these kinds of energy. It is only in very special situation where space-time geometry has specific boundary conditions that overall energy conservation can have a meaning (this is linked to the possibilty then to apply famous Noether theorems)
« Last Edit: 05/28/2017 08:33 AM by Mezzenile »

R.W. Keyes

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #77 on: 05/28/2017 08:49 AM »

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.

The invitation is appreciated, and reciprocated. I have a whole list of people, from Albany to Portland, in Oregon that I need to take up on their offers to visit. Oregonian beer culture is well renowned, but I wonder if I could find a brew out there without the huge amount of hops that I typically see, and which interfere with my digestion.

As to my Westfield, I am new to the precise area, but it is part of Western Mass that I know very well, being a native. Westfield has two airbases nearby, one gun manufacturer (Savage), and along history of metalworking (due to its close proximity to the former Springfield Armory). It is known as 'the whip city', because of its ancient dominance in manufacture of buggy whips, and was also home to Columbia bicycles. It is currently home to a state university, formerly a teachers school. and not far from the campus of the University of Massachusetts (in Amherst) as well as a smattering of other colleges.

My situation in it is my own company/lab, which is primarily focused on 3D printing, but has enough room for my many other interests. Once I have some substatial EMdrive-related facilities, I will post some bragging pictures, but the factory/lab/office is in an industrial area about three miles from the apartment I live in, and is a bit dingy compared to what SeeShells has.

as a side note, I own a fairly large (5500+ sf) but dilapidated building in the city I used to live in (Pittsfield) which I would gladly donate to some good use, such as an NPO for Emdrive research. But it would require at least \$25,000 to get it to adequate state to be used. It's got 3-phase 220V, so that's a plus. Consider this a notice to anyone who is in need of a space and can sink the work & money into it; there might be grants / loans available to make it happen. I really need to do something with the building soon, so any proposals, no matter how incomplete, should be discussed soon before I sell it at auction and take a huge loss.

Anyhow, I want to return the focus of this list to its major technical focus, and encourage people with proposals or plans to meet up to contact me through the private message facility here. This goes for business regarding to my 3D printing business as well.

--RWK, at nearly dawn

SeeShells

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #78 on: 05/28/2017 02:48 PM »
Maybe I'm totally off target but ... what if one modulates the signal injected into the cavity? I mean ... using different waveforms

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

Dr. Rodal,

I go back to a time I learned the basics of electronics with tubes, transistors where the new wonder toy IC's were stuff of dreams. The magnetron is nothing but a tube that self excites to produce microwaves. This isn't rocket science but tube science. Tubes are still around and still are used in the semiconductor industry where signal splatter and jitter have to be tightly controlled.

This is the one of the first articles I ran across that reinforced what I knew of tubes and what caused issues. http://lea.hamradio.si/~s57uuu/mischam/magnetr/

I was able to build a thermally stabilized water cooled current and voltage controlled supply locked into Fo by the use of a waveguide > antenna this gave me a very stable signal with no AM jitters and side lobes.

It's not entirely true that a magnetron is nasty noisy and unusable as a RF device it's just tougher to do than a lower wattage SS device.

I do plan to go to a SS device sometime in the near future although for now the toughness of a magnetron tube and support hardware suits what I'm doing quite well and if I do blow it up and make matchstick from magic smoke it's a less than 50 bucks to replace it.

My Very Best,
Shell

PS: Currently I'm getting all the machinery setup and oiled and checked out as some stuff I've had in storage. Ran air into the tool room yesterday and today start hauling all the drills, nuts bolts and setting up all the bins for my nuts, screws, drill buts, washers in about a 100 little bins. Guarantee you I'll be ready to fire up the grill later to burn up something and wash it down with a frothy brew after.

PSS: Sticky Shift key LeFt Caps on aNd Off hapHazardly, need a new KB. Fixed it I hope.

One more thing: I had a dear friend donate a new/old Tektronix O-Scope for the lab, there is something about a simple O-scope that I love, the new stuff on the computer via the USB port is OK but green wiggly lines on a CRT make me smile a lot.
« Last Edit: 05/28/2017 03:56 PM by SeeShells »

Augmentor

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Re: EM Drive Developments - related to space flight applications - Thread 10
« Reply #79 on: 05/28/2017 04:28 PM »
Shell,

You could always go to a klystron.

D

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