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#3260 by spupeng7 on 01 Mar, 2016 01:36
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Quote from Rodal - Thread 1: « Reply #453 on: 09/12/2014 03:49 PM »Quote
in Dr. Woodward's theory, the propagation of this gravitational reaction responsible for inertia, has INFINITE speed, which is problematic in a Theory of Relativity (where we usually associate gravitational waves to travel at the speed of light).
Dr. Woodward answers with a smile, that "presumably" it is a radiation reaction attributable to Wheeler–Feynman absorber theory. With his smile and frank facial expression he acknowledges that this is, let's say... problematic?
Because we know that:
A) The Wheeler–Feynman absorber theory assumes that the solutions of the electromagnetic field equations must be invariant under time-reversal symmetry, there is no distinction between past and future.
B) It therefore assumes that elementary particles are not self-interacting. This is a big drawback of this theory. Indeed, as demonstrated by Hans Bethe, the Lamb shift necessitated a self-energy term to be explained. Feynman and Bethe had an intense discussion over that issue and eventually Feynman himself stated that self-interaction is needed to correctly account for this effect.
C) Wheeler and Feynman conceived of this theory before the Weak Force was understood as it is nowadays. It is known that the Weak Force implies time-symmetry breaking and gives an arrow of time. Hence the Weak Force is incompatible with the Wheeler–Feynman absorber theory, in this sense.
I think that it was wise that you, Dr. White, et.al., decided that <<This paper will not address the physics of the quantum vacuum plasma thruster (QVPT), but instead will describe the recent test campaign>> (Abstract of "Anomalous Thrust Production..." paper).
In that vein, I think it would be best to discuss the experiments without addressing any controversial physical explanation for the time being.
« Last Edit: 09/12/2014 03:53 PM by Rodal »
Dr Rodal,
having finished my wide eyed reading from the beginning of Thread 6, I now journey to the wilds of Thread 1 to see what I missed at the beginning. Joys I have found there, Island Player's dada turn of phrase and the arrival of your self. Reply #453 has answered a question that has dogged me for years, why did Richard Feynman abandon the development of absorber theory after 1949.
Absorber theory appeals to me as a foundation for a universal charge interaction explanation for any emdrive thrust discovered. That all photons are interactions which occur as the locations of interacting atoms coincide within complex time, makes sense to me if the human notion of distance is in fact separation within the real component of complex time.
Because real time progresses at different rates dependent upon location within gravitational fields, distance is only logically consistent as something independent from time, from single point perspectives. Whereas mechanics and in particular wave mechanics, describe a universe which interacts within complex time consistent with the co-variant perspective.
Does this not allow the solutions of the electromagnetic field equations to be invariant under time-reversal symmetry? Does this not resolve the paradox of the wave function of quantum mechanics while still being consistent with Special Relativity?
Out of my depth mathematically with my own arguments here, treading water and trying not to be a hindrance to the progress of analysis of these strange results we are investigating. Hoping soon to address other points you raised in that fine post. Sorry to hit you with this on super Tuesday and praying that there is at least a little sense to it.
John Newell.. (spupeng7)
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#3261 by SeeShells on 01 Mar, 2016 01:46
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My messy rebuild. FYI.
Shell
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#3262 by Rodal on 01 Mar, 2016 02:07
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Quote from Rodal - Thread 1: « Reply #453 on: 09/12/2014 03:49 PM »
Quotein Dr. Woodward's theory, the propagation of this gravitational reaction responsible for inertia, has INFINITE speed, which is problematic in a Theory of Relativity (where we usually associate gravitational waves to travel at the speed of light).
Dr. Woodward answers with a smile, that "presumably" it is a radiation reaction attributable to Wheeler–Feynman absorber theory. With his smile and frank facial expression he acknowledges that this is, let's say... problematic?
Because we know that:
A) The Wheeler–Feynman absorber theory assumes that the solutions of the electromagnetic field equations must be invariant under time-reversal symmetry, there is no distinction between past and future.
B) It therefore assumes that elementary particles are not self-interacting. This is a big drawback of this theory. Indeed, as demonstrated by Hans Bethe, the Lamb shift necessitated a self-energy term to be explained. Feynman and Bethe had an intense discussion over that issue and eventually Feynman himself stated that self-interaction is needed to correctly account for this effect.
C) Wheeler and Feynman conceived of this theory before the Weak Force was understood as it is nowadays. It is known that the Weak Force implies time-symmetry breaking and gives an arrow of time. Hence the Weak Force is incompatible with the Wheeler–Feynman absorber theory, in this sense.
I think that it was wise that you, Dr. White, et.al., decided that <<This paper will not address the physics of the quantum vacuum plasma thruster (QVPT), but instead will describe the recent test campaign>> (Abstract of "Anomalous Thrust Production..." paper).
In that vein, I think it would be best to discuss the experiments without addressing any controversial physical explanation for the time being.
« Last Edit: 09/12/2014 03:53 PM by Rodal »
Dr Rodal,
having finished my wide eyed reading from the beginning of Thread 6, I now journey to the wilds of Thread 1 to see what I missed at the beginning. Joys I have found there, Island Player's dada turn of phrase and the arrival of your self. Reply #453 has answered a question that has dogged me for years, why did Richard Feynman abandon the development of absorber theory after 1949.
Absorber theory appeals to me as a foundation for a universal charge interaction explanation for any emdrive thrust discovered. That all photons are interactions which occur as the locations of interacting atoms coincide within complex time, makes sense to me if the human notion of distance is in fact separation within the real component of complex time.
Because real time progresses at different rates dependent upon location within gravitational fields, distance is only logically consistent as something independent from time, from single point perspectives. Whereas mechanics and in particular wave mechanics, describe a universe which interacts within complex time consistent with the co-variant perspective.
Does this not allow the solutions of the electromagnetic field equations to be invariant under time-reversal symmetry? Does this not resolve the paradox of the wave function of quantum mechanics while still being consistent with Special Relativity?
Out of my depth mathematically with my own arguments here, treading water and trying not to be a hindrance to the progress of analysis of these strange results we are investigating. Hoping soon to address other points you raised in that fine post. Sorry to hit you with this on super Tuesday and praying that there is at least a little sense to it.
John Newell.. (spupeng7)
Relativity has an "arrow of time": the cosmological arrow of time pointing in the direction of the universe's expansion, starting with the Big Bang and inflation. Dark energy's accelerated expansion implies an "arrow of time", as well.
On the other hand, just like Maxwell's electromagnetic equations don't have an arrow of time, but we can still use them to calculate the eigenfrequencies and eigenmodes of an electromagnetic cavity like the EM Drive, it may be valid (in some restricted sense to be determined) for Wheeler–Feynman absorber theory to be valid in certain applications. Maybe Woodward's theory is one of them. I understand that Woodward's theory also needs a flat space to be valid. The range of validity, if any, remains to be proven.
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#3263 by rfmwguy on 01 Mar, 2016 02:48
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It looks promising. 24ghz does allow for a much lower mass DUT and battery power. Good catch on thermal gradient of platform and water Mr. Li. Liquid does introduce its own new set of variables. Accoustic wave vibrations can impact a liquid medium. Not sure if their emdrive produces any accoustic noise like our power transformers do on full size units.
"Started testing the EMDrive V3 on the swimming platform.
This is the best approach so far. If his platform can swim from one side to the other then it is definite. He needs to take care of thermal isolation between the platform and the water thought. -
#3264 by Monomorphic on 01 Mar, 2016 03:01
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Generation 01, Individuals 1-3 are finished. You can see them all plotted on the graph below. Ind02 frustum is scaled 10% larger than Ind01, and Ind 03 frustum is scaled 10% smaller than Ind01. On average, this 10% difference in scale shifts the resonant mode by about 150Mhz.
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#3265 by SteveD on 01 Mar, 2016 06:57
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Just a thought about CoE:
Let's assume that the EMDrive is a form of photonic laser thruster for a minute (it's not).
Light is emitted from the small end. In the process the device gains (at least temporarily) momentum and kinetic energy.
As I showed in an earlier post, W/c means that the same amount of energy is redshifted out to produce momentum regardless of the velocity of the photon rocket.
However, as I also showed, this does not* produce an over-unity. Instead, the acceleration causes a doppler shift in the emitted light such that the doppler shifted light loses energy equal to the kinetic energy gained by the photon rocket.
If that light were to hit a, theoretical, absolutely stationary and 100% efficient absorber, the redshifted light + the KE in the rocket would = total amount of energy released (energy is conserved).
It also follows that any form of propulsion that powers itself by the redshifting photons as they are being emitted will also conform to COE as long as its efficiency follows the formula for a photonic laser thruster (2NW/C). Doppler shift will account for the energy difference between the energy actually consumed by the motive process and KE=1/2mv^2. (This may help explain CoE and Woodward's proposed effect).
If that light where to hit, instead a reflector moving at the same velocity of the spacecraft the reflector would be blown backward by W/c. This would decelerate the reflector, potentially causing it to lose more energy than W/c. In this case, though, the forward velocity of the reflector blueshifts the incoming light by an amount of energy equal to the additional KE shed by the reflector.
Which brings up an interesting thought about the EMDrive. We are assuming that Redshift due to the acceleration of the small end = blueshift due to the equal acceleration of the large end. What if the large end were to be stationary when the photons from the small end hit it? The results would be a net increase in kinetic energy of the device.
Let's say that point C is a photon emitter floating in space. Line AC is a 1 AU long length of metal and point D is a reflector connected to point A by another length of metal representing line AD. The emission of photons at point C accelerates the entire contraption forward. The Photons travel from point C to point D. However, line AD, which is longer than line CD, is shortest route between points C and A. If point A were to acceleration in less time than it took light to move from point C to point A, then superluminal communication would be possible. This suggests that when the photons arrive at point D, the fact that point D should be accelerating is not yet in its light cone. Point D is stationary.
Which still leaves CoM problems that I need to think more on.
Edit, could the geometry of the frustum or the dielectric used be increasing the reflectivity of the small end. That would mean that less photons are being emitted from the large end creation the same process in the opposite direction. The difference between the two ends = thrust.
* Actually the well-established, mainstream equations did show a small overunity at high speeds. Why this should be the case is a, very, interesting questions. -
#3266 by CW on 01 Mar, 2016 08:45
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Relativity has an "arrow of time": the cosmological arrow of time pointing in the direction of the universe's expansion, starting with the Big Bang and inflation. Dark energy's accelerated expansion implies an "arrow of time", as well.
On the other hand, just like Maxwell's electromagnetic equations don't have an arrow of time, but we can still use them to calculate the eigenfrequencies and eigenmodes of an electromagnetic cavity like the EM Drive, it may be valid (in some restricted sense to be determined) for Wheeler–Feynman absorber theory to be valid in certain applications. Maybe Woodward's theory is one of them. I understand that Woodward's theory also needs a flat space to be valid. The range of validity, if any, remains to be proven.
Could one say, that time is pointed in the direction of entropy increase? -
#3267 by Chrochne on 01 Mar, 2016 08:50
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I guess this counts as the end of February, when the BBC Horizons program on the EMDrive was previously said to be broadcast.
If I've managed to miss it, it has left no trace on the BBC iPlayer, and passed completely without comment here. I'd deduce that it hasn't gone out as expected.
Does anyone (?TT) have any light to shed on what might be happening?
R.
Yes it should, but I think they were expecting that EW will release their latest paper on the EmDrive by that time. It did not yet happen. As far as I heard, BBC sometimes prepare programs even half a year in advance before releasing it. I would really guess that they will postpone it till the news are out.
So far I would give that paper from EW time. We all know their latest paper caused storm that I have never seen before. NASA PR knows that as well. They would really want to make sure that it has all the details it needs, before advancing further.
I know we are all expecting that paper. We all know what it can mean for humanity (or not according to critics of course), but we need to give them space, even if it will take longer than expected. We were fortunated that Star-Drive shared the news with us, but as you can see NASA PR Hammer very likely hits hard and he seems not to be able to share with us any updates at the moment. -
#3268 by A_M_Swallow on 01 Mar, 2016 10:45
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I guess this counts as the end of February, when the BBC Horizons program on the EMDrive was previously said to be broadcast.
Yes, Phil told me a couple of weeks ago that BBC2 pulled their future schedule off their website in a bit of an unusual move. We don't think it had anything to do with Shawyer, just some programming issues.
If I've managed to miss it, it has left no trace on the BBC iPlayer, and passed completely without comment here. I'd deduce that it hasn't gone out as expected.
Does anyone (?TT) have any light to shed on what might be happening?
R.
Britain has decided to hold a referendum on whether to leave or stay in the European Union. For the next few weeks this political question will be filling British documentaries and current affairs programs. A scientific documentary may be shown after the referendum.
Level of seriousness - succession of the Irish Free State from the UK in 1920 and succession of the Southern States from the USA. Both activities involved wars. -
#3269 by Rodal on 01 Mar, 2016 12:19
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Yes, but entropy's "thermodynamic arrow of time" is extrinsic to the theory of General Relativity. Entropy has to be added to a General Relativity formulation. Entropy is an emergent property of a system:Relativity has an "arrow of time": the cosmological arrow of time pointing in the direction of the universe's expansion, starting with the Big Bang and inflation. Dark energy's accelerated expansion implies an "arrow of time", as well.
On the other hand, just like Maxwell's electromagnetic equations don't have an arrow of time, but we can still use them to calculate the eigenfrequencies and eigenmodes of an electromagnetic cavity like the EM Drive, it may be valid (in some restricted sense to be determined) for Wheeler–Feynman absorber theory to be valid in certain applications. Maybe Woodward's theory is one of them. I understand that Woodward's theory also needs a flat space to be valid. The range of validity, if any, remains to be proven.
Could one say, that time is pointed in the direction of entropy increase?
* a measure of disorder within a macroscopic system
* the amount of information that would be needed to specify the full state of the system
* Hawking added the concept of "gravitational entropy" of black holes: he defined it as a global quantity
Some older views on this (https://en.wikipedia.org/wiki/Entropy_(arrow_of_time)#Cosmology) are:QuoteIn the first scenario, the cosmological arrow of time is the reason for both the thermodynamic arrow of time and the quantum arrow of time. Both will slowly disappear as the universe will come to a halt, and will later be reversed.
In the second and third scenarios, it is the difference between the initial state and the final state of the universe that is responsible for the thermodynamic arrow of time. This is independent of the cosmological arrow of time. In the second scenario, the quantum arrow of time may be seen as the deep reason for this.
However, these older views don't take into account the accelerated expansion due to dark energy. It seems that we need to understand the nature and origin of dark energy, to comprehend what is the deep reason for the cosmological arrow of time.
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#3270 by JohnFornaro on 01 Mar, 2016 12:23
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Let's assume that the EMDrive is a form of photonic laser thruster for a minute (it's not).
Why? -
#3271 by Rodal on 01 Mar, 2016 12:39
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A photonic laser thruster has two separate vehicles flying in opposite directions:Let's assume that the EMDrive is a form of photonic laser thruster for a minute (it's not).
Why?
with the photons bouncing back and forth in space between the two space vehicles that get further and further apart from each other.
In contrast, the EM Drive is one vehicle hermetically sealed (according to its proponents): the microwaves cannot escape the copper cavity, which they penetrate only to within 1 micrometer skin depth. So in what sense can the single cavity EM Drive concept be compared to the two vehicles comprising the photonic laser thruster? -
#3272 by meberbs on 01 Mar, 2016 13:01
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Just a thought about CoE:
...
As I showed in an earlier post, W/c means that the same amount of energy is redshifted out to produce momentum regardless of the velocity of the photon rocket.
However, as I also showed, this does not* produce an over-unity. Instead, the acceleration causes a doppler shift in the emitted light such that the doppler shifted light loses energy equal to the kinetic energy gained by the photon rocket.
...
* Actually the well-established, mainstream equations did show a small overunity at high speeds. Why this should be the case is a, very, interesting questions.
You apparently missed my previous post that pointed out that you used the wrong equations in the wrong context.
Short version: Redshift of an emitted photon is the difference in energy of the photon between 2 different reference frames, but CoE does not apply across reference frame transformations. (Note this is different than redshift of a reflected photon, in which case both photon frequencies are measured in the same reference frame.) -
#3273 by Monomorphic on 01 Mar, 2016 21:01
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I'm trying to get as close to a real magnetron as possible with these sims. Right now i'm using a monopole, but am not sure of a few dimensions. I don't have my RF source yet, but if someone has a 2.45Ghz magnetron lying around, will you please measure the antenna for me? Length, width, diameter etc. I'm assuming the primary material is copper, so please let me know if that is different too.
BTW i've noticed a 5% increase in efficiency if the antenna is aligned perpendicular to the side walls rather than parallel with the end plates. Hope to have some data on that soon.
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#3274 by rfmwguy on 01 Mar, 2016 22:06
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Sounds like the reason programming changed. As a student of the civil war, don't think the EU is comparable to the usa in both longevity and purpose. I'll love the UK whether its EU or not. Have many friends and fond travel memories of England...it will be OK regardless. Thanks for insightful input.I guess this counts as the end of February, when the BBC Horizons program on the EMDrive was previously said to be broadcast.
Yes, Phil told me a couple of weeks ago that BBC2 pulled their future schedule off their website in a bit of an unusual move. We don't think it had anything to do with Shawyer, just some programming issues.
If I've managed to miss it, it has left no trace on the BBC iPlayer, and passed completely without comment here. I'd deduce that it hasn't gone out as expected.
Does anyone (?TT) have any light to shed on what might be happening?
R.
Britain has decided to hold a referendum on whether to leave or stay in the European Union. For the next few weeks this political question will be filling British documentaries and current affairs programs. A scientific documentary may be shown after the referendum.
Level of seriousness - succession of the Irish Free State from the UK in 1920 and succession of the Southern States from the USA. Both activities involved wars. -
#3275 by spupeng7 on 01 Mar, 2016 23:42
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Quote from Rodal - Thread 1: « Reply #453 on: 09/12/2014 03:49 PM »
Quotein Dr. Woodward's theory, the propagation of this gravitational reaction responsible for inertia, has INFINITE speed, which is problematic in a Theory of Relativity (where we usually associate gravitational waves to travel at the speed of light).
Dr. Woodward answers with a smile, that "presumably" it is a radiation reaction attributable to Wheeler–Feynman absorber theory. With his smile and frank facial expression he acknowledges that this is, let's say... problematic?
Because we know that:
A) The Wheeler–Feynman absorber theory assumes that the solutions of the electromagnetic field equations must be invariant under time-reversal symmetry, there is no distinction between past and future.
B) It therefore assumes that elementary particles are not self-interacting. This is a big drawback of this theory. Indeed, as demonstrated by Hans Bethe, the Lamb shift necessitated a self-energy term to be explained. Feynman and Bethe had an intense discussion over that issue and eventually Feynman himself stated that self-interaction is needed to correctly account for this effect.
C) Wheeler and Feynman conceived of this theory before the Weak Force was understood as it is nowadays. It is known that the Weak Force implies time-symmetry breaking and gives an arrow of time. Hence the Weak Force is incompatible with the Wheeler–Feynman absorber theory, in this sense.
I think that it was wise that you, Dr. White, et.al., decided that <<This paper will not address the physics of the quantum vacuum plasma thruster (QVPT), but instead will describe the recent test campaign>> (Abstract of "Anomalous Thrust Production..." paper).
In that vein, I think it would be best to discuss the experiments without addressing any controversial physical explanation for the time being.
« Last Edit: 09/12/2014 03:53 PM by Rodal »
Dr Rodal,
having finished my wide eyed reading from the beginning of Thread 6, I now journey to the wilds of Thread 1 to see what I missed at the beginning. Joys I have found there, Island Player's dada turn of phrase and the arrival of your self. Reply #453 has answered a question that has dogged me for years, why did Richard Feynman abandon the development of absorber theory after 1949.
Absorber theory appeals to me as a foundation for a universal charge interaction explanation for any emdrive thrust discovered. That all photons are interactions which occur as the locations of interacting atoms coincide within complex time, makes sense to me if the human notion of distance is in fact separation within the real component of complex time.
Because real time progresses at different rates dependent upon location within gravitational fields, distance is only logically consistent as something independent from time, from single point perspectives. Whereas mechanics and in particular wave mechanics, describe a universe which interacts within complex time consistent with the co-variant perspective.
Does this not allow the solutions of the electromagnetic field equations to be invariant under time-reversal symmetry? Does this not resolve the paradox of the wave function of quantum mechanics while still being consistent with Special Relativity?
Out of my depth mathematically with my own arguments here, treading water and trying not to be a hindrance to the progress of analysis of these strange results we are investigating. Hoping soon to address other points you raised in that fine post. Sorry to hit you with this on super Tuesday and praying that there is at least a little sense to it.
John Newell.. (spupeng7)
Relativity has an "arrow of time": the cosmological arrow of time pointing in the direction of the universe's expansion, starting with the Big Bang and inflation. Dark energy's accelerated expansion implies an "arrow of time", as well.
On the other hand, just like Maxwell's electromagnetic equations don't have an arrow of time, but we can still use them to calculate the eigenfrequencies and eigenmodes of an electromagnetic cavity like the EM Drive, it may be valid (in some restricted sense to be determined) for Wheeler–Feynman absorber theory to be valid in certain applications. Maybe Woodward's theory is one of them. I understand that Woodward's theory also needs a flat space to be valid. The range of validity, if any, remains to be proven.
Dr Rodal,
is this the same arrow of time which points backward in many Feynman diagrams. Would quantum mechanics be feasible without those backward arrows? -
#3276 by masterharper1082 on 02 Mar, 2016 00:17
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Relativity has an "arrow of time": the cosmological arrow of time pointing in the direction of the universe's expansion, starting with the Big Bang and inflation. Dark energy's accelerated expansion implies an "arrow of time", as well.
On the other hand, just like Maxwell's electromagnetic equations don't have an arrow of time, but we can still use them to calculate the eigenfrequencies and eigenmodes of an electromagnetic cavity like the EM Drive, it may be valid (in some restricted sense to be determined) for Wheeler–Feynman absorber theory to be valid in certain applications. Maybe Woodward's theory is one of them. I understand that Woodward's theory also needs a flat space to be valid. The range of validity, if any, remains to be proven.
Could one say, that time is pointed in the direction of entropy increase?
Or... could one say that time progression itself is a form of entropy? A while ago, someone commented on the possibility that time might be able to, at least temporarily and in special circumstances, reverse, though the long-term effect would be a net increase. That sounds very much like the theory of non-equilibrium thermodynamics. -
#3277 by SeeShells on 02 Mar, 2016 01:08
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I'm trying to get as close to a real magnetron as possible with these sims. Right now i'm using a monopole, but am not sure of a few dimensions. I don't have my RF source yet, but if someone has a 2.45Ghz magnetron lying around, will you please measure the antenna for me? Length, width, diameter etc. I'm assuming the primary material is copper, so please let me know if that is different too.
BTW i've noticed a 5% increase in efficiency if the antenna is aligned perpendicular to the side walls rather than parallel with the end plates. Hope to have some data on that soon.
Makes some sense as it's using the sidewall as the ground plane. It's interesting to know though and do you see the same using the waveguide being parallel to the side wall?
Here is a link for some close ups of the magnetron antenna and I just mic'd it out for you.
http://imgur.com/a/6C9yu
The antenna doesn't actually touch the launching cap but sits down from it 3mm under the cap. Also it doesn't end in a wire point but a wedge. 7.25mm deep and 10mm at the wide part of the wedge on the top.
http://imgur.com/8LsmKCj
Hope this helps.
Best To You,
Shell -
#3278 by aceshigh on 02 Mar, 2016 02:00
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Responding to your comments, I want to clarify that this site (NSF) is not associated in any official way with NASA or any other United States Government administration. The majority of the people writing comments here are not working for NASA. Several posters have never worked for NASA in their lifetime.
Some of us are from countries that can barely build a rocket without it exploding and killing half of the rocket scientists in the country.
Our current countries and NASA will setup being meaningful if EM Drive works. Just like ancient city-states of Greece. -
#3279 by Rodal on 02 Mar, 2016 03:02
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...
No, it is not the same as the cosmological arrow of time.
Dr Rodal,
is this the same arrow of time which points backward in many Feynman diagrams....
Dr Rodal,
Would quantum mechanics be feasible without those backward arrows?
The Schrödinger equation ( https://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation ), is time-symmetric: it has no arrow of time.
Some people make arguments about a quantum arrow of time based on wave function collapse, but this interpretation is very debatable to this date.
Concerning Feynman's idea that all electrons could in fact be the same electron, just bouncing back and forth in time, and that antimatter is actually matter moving backwards in time, it is safe to say that most physicists don't believe that antimatter is actually matter moving backwards in time. Feynman's idea inspired him to calculate what the properties of an electron moving backwards in time would be,matching the known properties of the positron. It was a useful inspiration in the 1940's. I don' think that Feynman insisted on that idea as something physical, particularly later on in his career, in the 1960's and later.