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#860 by tchernik on 22 Sep, 2016 21:46
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My only advice is to be critical of Flying Car talk...nowhere do I have evidence this is anything other than an advanced (mN) space propulsion solution rivaling Ion Drive. FWIW
I agree. All that talk about upcoming hyper-strong drives goes against the credibility and seriousness of the topic, regardless of how much we would like it to be true, because any discussion assuming it quickly devolves into science fiction daydreaming.
But mostly because there is no evidence of such a thing, not even Mr. Shawyer has come with any demonstration like that (or we wouldn't be fussing about minute forces).
As I said before here and in other forums: any device that is proven to exist and that has an efficiency above of a photon rocket is a revolution. That's the important aspect to prove.
Even if you can only get millinewtons per kilowatt from it, that's enough for changing physics and impacting all known space propulsion technologies. -
#861 by Bob012345 on 22 Sep, 2016 22:00
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Another poster here (I have unfortunately lost track of who) posted a quite thorough proof and explanation of why devices that operate like the EMDrive as self contained units emitting no mass, and having in their own frame a constant force / input power greater than 1/c must therefore be a free energy machine. Their analysis included explanations of how to account for the energy properly in this case for a chemical rocket.
Hopefully someone else thought to save the link and can point you to that post.
The short version is that this is a real problem, and saying otherwise is simply wrong. (Note that some of the better proposed theories for the EMDrive include ways around this, by making the EMDrive not a closed system, but Shawyer doesn't do this)
Thanks. It's a fascinating problem and I have been giving a lot of thought lately. It is well know that the upper stage of a multi-stage chemical rocket can yield far more kinetic energy than is accounted for by just the chemical energy of it's fuel. In principle, any device that has a self generated constant force will hit eventually run into the energy conundrum. It's not just an EMDrive thing as you say. In fact, one can buy little electric toy airplane motors that give 27 oz of thrust for 85 watts which amounts to 0.088N/W or 88N/KW. Rounding to 0.1 N/W and assuming an input of 100W, a 1Kg self powered device on a frictionless surface would run into the conundrum in about 2 seconds assuming a acceleration of 1g. After that the input power times the time is less than the kinetic energy in the lab frame according to my calculations. I have not tried this in a physical device, just thought experiments. My point is that the energy conundrum is not confined to some esoteric set of conditions, it is totally testable under very nominal conditions in any lab probably by a freshman physics class. But of course no one in their right mind would openly bother to try it if anyone else knew about it and if it worked, you really couldn't tell anyone either! But it's fun to ponder.
Of course if a ship increases it's velocity by some amount using a given energy, there is always a reference frame (an infinite number of them) where the increase in kinetic energy observed is far greater than the release of energy in the ships frame. But does than make it a problem? I really don't think so. As I mentioned before, if light power, 1/c, is the theoretical maximum usable without creating energy conundrums, then using photon recycling, which we know works from experiments, even over part of a trip might in principle break that.
The massic Energy of classical fuel must be taken into account. Even if it is not used directly to increase the Kinetic Energy of the ship, it participates. Once this Energy taken into account, there is no more Kinetic Energy paradox for upper stages.
It would be interesting to calculate what speed would be needed to get the paradox with an Emdrive. But I am afaid it needs high speed...
People like to say that, that if you include the kinetic energy of the fuel before it burns, there is no paradox. Of course, but the problem is that no one can point to where all the extra energy was actually put in beyond the already burned fuel. In other words, it takes the same amount of energy for every spec of velocity gain, not more when it's going faster. So saying the kinetic energy of the fuel must be accounted for does not resolve the paradox, it magnifies it.
It's easy to calculate the speed the Emdrive or Cannae drive reach that point. You just need the acceleration and the power used for thrust and the mass. Set Power times time to kinetic energy. Substitute a*t for v and you get t=2*power/(mass* acceleration^2). In the Cannae Deep Space Probe, that works out to about 267 seconds! In the Shawyer Interstellar probe (29.6KW thruster, 8936 Kg mass, about 1m/s^2 acceleration) about 6.6 seconds. So failure would be known quickly.
Your argument about the traditional rocket is not correct. The main fallacy is that you did not count the fact that the higher the speed of the rocket is, the more energy the fuel has. This extra energy is stored as kinetic energy (exactly 1/2mV^2, on top of the chemical energy stored), which was provided by the already burn fuel. If you count that in, your paradox is resolved.
I thought I said that. My point is that happens naturally. You don't need to burn extra fuel to account for that. Each delta v requires the same burn, not more to account for the fact that future fuel is more effective. The reason we don't see more paradoxes with rockets is that they require so much mass that they run out before that point would be reached and they are so very inefficient so most kinetic energy is wasted.
Also, I don't consider the energy issue a paradox if you use the work-energy theorem. It's the mechanical power times the time that always equates to the kinetic energy change in every observer frame. So there is no paradox. There is just a mixing of energy from different frames that confuses people.
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#862 by qraal on 22 Sep, 2016 23:03
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The reason we don't see more paradoxes with rockets is that they require so much mass that they run out before that point would be reached and they are so very inefficient so most kinetic energy is wasted.
Rockets are quite efficient at turning stored energy into kinetic energy. But it depends on what you mean by "efficiency". If we're talking the ratio of the energy stored in the propellant/fuel to the kinetic energy of the vehicle at burn-out, then rockets get a maximum efficiency of 0.63 for a mass-ratio of 4.91. That's a well known fact and it's pretty impressive efficiency compared to most other engines. The engine in your car converts about 11% of the energy in the fuel into kinetic energy thanks to all the friction and thermodynamic losses. Or, if you have a hybrid, it might be more like ~25%.
Of course you might be thinking of the kinetic energy tied up in *just* the payload, but that's not really a proper measure of efficiency, unless you have something more mass-efficient in mind, like a linear accelerator or similar electric drive. And, of course, stage rockets have to drop bits in order to get their mission velocity, but that's a whole other issue. -
#863 by rhubley on 22 Sep, 2016 23:18
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I can only tell you of my personal collaboration, but not any specifics...as agreed upon. There is an EmDrive builders network in which data, techniques and plans are shared privately. All in the group have honored each other's commitment not to divulge anything discussed there publicly.
Its very open, but we all hold back a little info, especially when we are not convinced of its relevancy or accuracy.
I understand why this happens but it is a loss to progress and scientific understanding to have groups go private/dark just to avoid caustic criticism. Others may also label it as a "distraction" to communicate their experiments/results as they happen but it's critical to do so. It's not easy to ignore or politely respond to some forms of criticism but I do believe it does benefit us as experimentalists to hear and respond to it. Avoiding it just leads to groups hoarding data, going down dead ends un-necessarily, and retarding the advancement of the field. Please consider being as open as possible with your experiments and data. You will no doubt be highly esteemed in the end if you do so.
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#864 by rfmwguy on 22 Sep, 2016 23:33
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You probably need to view my EmDrive videos on the youtube channel: https://www.youtube.com/channel/UCm54FS3u2aDeutnMsV0cITg/videosI can only tell you of my personal collaboration, but not any specifics...as agreed upon. There is an EmDrive builders network in which data, techniques and plans are shared privately. All in the group have honored each other's commitment not to divulge anything discussed there publicly.
Its very open, but we all hold back a little info, especially when we are not convinced of its relevancy or accuracy.
I understand why this happens but it is a loss to progress and scientific understanding to have groups go private/dark just to avoid caustic criticism. Others may also label it as a "distraction" to communicate their experiments/results as they happen but it's critical to do so. It's not easy to ignore or politely respond to some forms of criticism but I do believe it does benefit us as experimentalists to hear and respond to it. Avoiding it just leads to groups hoarding data, going down dead ends un-necessarily, and retarding the advancement of the field. Please consider being as open as possible with your experiments and data. You will no doubt be highly esteemed in the end if you do so.
Then my v-cast (at 25 min in):
Recent test data here and http://reddit/r/qthruster
Think you'll find extreme transparency on my 2 year journey w/the emdrive -
#865 by Monomorphic on 22 Sep, 2016 23:33
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I have nearly completed a full 3d model and FEKO analysis of the Cannae drive tested in vacuum by EW. Mode TM010
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#866 by rhubley on 22 Sep, 2016 23:44
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You probably need to view my EmDrive videos on the youtube channel: https://www.youtube.com/channel/UCm54FS3u2aDeutnMsV0cITg/videos
Then my v-cast (at 25 min in):
Recent test data here and http://reddit/r/qthruster
Think you'll find extreme transparency on my 2 year journey w/the emdrive
Oh yes...I haven't missed a second of it and I applaud what you, Seashells, Monomorphic and others are doing. I am simply responding to your remarks about private groups, holding back results until they are validated ( no need to do so if you are clear about their possible flaws ) and the slight pullback of reporting by Seashells for perhaps similar reasons. Ok....stepping back into the shadows.
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#867 by Bob Woods on 23 Sep, 2016 03:00
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There will still be organized resistance against it, made up of competing technology interests and those unwilling to accept there is something new they didn't predict nor understand. That can be very difficult for some to accept. From my humble DIY perspective, its real and should lead towards other discoveries.
You know Dave, the list of people here who have opened minds to possibilities and new thought is pretty long. Thanks for doing your part with an openness that is, quite frankly, new to science and the world. Open collaboration, to all who care to participate.
Thank you, very much. -
#868 by SeeShells on 23 Sep, 2016 05:10
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Hi all,
http://ssi.org/ssi-woodward-propulsion-workshop/
Just got home (very tired) from the Space Studies Institute Advanced Propulsion Workshop in Estes Park Colorado where it not only met my high exceptions but, exceeded them by several magnitudes.
More tomorrow....
My Best,
Shell -
#869 by meberbs on 23 Sep, 2016 05:32
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Note: I am cutting out much of the context from these quotes, but that is why the link back to the original post is there on this forum. I am just including enough to communicate what I am part of the original posts I am responding to.
In principle, any device that has a self generated constant force will hit eventually run into the energy conundrum.
This is only true if it doesn't expel anything mass or have a (massive) to push against. The other non-EMDrive examples you gave like an RC airplane aren't relevant because they have a medium (air).Of course if a ship increases it's velocity by some amount using a given energy, there is always a reference frame (an infinite number of them) where the increase in kinetic energy observed is far greater than the release of energy in the ships frame. But does than make it a problem? I really don't think so.
No, this isn't a problem, because energy obviously changes when you change reference frames. This is not the paradox I and others here are referring to.As I mentioned before, if light power, 1/c, is the theoretical maximum usable without creating energy conundrums, then using photon recycling, which we know works from experiments, even over part of a trip might in principle break that.
This is using light as a medium for 2 object to push against each other, again no issue, because the object at each end of the recycling is effectively the exhaust of the other one. Energy gets pulled out of the beam through redshift, so it needs continuous (probably increasing) input power as well.The reason we don't see more paradoxes with rockets is that they require so much mass that they run out before that point would be reached and they are so very inefficient so most kinetic energy is wasted.
No, there are no paradoxes with rockets seen, because there are none. You can do all of the calculations for a rocket in a reference frame going at 0.9 c relative to the starting velocity of the rocket, and you would not find any imbalance paradox.Also, I don't consider the energy issue a paradox if you use the work-energy theorem. It's the mechanical power times the time that always equates to the kinetic energy change in every observer frame. So there is no paradox. There is just a mixing of energy from different frames that confuses people.
Again, the different frames thing is not the issue. Let's see if I can explain this simply (I wish I could find that old post)
Ignoring relativity briefly:
Spacecraft with initial mass of 10, moving at velocity 100 = 100,000 (kinetic) energy
Lets say it has 2 (equal mass) parts connected with a compressed spring storing 4000 energy.
Upon release (and constraining to 1 dimension) One half would be moving at speed 120 and have 72000 energy, and the other would end up with speed 80, and 32,000 energy. The "exhaust" has to be included, otherwise the half that started having only 50,000 energy, couldn't end up with 72,000 energy from a potential energy store of 4000.
If there wasn't exhaust Conservation of Energy (CoE) would be broken.
Relativity actually creates a tiny loophole: Because in relativity E2 = (m*c2)2 + (p*c)2 momentum can be gained without exhaust that has (rest) mass. This only works up to a momentum/energy ratio of 1/c, which not coincidentally is the energy/momentum ratio that special relativity enforces on all massless particles. This includes gravitons/gravity waves. (Technically this is only known for sure in the small spatial curvature limit, because it is hard to define momentum and energy in full general relativity.)
If the EMDrive works (exceeding the above ratio), and does not push against something (e.g. degradable quantum vacuum, pushing against other massive bodies, etc.) it is a free energy machine. Shawyer's description of how the device works (which is what started this conversation) does not have it pushing on anything, so according to Shawyer's claims it would be a free energy device. -
#870 by Flyby on 23 Sep, 2016 07:28
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Hi all,
Hi Shell,
http://ssi.org/ssi-woodward-propulsion-workshop/
Just got home (very tired) from the Space Studies Institute Advanced Propulsion Workshop in Estes Park Colorado where it not only met my high exceptions but, exceeded them by several magnitudes.
More tomorrow....
My Best,
Shell
must say I'm really supersized to see how small the work group actually was....
so.. (expectations)³ huh? Can't wait to hear more...
And seriously.. a double rainbow?
how cool is that to make a "goodbye" pic... -
#871 by Slyver on 23 Sep, 2016 08:25
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I understand why this happens but it is a loss to progress and scientific understanding to have groups go private/dark just to avoid caustic criticism. Others may also label it as a "distraction" to communicate their experiments/results as they happen but it's critical to do so. It's not easy to ignore or politely respond to some forms of criticism but I do believe it does benefit us as experimentalists to hear and respond to it. Avoiding it just leads to groups hoarding data, going down dead ends un-necessarily, and retarding the advancement of the field. Please consider being as open as possible with your experiments and data. You will no doubt be highly esteemed in the end if you do so.
Regardless of what rfmwguy has posted about “holding data back”, both he and monomorphic have been prolific in their data sharing. TheTraveler has been forthcoming to an extent, but no real data has been posted by him. In his defense, it seems he is still waiting on the equipment he desires to perform the more conclusive experiments he has designed. SeaShells is taking a very different approach. She has shared no data (to my knowledge), though she has shared much of her design and processes. I cannot fault her for her approach, even if it does not make me overly happy personally.
In 1989 Fleishman and Pons published data that turned the world on its head. (They knew it was not ready to be published, because their methodology was not nailed down, but someone else leaked it for them.) It was a very unfortunate turn of events because they had not experimentally determined a proper methodology. This one event has forever (or at least forever since) changed the way scientists view publishing their information. What has happened since then in that field is completely amazing (especially the last 15 years or so), but very few know (or are willing to admit that they know) about the mountains of data that exist. This is the fallout of too quickly published data without a co-published properly repeatable experiment. People aren’t even allowed to say the words “cold fusion” without being instantly dismissed as idiots. It is imo the lowest point of our history of science since the 16th century.
SeaShells apparently does not want to follow such a pattern. I do not know her at all personally, but from reading this forum every day for the past 2? years, it seems she is a very careful and accomplished engineer. I respect her decisions, because the media is obviously following this thread. I hope she is not TOO cautious, and recognizes that the pattern of data sharing that monomorphic and rfmwguy have shown has not been overly problematic, but it is what it is, and again, I have come to have complete respect for what she has shared of her methodologies, and of course, her decisions.
We are all impatient. For me, it has been a couple years of waiting in the shadows. I have sufficient education I could attempt these experiments myself, but I do not have the luxury of excess time, and it would take up much of what I do have to do it justice. More importantly, I doubt I could outperform our current list of DIYers, NASA EW, and whoever else has taken on this project, so I remain an interested secondary (impatient but respectful) observer.
I suggest to everyone; appreciate what is happening here. It is remarkable. I have never seen a collaboration in such a medium that is actually effective in getting to the bottom of a potentially earth shattering mystery (or the opposite, as the case may be). Appreciate what we are given. It is more than I could have ever dreamed possible outside of a group of people I know personally. Don’t be afraid to ask for more, but don’t be upset if it doesn’t happen. Just appreciate, that is all.
Slyver -
#872 by TheTraveller on 23 Sep, 2016 08:59
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Shawyer's description of how the device works (which is what started this conversation) does not have it pushing on anything, so according to Shawyer's claims it would be a free energy device.
His claim is a small % of the momentum in the internal EmWave is transferred to the external frustum. Most of the energy in the frustum exits as heat as in the attached image from his peer reviewed paper.
Bottom line is the EmDrive generates a force and accelerates a mass while it consumes energy to do so.
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#873 by Gilbertdrive on 23 Sep, 2016 11:41
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Shawyer's description of how the device works (which is what started this conversation) does not have it pushing on anything, so according to Shawyer's claims it would be a free energy device.
His claim is a small % of the momentum in the internal EmWave is transferred to the external frustum. Most of the energy in the frustum exits as heat as in the attached image from his peer reviewed paper.
Bottom line is the EmDrive generates a force and accelerates a mass while it consumes energy to do so.
What referential for Kinetic Energy ? in GR you do not have an absolute reference frame. What is your reference frame for Kinetic Energy ?
As I calculated a few pages ago, the 0.67C (relatively to the earth referential) mentionned in the Shawyer peer-rewieved paper means a Kinetic Energy of 3.1191599*10^20 joules
Since the 10 years of operation of the 200Kwe generator gives only 6.311*10^13 Joules
So, following Shawyer, at the expanse of 6.311*10^13 Joules a spaceship can get 3.1191599* 10^20 joules of Kinetic Energy. We get massive free energy ! -
#874 by SeeShells on 23 Sep, 2016 12:25
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Hi all,
Hi Shell,
http://ssi.org/ssi-woodward-propulsion-workshop/
Just got home (very tired) from the Space Studies Institute Advanced Propulsion Workshop in Estes Park Colorado where it not only met my high exceptions but, exceeded them by several magnitudes.
More tomorrow....
My Best,
Shell
must say I'm really supersized to see how small the work group actually was....
so.. (expectations)³ huh? Can't wait to hear more...
And seriously.. a double rainbow?
how cool is that to make a "goodbye" pic...
Think that rainbow was strange? You're not the only one. The photo doesn't do it justice, it hurt your eyes to look at it, it was incredibly bright.
If you and others don't mind. I'm going to let others more highly qualified present the breakthrough propulsion details along with the papers, summaries and videos that were done. It was three days of very serious discussions on the Woodward Mach effect, NASA's findings on the EMDrive and a few other ideas thrown in. Nothing was taken for granted.
What I learned was a deeper understanding of what I need to do with my own testing and evaluating of this drive in finer detail, removing error sources, and quantifying the ones I can't and putting the data in context. Presented by people who wrote the book on it. It was all good.
And when driving back down the mountains into Denver the very first song on the radio was Rocket Man. You figure that one out.
My Best,
Shell
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#875 by Star One on 23 Sep, 2016 12:35
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Shell,
Good to hear you had a productive time. -
#876 by TheTraveller on 23 Sep, 2016 12:42
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What referential for Kinetic Energy ? in GR you do not have an absolute reference frame. What is your reference frame for Kinetic Energy ?
Pick one from an infinite number. Each will give you a different value. Which is correct or maybe none are?
One thing we do know is the amount of energy that the ship's electrical generator would produce to indirectly provide constant force to generate a constant acceleration of the ship's mass according to A = F/M. -
#877 by Gilbertdrive on 23 Sep, 2016 13:08
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What referential for Kinetic Energy ? in GR you do not have an absolute reference frame. What is your reference frame for Kinetic Energy ?
Pick one from an infinite number. Each will give you a different value. Which is correct or maybe none are?
In that case, why claim that the Emdrive does not violate CoE ?
In the earth reference frame, the Shawyer article shows a clear violation of CoE. But Shawyer claims that Conservation of Energy is still true. He should assume his emdrive as a free energy device.
Also, if you assume that different referential gives different results, why are you writing about Kinetic Energy ? When you write about Kinetic Energy, you need to have a reference frame. If a reference frame is not something relevant to the way it is working, do not speak of Kinetic Energy (bottom of Fig 12)
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#878 by TheTraveller on 23 Sep, 2016 13:35
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...He should assume his emdrive as a free energy device...
The work done by the electrical energy supply to accelerate the mass of the ship does not generate free energy. It is just work done on the ship's mass and most of it is turned into heat energy. There is no energy gain, no free energy.
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#879 by RotoSequence on 23 Sep, 2016 13:45
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...He should assume his emdrive as a free energy device...
The work done by the electrical energy supply to accelerate the mass of the ship does not generate free energy. It is just work done on the ship's mass and most of it is turned into heat energy. There is no energy gain, no free energy.
Unless I am mistaken (it wouldn't be the first time
), relative velocity and kinetic energy doesn't care about how much waste heat you have; an indefinite acceleration period and greater than photon rocket thrust (eventually) works out to more kinetic energy than input power. Still, in my opinion, this is a problem that merely needs to be resolved in theoretical frameworks (assuming EM drive works), not an ultimate proof that EM drives don't work.
), relative velocity and kinetic energy doesn't care about how much waste heat you have; an indefinite acceleration period and greater than photon rocket thrust (eventually) works out to more kinetic energy than input power. Still, in my opinion, this is a problem that merely needs to be resolved in theoretical frameworks (assuming EM drive works), not an ultimate proof that EM drives don't work.