Cannae/EmDrive

[Sean Mirrsen]

The problem with that analogy, is that the sheep-counting experiment so far yields a small number of suspiciously yellow, curvy, elongated sheep. Until we find whether it's the work of some idiot with a paint bucket and too much free time - even if it's the logical thing to assume - we can still make assumptions about the bananas' involvement in the results, because the idiot is either not there or very good at hiding, and simply assuming he's there and searching for him without considering the possible signs of a banana revolution may bite us in the ass later on.

Edited February 20, 2015 by Sean Mirrsen

[magnemoe]

Depends on how much thrust can be achieved.

If it can replace booster rockets? Expect a big boom as space suddenly becomes much more available.

If not, it's still a boon for stuff that's already in orbit, but the boom wouldn't be as big unless some other boost solution becomes available.

No it will not affect launches at all, the trust is low as in ion engine performance so it will replace ion engines, it will also open new options because of unlimited dV like asteroid jumping until breakdown, with an good reactor it will make manned and deep space missions far easier and because you can accelerate until turnover you will get more effect for long burns, not much harder to get an probe into Pluto orbit than Jupiter.

- - - Updated - - -

The problem with that analogy, is that the sheep-counting experiment so far yields a small number of suspiciously yellow, curvy, elongated sheep. Until we find whether it's the work of some idiot with a paint bucket and too much free time - even if it's the logical thing to assume - we can still make assumptions about the bananas' involvement in the results, because the idiot is either not there or very good at hiding, and simply assuming he's there and searching for him without considering the possible signs of a banana revolution may bite us in the ass later on.

Yes, read that some thermal effect might explain the trust also in vacuum, sounds a bit weird as it looks like trust depend on resonance frequencies but this is obviously something you want to test for.

Electromagnet effects sounds far more likely to me, they measured that effect to be 10uN and subtracted it but it might be other overlooked effects here.

In short its very high probably an fluke however the upside is so large its worth to continue.

But cold fusion is more likely as it don't break fundamental physical laws.

[perk]

But cold fusion is more likely as it don't break fundamental physical laws.

that depends on your understanding of "cold", overcoming the coloumb-barrier without putting as much energy into the fusing particles to do it sure breaks physics...

[orbital mechanic]

If this thing always produces constant thrust per constant power input without propellant and with higher efficiency than a photon drive then it seems unavoidable that it can be turned into a free energy machine, as there will be some speed (less than c) after which it will be gaining more kinetic energy than the energy you put in.

[K^2]

that depends on your understanding of "cold", overcoming the coloumb-barrier without putting as much energy into the fusing particles to do it sure breaks physics...

There are legitimate ways to lower the barrier, though. Muon catalysis, for example, brings it down enough for reaction to take place at cryogenic temperatures. And in fact, if we had a much more efficient way to produce muons, it would even produce net power output. I wouldn't take any cold fusion claims without a truckload of salt, but there are no fundamental contradictions. Just piles upon piles of engineering ones.

[perk]

sorry, i should have clarified that my comment only refered to the fusing of "ordinary" atoms not fusing of muonic atoms

[KerikBalm]

You mean like the H+/ATPase proton pump that was eventually rediscovered as the mitochondrial ATP synthase, the process of elimination forced scientist to accept that the pump was running in reverse because no alternative mitochondrial ATP synthase could be found. Ironically this is the largest producer of ATP in the cell. Go figure.

You seem to be leaving out the fact that they show that the ATP synthase was neccessary for ATP synthesis.

They didn't just say: Its not A, its not B, and we only know of A, B, and C, so therefore it must be C.

They showed that C was neccessary and sufficient.

They showed in vitro that a proton gradient could catalyze the ADP+Pi -> ATP only with addition of the purified ATP synthase.

They also showed that production of the ATP correlated with a decrease in the proton gradient.

http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1997/illpres/history.html

"1937 - Herman Kalckar (Denmark) establishes that ATP synthase is linked with cell respiration.

1961 - The American Ephraim Racker isolates the F1 part of the ATP synthase.

1961 - Peter Mitchell (UK) shows that cell respiration leads to differing concentrations of hydrogen ions (pH) inside and outside the mitochondrial membrane (the chemiosmotic hypothesis).

1964 - Paul D. Boyer proposes that ATP is synthesised through structural changes in the ATP synthase enzyme.

1973 - Boyer discovers that the step in ATP synthesis which requires energy is the release of ATP and the binding of ADP together with Pi ("The Binding Change Mechanism").

1981 - John E. Walker determines the DNA sequence of the genes encoding the proteins in ATP synthase.

1994 - The structure of the F1 part of the ATP synthase is determined by Walker and co-workers.

1996-1997 - The hypothesis that parts of ATP synthase rotate during the synthesis and hydrolysis of ATP is demonstrated chemically (Richard Cross, USA), spectroscopically (Wolfgang Junge, Germany) and microscopically (Masasuke Yoshida, Japan)."

Moreover, it was shown that it is specifically the gamma subunit of ATP synthase that is needed for ATP synthase activity, and without it, one can infact get ATPase activity from the same complex.

Since then, there was Itoh, H., et al., Nature, 29 January 2004.

They attached magnetic beads to the rotary part of the compex, and using a magnetic field were able to make it rotate. If they spun it one way, it produces ATP, if they spun it the other way, or didn't spin it at all, it catalyzed the ATP-> ADP + Pi reaction

They had direct evidence that it was ATP synthase... they didn't just do a "process of elimination" and then leave it at that and ask others to accept the result.

Having been in science for decades, having seen all kinds of old dogma fall and new fluff (e.g. cold-fusion) fall I am not going to stick my neck out either direction. I will make a point though about science and its sometimes blindspots. There is a disease it was identified over 2500 years ago, it was studied from 1850 to WWII by several research centers in England, Continent and US. In 1948 the cause was identified by something that was so ubiquitous in the environment that no trained professional could see it, it was not scientist that actually uncovered the thing. It was warriors that actually pealed back the veil.

I wonder what sort of scientist you've been... you seem to have literature knowledge... but you distort the facts to support your own conclusions...

http://en.wikipedia.org/wiki/Coeliac_disease#History

"While a role for carbohydrates had been suspected, the link with wheat was not made until the 1940s by the Dutch paediatrician Dr. Willem Karel Dicke."

"Dicke noticed that the shortage of bread led to a significant drop in the death rate among children affected by CD from greater than 35% to essentially zero. He also reported that once wheat was again available after the conflict, the mortality rate soared to previous levels.[112] The link with the gluten component of wheat was made in 1952 by a team from Birmingham, England.[113] Villous atrophy was described by British physician John W. Paulley in 1954 on samples taken at surgery.[114] This paved the way for biopsy samples taken by endoscopy.[7]"

So... who were these non-scientist warriors that apparently only you know about?

Edited February 20, 2015 by KerikBalm

[PB666]

There is never a deficit of energy or momentum when virtual particles are involved. Simplest case. Electromagnetic interaction between two electrons. To first order, electron emits a virtual photon, which is absorbed by second electron. The energy and momentum of the virtual photon are taken out of the first electron and deposited into the second electron.

The part where people get confused is that kinetic energy of a virtual particle can be negative. There can be other weirdness as well, due to the particle not being on the shell. But the total energy and total momentum are always conserved.

Yes yes, but for photons planck's time when the photon is in flight it never aged, either in a Dirac or otherwise matter has lost a bit of mass, detected when photon is absorbed. From the photons point of view it was never in transit, it never had transit energy. Other fields, vacuum fields could act the same with VP gains, simply carry them away and transfer them to reinstances of VP somewhere else.

[K^2]

Yes yes, but for photons planck's time when the photon is in flight it never aged, either in a Dirac or otherwise matter has lost a bit of mass, detected when photon is absorbed. From the photons point of view it was never in transit, it never had transit energy. Other fields, vacuum fields could act the same with VP gains, simply carry them away and transfer them to reinstances of VP somewhere else.

Yay! You just invented pushing stuff with magnets! Have yourself a cookie. Also, realize that this limits interaction range for the same reason why you can't have two magnets interact from many kilometers apart, unless they are really large magnets.

Oh, and there isn't a "photon's point of view," even for real photons. A virtual photon isn't even following a null path. It can jump from A to B instantly, or take a year to travel one centimeter. All of these paths contribute to virtual particle exchanges.

The entirety of your knowledge seems to be picked up from popularized science shows and articles, and maybe a bit of Wikipedia. If you want to actually be able to talk about virtual particles, you need a course in Classical Mechanics, Electridynamics, Quantum Mechanics, Special Relativity, Introductory Particle Theory, and Introductory Quantum Field Theory. Typically takes about 3-4 years in college into the first year of Master's program. If you actually want to undertake this, I can point you at some books to start with.

sorry, i should have clarified that my comment only refered to the fusing of "ordinary" atoms not fusing of muonic atoms

But nothing's to stop you from turning ordinary atoms into muonic ones. That's kind of the point. There are loop-holes in just about everything that you might practically want to do. It's kind of what applied sciences are all about. The key is to distinguish understanding all of the rules, and knowing how to exploit them to achieve seemingly impossible goals, from charlatans or honestly misguided individuals who simply press on under a naive delusion that any rule can be broken. Any rule can be circumvented, and that's far from being the same.

Conservation of energy and momentum are the most fundamental principles we know. I'm prepared to discuss that with anyone who actually understands where these come from. If one doesn't understand Noether's Theorem, and one wishes to keep insisting that we can't possibly know for sure that these are fixed, one would be much wiser to just shut up. Trying to bet on any tech that violates these is beyond dumb. If we are deciding between funding that and alchemical search for philosopher's stone, it would be stupid not to invest in the stone.

But it's not the same thing as saying, "Here's your delta-V, good luck." There's a connection between 4-velocity and 4-momentum, but it can be nudged. In fact, that condition is always violated for virtual particles. They don't have to even be moving in the same direction as their momentum points. More usefully, it is violated by warp drives. FTL travel results in causality violations, and there's a pretty well-argumented conjecture in GR that suggests that it will always require exotic matter, which may or may not be possible to attain in any significant quantities. But on the other hand, no such restrictions exists for sub-light warp. I'm not aware of a viable configuration that allows sub-light warp without exotic matter, but at least that's on the table. There is nothing says that it doesn't exist. In fact, a lot of things suggest that it probably does. A good ion drive, a power supply, and a sub-light warp, and you can go anywhere in the Solar System within hours.

This is far beyond anything the EMDrive is promising, and it's very plausible. And here we are, instead of funding theoretical research into things we could actually do, we throw money away on sending leaky microwave ovens into space. Worse, we get a bunch of people with no expertise in the area saying, effectively, "Hur, dur, you can't know it wont' work." Oh, and every time one of these mentions virtual particles, it reminds of a line from Idiocracy. "Duh. It has electrolytes." First you learn what a virtual particle is. No, not read about them in Wikipedia, but actually study some basic Field Theory to actually understand what it means. Then you can talk about them as if they explain something.

So you see, I hope, why I'm a bit uncomfortable comparing this to cold fusion. Cold fusion isn't impossible. Some very specific ideas about it are, but someone could, foreseeably, build a cold fusion reactor. Yeah, it will be some sort of "cheating" or other. Whether with a catalyst or some other trick. But there is nothing fundamentally wrong with fusion at room temperature, and so there could exist workarounds of the obstacles within the rules. This is not at all the same as someone suggesting that momentum could be not conserved, or get absorbed into something other than radiation, outflow, or environment. That's not working around the rules. It's pretending they don't exist for lack of knowing better.

Erm... Pardon the rant.

Edited February 20, 2015 by K^2

[Sean Mirrsen]

Any rule can be circumvented, and that's far from being the same.

Yay, another practitioner of the Rule of Exceptions! c:

[PB666]

You seem to be leaving out the fact that they show that the ATP synthase was neccessary for ATP synthesis.

Obviously, a good theory does not stand on one leg, however I should point out that if the mitochondria was not such an important ATP generator the reverse H+/ATPase might have been ignored. It goes without saying that many reactions do not reverse so easily many reverse reactions follow entirely different pathways. It was not an intuitive argument that everyone sat down and said 'Hey its the reverse of the proton pump reaction', for many scientist it took decades (as you kindly provided) of proofs to convince them, this was biochemistries version of the search for Higgs. When it was realized that the ETC was a big aspect of building a proton gradient, then big-picture questions started being asked.

I think this thread has reached its natural death point, it ceases to reveal anything new about VP or reaction mass 'disappearances'.

[Sean Mirrsen]

I think we just need more experimental data.

Can somebody hack the bank accounts of whatever lab runs the tests and dump some money on them?

[magnemoe]

I think we just need more experimental data.

Can somebody hack the bank accounts of whatever lab runs the tests and dump some money on them?

More tests are coming anyway, both to get more data and to scale it up past 100uN they need to move testing to another facility.

[perk]

Yay! You just invented pushing stuff with magnets! Have yourself a cookie. Also, realize that this limits interaction range for the same reason why you can't have two magnets interact from many kilometers apart, unless they are really large magnets.

Oh, and there isn't a "photon's point of view," even for real photons. A virtual photon isn't even following a null path. It can jump from A to B instantly, or take a year to travel one centimeter. All of these paths contribute to virtual particle exchanges.

The entirety of your knowledge seems to be picked up from popularized science shows and articles, and maybe a bit of Wikipedia. If you want to actually be able to talk about virtual particles, you need a course in Classical Mechanics, Electridynamics, Quantum Mechanics, Special Relativity, Introductory Particle Theory, and Introductory Quantum Field Theory. Typically takes about 3-4 years in college into the first year of Master's program. If you actually want to undertake this, I can point you at some books to start with.

But nothing's to stop you from turning ordinary atoms into muonic ones. That's kind of the point. There are loop-holes in just about everything that you might practically want to do. It's kind of what applied sciences are all about. The key is to distinguish understanding all of the rules, and knowing how to exploit them to achieve seemingly impossible goals, from charlatans or honestly misguided individuals who simply press on under a naive delusion that any rule can be broken. Any rule can be circumvented, and that's far from being the same.

Conservation of energy and momentum are the most fundamental principles we know. I'm prepared to discuss that with anyone who actually understands where these come from. If one doesn't understand Noether's Theorem, and one wishes to keep insisting that we can't possibly know for sure that these are fixed, one would be much wiser to just shut up. Trying to bet on any tech that violates these is beyond dumb. If we are deciding between funding that and alchemical search for philosopher's stone, it would be stupid not to invest in the stone.

But it's not the same thing as saying, "Here's your delta-V, good luck." There's a connection between 4-velocity and 4-momentum, but it can be nudged. In fact, that condition is always violated for virtual particles. They don't have to even be moving in the same direction as their momentum points. More usefully, it is violated by warp drives. FTL travel results in causality violations, and there's a pretty well-argumented conjecture in GR that suggests that it will always require exotic matter, which may or may not be possible to attain in any significant quantities. But on the other hand, no such restrictions exists for sub-light warp. I'm not aware of a viable configuration that allows sub-light warp without exotic matter, but at least that's on the table. There is nothing says that it doesn't exist. In fact, a lot of things suggest that it probably does. A good ion drive, a power supply, and a sub-light warp, and you can go anywhere in the Solar System within hours.

This is far beyond anything the EMDrive is promising, and it's very plausible. And here we are, instead of funding theoretical research into things we could actually do, we throw money away on sending leaky microwave ovens into space. Worse, we get a bunch of people with no expertise in the area saying, effectively, "Hur, dur, you can't know it wont' work." Oh, and every time one of these mentions virtual particles, it reminds of a line from Idiocracy. "Duh. It has electrolytes." First you learn what a virtual particle is. No, not read about them in Wikipedia, but actually study some basic Field Theory to actually understand what it means. Then you can talk about them as if they explain something.

So you see, I hope, why I'm a bit uncomfortable comparing this to cold fusion. Cold fusion isn't impossible. Some very specific ideas about it are, but someone could, foreseeably, build a cold fusion reactor. Yeah, it will be some sort of "cheating" or other. Whether with a catalyst or some other trick. But there is nothing fundamentally wrong with fusion at room temperature, and so there could exist workarounds of the obstacles within the rules. This is not at all the same as someone suggesting that momentum could be not conserved, or get absorbed into something other than radiation, outflow, or environment. That's not working around the rules. It's pretending they don't exist for lack of knowing better.

Erm... Pardon the rant.

I agree with most of what you write, especially that there is a difference between "cold" fusion in general and beating conservation laws.

I am not sure about a sublight warpdrive without exotic matter. The tenant of every warp solution is a region of relative expansion and relative contraction, (such that the bubble moves, no matter how fast), there you get from einsteins field equations a stress energy tensor for the expanding region that violates the strong energy condition, i.e. requires "exotic matter".

Can you clarify how that is on the table?

[N_las]

I am not sure about a sublight warpdrive without exotic matter. The tenant of every warp solution is a region of relative expansion and relative contraction, (such that the bubble moves, no matter how fast), there you get from einsteins field equations a stress energy tensor for the expanding region that violates the strong energy condition, i.e. requires "exotic matter".

Can you clarify how that is on the table?

I think sublight warpdrive is possible with only relative contraction, no expansion needed. But I know nothing.

[perk]

Well i just read a paper discussing the "necessity" of expansion or contraction, and it is possible to have no expansion of the volume elements, when the radial expansion (behind the bubble) is cancelled out by angular contractions (at the same point behind the bubble).. but in the general family of those solutions you still need regions that violate the strong energy condition to get the appropriate radial expansion

http://arxiv.org/pdf/gr-qc/0110086v3.pdf

Edited February 20, 2015 by perk

[PB666]

I think we just need more experimental data.

Can somebody hack the bank accounts of whatever lab runs the tests and dump some money on them?

Better yet give them a ride and a guidance system and lets see if their baby can reach an asteroid, maybe it can resurrect Philae off of 67P.

[Sean Mirrsen]

Better yet give them a ride and a guidance system and lets see if their baby can reach an asteroid, maybe it can resurrect Philae off of 67P.

Hehe, yeah. Practical science, the fastest kind of science! Also most interesting to follow.

It is, really, very disappointing, that such a trivial thing as money gets in the way of proper experimentation. How much does the whole thing weigh? How much would it cost to just punt it into LEO with the next SpaceX launch, then turn it on and see what happens?

How much more expensive would that be than all the other experiments that are going to be done on the poor device in the meantime?

[KerikBalm]

While I doubt this thing works, and I'm very skeptical...

Considering all the BS experiments* that get lofted to the ISS, it seems like it would be good to slap some solar panels on it, and give it a try

*maybe I'm being too harsh. I don't really follow in detail the biological experiments they do up there. I read something about a study of geckos mating in Zero G, which sounds ridiculous - but maybe its just the overly simplified explanation which lacks proper context, that gets repeated by/to the general public

Then there are all these "children's" experiments, where you hear about some elementary or high school having kids in a science class send something up -> I highly doubt there is any research worth the effort there; instead they do it for the propaganda value.

I'd also rather fund this effort, than more bombs and wars, or oil subsidies, or bailouts, or interest payments the USA shouldn't be making in the first place.

[SuperFastJellyfish]

Hehe, yeah. Practical science, the fastest kind of science! Also most interesting to follow.

It is, really, very disappointing, that such a trivial thing as money gets in the way of proper experimentation. How much does the whole thing weigh? How much would it cost to just punt it into LEO with the next SpaceX launch, then turn it on and see what happens?

How much more expensive would that be than all the other experiments that are going to be done on the poor device in the meantime?

I've linked this twice in this thread, but I'll do it again because there are people that obviously haven't seen it according to the questions being asked. An actual NASA employee(Paul March aka Star-Drive on the NSF forums) who is working with Dr. White has been giving technical information about their Eagleworks EM drive complete with pictures, math, and speculation. All of your questions will be answered if you skim through it.

I haven't read it today, but up until last night the most likely explanations for the thrust seemed to be thermal buckling, interactions with the vacuum chamber walls, or interactions with the testing apparatus.

[Sean Mirrsen]

I've linked this twice in this thread, but I'll do it again because there are people that obviously haven't seen it according to the questions being asked.

I've read that one, but it's very long, and mostly filled with technical and theoretical details. As far as I can remember, it doesn't answer the questions you quoted, besides maybe the weight of the assembly.

[SuperFastJellyfish]

I've read that one, but it's very long, and mostly filled with technical and theoretical details. As far as I can remember, it doesn't answer the questions you quoted, besides maybe the weight of the assembly.

It was more concerning the virtual particles discussion that really has no point to be in this thread, but, yes, it was the weight that I'm pretty sure Paul has said somewhere in one of those two threads. Not picking on you, or anything, you were just the last person to ask a question probably answered in by that link.

Edited February 20, 2015 by SuperFastJellyfish
speeling

[K^2]

I am not sure about a sublight warpdrive without exotic matter. The tenant of every warp solution is a region of relative expansion and relative contraction, (such that the bubble moves, no matter how fast), there you get from einsteins field equations a stress energy tensor for the expanding region that violates the strong energy condition, i.e. requires "exotic matter".

Can you clarify how that is on the table?

That is a gross over-simplification. You do not care about "expansion" and "contraction". That is not really how or why it works. Just another illustrative analogy that leads to bad intuition on the topic.

The key to the warp drive is the metric. It needs to have a "tilted" metric in the interior and flat in the exterior. What goes in the middle and constitutes a warp bubble is actually irrelevant for what it does. But it does fully determine your energy need. Further, non linear nature of EFEs means that structure in one location can affect energy needs of another. So it is hard to point to a specific feature and say that it will force negative energy requirement.

To demonstrate this a bit better, look at where energy is concentrated in Alcubierre Drive. Almost all of it is in the narrow band along the "equator" of the bubble, if we look at direction of motion as axis. And it goes to zero directly ahead and behind, where most of "expansion" and "contraction" takes place. Also, it is all negative. Both front and back of the "equator".

[Rakaydos]

You need something to pick up the recoil within range of the force. In vacuum, that means you need a force with an infinite range.

Or if you want an alternative way of thinking about it, the "propellant" is a stream of photons or gravitons. With strong nuclear force, you'd need to be producing a stream of free gluons, which isn't a thing^*. With weak force, you'd be producing Z bosons, and these have to decay into photons and neutrinos eventually. So again, you can't beat efficiency of a photon drive.

^* There is a theoretical edge case involving glue balls, but they'll have mass, so you'll be even worse off.

So, if virtual force carriers are eliminated as a working medium, what about the rest of the Standard Model?

What happens to a virtual Proton that was struck by a single real photon- not enough energy to turn it's virtual mass real?

[K^2]

You need to put in enough energy to produce a particle-antiparticle pair. That is a Lot of energy.

Otherwise, particle stays virtual, and must interact with something else.