Propellantless Field Propulsion and application

[kkattula]

I get the impression that "if it were a million times too small for any practical application" the validity of the demonstration would be endlessly debated by physicists. How do you prove that you've eliminated all sources of experimental error at that level, when it appears to violate conventional physics?

However, a practical and replicable demonstration would trigger the biggest shake-up in physics since relativity.

[KelvinZero]

I get the impression that "if it were a million times too small for any practical application" the validity of the demonstration would be endlessly debated by physicists. How do you prove that you've eliminated all sources of experimental error at that level, when it appears to violate conventional physics?

However, a practical and replicable demonstration would trigger the biggest shake-up in physics since relativity.

It certainly would

But in general nothing in advanced physics has to reach anything like a practical scale before it can be considered 99.99999% proven.

A physicist trying to prove this concept probably wouldnt build anything that remotely resembled a reactionless thruster. They would design an experiment where this affected a paremeter that we can measure extremely accurately. And some things we can measure extremely accurately.

[gospacex]

I assume that how much force it can generate is still open to debate, and even them are trying to discover precisely how much force they can get out of the device/effect.

The bigger (more important) question is "can it generate any force at all". This thread was started on NSF 2.5 years ago and the effect is still not demonstrated conclusively.

It appears there is a group of physicists who work on this and they seem to be convinced they see the effect in their experiment. The wider scientific community seem to be unimpressed. For some reason which eludes me, the physicists who work on this do not feel that they have to convincingly demonstrate the effect to physicists outside of their group.

With each passing year with no verified results, this whole story looks less and less credible overall. At least to me.

[hop]

I get the impression that "if it were a million times too small for any practical application" the validity of the demonstration would be endlessly debated by physicists. How do you prove that you've eliminated all sources of experimental error at that level, when it appears to violate conventional physics?

By doing having a convincing theoretical basis, doing good, repeatable science, and verifying multiple independent predictions. Look at the level things like the CMB anisotropy, neutrino measurements and dark matter searches have gone to. The sensitivity required to do those measurements is so far beyond the level of the claimed effects here it's not even funny.

[aceshigh]

@Hop: but then, those things were never scientific taboo...

I already said once to Star Drive, that I assume the best way for them to get their results accepted is to forget propellantless propulsion, even if its the most obvious application (and maybe better way to prove) of their mass fluctuations theories.

[Nathan]

More importantly - the EMDrive is coming on leaps and bounds. An experimental flight thruster has been built and this paper http://www.emdrive.com/Toulouse2010paper01.doc states that boeing is involved in building it's own thruster.

[markododa]

More importantly - the EMDrive is coming on leaps and bounds. An experimental flight thruster has been built and this paper http://www.emdrive.com/Toulouse2010paper01.doc states that boeing is involved in building it's own thruster.

it works with interaction with earths magnetic field?

[Sith]

More importantly - the EMDrive is coming on leaps and bounds. An experimental flight thruster has been built and this paper http://www.emdrive.com/Toulouse2010paper01.doc states that boeing is involved in building it's own thruster.

it works with interaction with earths magnetic field?

If you read the equations, you'll notice that they beat the famous Newtonian law F=-F with specific cone geometry. That's the whole secret of the machine if it works at all.

[aceshigh]

EM Drive? As far as I know it has already been debunked several times... unlike ME (Mach Effect) effect based thrusters.

Unlike Mach Effect, EM Drive violates conservation of energy. Although as reactionless drives, both may seem similar to the uncareful, the ME has a whole theoretical basis on a very poorly but important field of physics (the origins of inertia) to explain the effect and why it doesnt violates conservation of energy.

EM Drive on the other hand, has nothing of that. The system proposed by Shawyer is simple and DOES violate conservation of energy and analysic of it shows Shawyer simply cant get the equations right.

[cuddihy]

How do you prove that you've eliminated all sources of experimental error at that level, when it appears to violate conventional physics?

However, a practical and replicable demonstration would trigger the biggest shake-up in physics since relativity.

The effect described neither violates or overturns any conventional physics. What it would confirm is the origin of inertia as gravitational.

If it was sufficiently confirmed it would shake up physics all right, but not because of any new lines of theory but because it should have been found 30 years ago yet physicists have spent most of their energies on mathematical spurs like string theory to no practical effect for science or engineering.

[mlorrey]

I assume that how much force it can generate is still open to debate, and even them are trying to discover precisely how much force they can get out of the device/effect.

I think it all depends of how much mass differential they can create between the "pushed" and the "pulled" particles... and how fast they can "push" them.

Quite right. And the amount of force you can generate is largely dependent on the materials technology used, particularly in the capacitor dielectrics which have exhibited some significant degradation of thrust as they heat up, and heating up is a major consequence of such high frequency mechanical motion of the piezos that sandwich the capacitors, as well as the stress upon the material itself by the mass fluctuations of the particles in the dielectric. So there may be some significant practical limits for some time to come in the power density these things can operate at.

However, that doesn't make them impractical. ANY ability to extract any newtons from this thing unidirectionally for nothing but energy put in puts this technology way ahead of any other space drive since it wouldn't need to depend on a fuel source for propellant. Even accelerating at a mere 0.001 G in space without expending any fuel has IMMENSE practical value that would totally revolutionize interplanetary space travel.

For instance, a space probe leaving Earth's gravity field with a net velocity of a few thousand kph, weighing 100kg with 1kw in solar power capacity (not counting additional power for other systems on board) with ME thrusters generating 0.001 Newtons / Watt means it is generating 1 Newton of net thrust. 100kg = 980 Newtons, so you have a thrust to weight ratio of .00102 which means you can accelerate at a rate of .102 m/sec^2 at full power.

if V(0) = 0.55m/sec
then v(t) = 0.55m/sec + 0.102 m/sec^2*31536000 sec (the amount of time in 1 year)

v(t) = 3216672.55 m/sec or 3217 km/sec

aka 11,580,021 km/hour or a little more than 1% of the speed of light.

Enough for unmanned interstellar probes.

Of course, if the probes course during this year is directly out of the solar system or otherwise away from the Sun, its power capacity will dwindle as it moves away from the sun, so the actual speed will be significantly less. However if the power supply is a nuclear power source of some kind, like RTG's or betavoltaics, this speed could be attained, and exceeded as long as the isotopes produced power.

(if any of my math is off please correct, I'm always paranoid about decimal places)

[Nathan]

EM Drive? As far as I know it has already been debunked several times... unlike ME (Mach Effect) effect based thrusters.

Unlike Mach Effect, EM Drive violates conservation of energy. Although as reactionless drives, both may seem similar to the uncareful, the ME has a whole theoretical basis on a very poorly but important field of physics (the origins of inertia) to explain the effect and why it doesnt violates conservation of energy.

EM Drive on the other hand, has nothing of that. The system proposed by Shawyer is simple and DOES violate conservation of energy and analysic of it shows Shawyer simply cant get the equations right.

EM Drive has not been discredited. It doesn't violate any conservation law, in fact, it relies on them to work.
EM Drive is solid physics. Real money is being spent on them and even Boeing is involved. The thrusters actually work. They have limits that are set by conservation laws. Suggest all read the paper/s to understand.
The paper uses the analogy of an 'electromagnetic flywheel' to aid understanding.
ME Mass effect thrusters have not been debunked either - it's just hard to get any usable thrust at this early stage of development.
Both are still on the table as propulsion methods. Em-drive is a clear winner so far though.

[mlorrey]

EM Drive? As far as I know it has already been debunked several times... unlike ME (Mach Effect) effect based thrusters.

Unlike Mach Effect, EM Drive violates conservation of energy. Although as reactionless drives, both may seem similar to the uncareful, the ME has a whole theoretical basis on a very poorly but important field of physics (the origins of inertia) to explain the effect and why it doesnt violates conservation of energy.

EM Drive on the other hand, has nothing of that. The system proposed by Shawyer is simple and DOES violate conservation of energy and analysic of it shows Shawyer simply cant get the equations right.

EM Drive has not been discredited. It doesn't violate any conservation law, in fact, it relies on them to work.
EM Drive is solid physics. Real money is being spent on them and even Boeing is involved. The thrusters actually work. They have limits that are set by conservation laws. Suggest all read the paper/s to understand.
The paper uses the analogy of an 'electromagnetic flywheel' to aid understanding.
ME Mass effect thrusters have not been debunked either - it's just hard to get any usable thrust at this early stage of development.
Both are still on the table as propulsion methods. Em-drive is a clear winner so far though.

Got a URL to a BOEING web page that says they are involved? I've seen lots of startups claiming a lot of big corporate associations that are bogus.

[KelvinZero]

Sorry, that pretty much buries the EM drive.

With credible papers and demonstrable experiments, you would need a universal conspiracy of scientists to explain why it is not currently the hottest topic in the physics community today.

[aceshigh]

EM Drive has not been discredited. It doesn't violate any conservation law, in fact, it relies on them to work.
EM Drive is solid physics.

enlight me. Unless EM Drive IS TAKING SOMETHING from outside (even if its some sort of "spooky action at a distance") then its violating conservation of momentum law.

http://www.assassinationscience.com/johncostella/shawyerfraud.pdf

"...

Start with Shawyer’s Figure 2.4. He shows his truncated conical contraption, with a particle bounc-ing around inside it. It must have a constant energy, because it’s being reflected elastically at every wall. That means that the magnitude of its momentum, p, is constant.
As Shawyer correctly shows, the particle reflects off each wall in the way that you learnt at school (angle of incidence equals angle of reflection). But because the walls are inclined to the ‘axial’ di-rection (the axis going down the middle of the cone), this means that the angle that their momentum makes with the axial direction becomes ‘steeper’ at the narrow end of the cone, and ‘shallower’ at the bigger end of the cone. If you draw a few diagrams, and use some high school geometry, you can work out how much ‘steeper’ and ‘shallower’ the particle’s momentum angle gets, each time it bounces off a wall. Shawyer’s Figure 2.4 correctly shows this phenomenon.
Now look at the arrows below the diagram in Shawyer’s Figure 2.4. If you remember your high school physics, these are force vector arrows. They show the direction and strength of the force that the particle imparts on each wall as it hits it.
Shawyer’s F1 is the force on the ‘large’ end of the cone, and F2 is the force on the ‘small’ end of the cone. As he correctly shows, F1 is bigger than F2, because the particle’s momentum is much closer to ‘head on’ to the large end. (Remember, the size of the particle’s momentum does not change, only the direction it is heading in.)
After going through a few more trips into wave-land, Shawyer computes the difference between F1 and F2. That’s where his ‘drive’ comes from. All the complicated equations he throws in are just fluff around this basic result.
What’s wrong in Shawyer’s paper
Now we get to the point that a number of people have already made, but perhaps not confidently enough. Look at the arrows that Shawyer labels ‘Fs1’ and ‘Fs2’ on his Figure 2.4. These are sup-posed to be the forces that the particle imparts to the wall of the conical part of his contraption.
But hang on a minute! When a particle bounces elastically off a wall, doesn’t the wall feel a force that is perpendicular to the wall? Of course it does: if you remember your high school physics, you subtract the initial momentum vector from the final momentum vector, and the resultant force points into the wall. (OK, it’s actually called the ‘impulse’, not the force, but it’s effectively the same thing for what we’re talking about here).

Now look back at Shawyer’s Figure 2.4. He has Fs1 and Fs2 pointing perpendicular to the axial direction, not perpendicular to the cone’s walls.
His arrows are wrong.
This is the fundamental blunder that renders Shawyer’s paper meaningless. If you remember your high school physics, it is simple enough to draw a diagram to prove to yourself that, when a particle bounces off the wall of the cone, the increase in the particle’s momentum in the axial direction is exactly balanced by the impulse imparted to the cone in the opposite direction.
This is what has already been argued by those who have bothered to wade through Shawyer’s pa-per. It is not affected by all the ‘wave-land’ equations that Shawyer throws in. It is the fundamental error in his analysis.
So what do we really find out from this analysis, when we do it correctly? Simply this: when a par-ticle bounces around elastically inside a closed container, neither of them go anywhere. If you start in the right reference frame, then when the particle is moving left, the container is moving right; when the particle is moving up, the container is moving down; and so on. When the particle and the container collide, the directions of motion change, but their momenta still add up to zero. Nothing accelerates.
There is no ‘drive’."

Real money is being spent on them

to me, thats a big proof of fraud. When a company/person goes around asking for money to be poured in their experiments discredited by the physics community and that never stood peer-review. There are some other known examples...

ME guys at least are not in that for money, nor they want the publicity.

[aceshigh]

as for ME Effect, can someone (maybe StarDrive) comment on this section of the Wikipedia article on Woodward Effect
The hypothesis is also related to the Nordtvedt effect proposed by Kenneth L. Nordtvedt from Montana State University, who observed that some theories of gravity suggest that massive bodies should fall at different rates depending upon their gravitational self-energy. This would violate the strong equivalence principle  that the laws of gravitation are independent of velocity and location, a principle considered fundamental by many theoretical physicists.[14] The Lunar Laser Ranging Experiment has shown that if the Nordtvedt effect exists at all, it is extremely weak.

[gospacex]

ME Mass effect thrusters have not been debunked either - it's just hard to get any usable thrust at this early stage of development.

For zillionth time - at this point you do not need usable thrust! You need merely *detectable* thrust!

This will open up the field for many more people (and much more $$$) to look at the engineering problem of optimizing the technology and creating usable devices.

Until you have detectable thrust in an independently reproducible experiment, most people won't take you seriously.

[aceshigh]

For zillionth time - at this point you do not need usable thrust! You need merely *detectable* thrust!

This will open up the field for many more people (and much more $$$) to look at the engineering problem of optimizing the technology and creating usable devices.

Until you have detectable thrust in an independently reproducible experiment, most people won't take you seriously.

unless you are asking for money like Robert Shawyer does (and getting it from companies and even from government), you dont need to be taken seriously. You only need to work until you can prove your claims and be taken seriously. NO scientific theory should be taken seriously until its proven. Thats not specific only to reactionless thrusters. It should be for string theory, dark matter, boson higgs, etc, etc.

[gospacex]

For zillionth time - at this point you do not need usable thrust! You need merely *detectable* thrust!

This will open up the field for many more people (and much more $$$) to look at the engineering problem of optimizing the technology and creating usable devices.

Until you have detectable thrust in an independently reproducible experiment, most people won't take you seriously.

unless you are asking for money like Robert Shawyer does (and getting it from companies and even from government), you dont need to be taken seriously. You only need to work until you can prove your claims and be taken seriously.

Exactly what I'm saying. "You need to prove your claims". So far it is not done.

[Sith]

For instance, a space probe leaving Earth's gravity field with a net velocity of a few thousand kph, weighing 100kg with 1kw in solar power capacity (not counting additional power for other systems on board) with ME thrusters generating 0.001 Newtons / Watt means it is generating 1 Newton of net thrust. 100kg = 980 Newtons, so you have a thrust to weight ratio of .00102 which means you can accelerate at a rate of .102 m/sec^2 at full power.

if V(0) = 0.55m/sec
then v(t) = 0.55m/sec + 0.102 m/sec^2*31536000 sec (the amount of time in 1 year)

v(t) = 3216672.55 m/sec or 3217 km/sec

aka 11,580,021 km/hour or a little more than 1% of the speed of light.

I guess you use this formula to calculate it.