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[TCRS]

I need a simple video explaining me how this shit works.

fascinating though.

 

[Dynomutt]

So we doubt an American scientist and do not even give him an opportunity to display his concept. Chinese scientists say why not worst is it works and it does well. NASA sees this and bites his idea. I saw fuck don't share no more tech. So this is how we support our greatest minds.

Edit: British not American.

 

[Yrael]

Tbh, while i still don't think the thing actually work, i'm a bit perplexed at all the "it violate the conservation of momentum" crowd. I mean, there are already experiments which violate the conservation of momentum, the most famous being described by Fenyman in its book about eletromagnetism (17-4), as the disk with charged spheres that start spinning when you stop flowing current in its central solenoid . The solution to the paradox is that the momentum that is being "given" is the one lost by the field and as such give a total momentum to the material.
But if i can create such a field with simply currents and solenoids, this mean that we already accept that we just need electricity (movement of electrons) to create "real" momentum.
Now, why would it be so hard to believe that virtual electrons, created and destroyed constantly, may do the same in an hard vacuum? Casimir effects are very real, and already proved that "virtual" electrons can act on "real" matter.

Why would this be much different? If someone could explain where i'm going wrong, i'd be glad because it's bugging me.

EDIT: also technically, a laser pointer create thrust with just electricity, while being absurdly inefficient.

That example isn't a case of the conservation of momentum being violated, because the total momentum in the greater system (field + solenoid) is conserved. There are no experiments that violate the conservation of energy or linear/angular momentum.

Virtual (off-shell) particles, which are essentially mathematical constructs, are allowed to "appear" not to obey the conservation of momentum and energy because of the uncertainty principle - however, their measurable effects (ie. the Casimir force) do not violate the conservation of energy.

 

[bobbytkc]

So we doubt an American scientist and do not even give him an opportunity to display his concept. Chinese scientists say why not worst is it works and it does well. NASA sees this and bites his idea. I saw fuck don't share no more tech. So this is how we support our greatest minds.

Let's be fair. Scientists are frequently wring as well, and it is difficult to tell who is doing genuine science and who is not.

 

[mclem]

Aliens/time travellers have simply deemed us okay to travel further in the next ten years and so have unlocked the next layer of physics we can now access and manipulate.

 

[MJLord]

Let's be fair. Scientists are frequently wring as well, and it is difficult to tell who is doing genuine science and who is not.

Lets do more science!

 

[injurai]

Let's be fair. Scientists are frequently wring as well, and it is difficult to tell who is doing genuine science and who is not.

Science isn't a singular field. Not to mention the wealth of knowledge we have is immense, it's hard anymore to have a single person push a field. It's mostly teams and each individual is making mistakes. It's really not about who is and isn't doing genuine science, it's about the communities self-criticalness and peer review process.

 

[G.ZZZ]

That example isn't a case of the conservation of momentum being violated, because the total momentum in the greater system (field + solenoid) is conserved. There are no experiments that violate the conservation of energy or linear/angular momentum.

Virtual (off-shell) particles, which are essentially mathematical constructs, are allowed to "appear" not to obey the conservation of momentum and energy because of the uncertainty principle - however, their measurable effects (ie. the Casimir force) do not violate the conservation of energy.

Yeah my point was that we assume fields to be able to tranfer momentum to mass, and i didn't exactly grasp why it would have been a problem for a virtual field to do the same. Needless to say i realized shortly after some of the consequences of what a similar actually functioning drive would entail.

 

[EBCubs03]

Science should just be about getting the gist of how things work and haphazardly flinging millions of humans into space for no apparent reason

 

[eot]

I dont get you argument that nothing containing energy leaves the ship. An easy way out of this is the following . You can simply radiate heat outwards. Because radiation in all directions induces no net acceleration on the ship, it is not a propellant and does not contribute to the deceleration of the ship. This will explain the decreased rest mass of the ship. The fact that the engine produces heat coincides neatly with the 2nd law of thermodynamics.

Aha! But now you're contradicting yourself.
In the first example, where the ship is accelerating away from an observer you posited that the rest mass is being turned into kinetic energy and therefore total energy is conserved. In this reversed example (which is physically identical, just a different reference frame) you posit that the lost rest mass leaves the ship as heat. The two pictures are incompatible; if the ship spends its rest mass to radiate head, which as you said is an isotropic process (we can at least assume it to be) and doesn't accelerate the ship, then where does the kinetic energy come from in the first example?

There is also another problem, which is that the heat can't provide energy conservation in the first place. For example, let's say we have 1 J kinetic energy and 10 J rest mass. We spend 1 J to stop the ship, which radiates away. Now we have 9 J rest mass 1 J heat and we're missing 1 J. The kinetic energy still vanishes, because it's not transferred to anything because there's no reaction mass.

also,an argument based on acceleration will work for thrust as well. Thrust just induces time dependent acceleration, and you can always slice the time interval thin enough such that over each infinitesimally small time interval, acceleration is constant. Thats fundamental calculus. So i believe my arguments still make sense.

It's constant in each moment, but it's not equal in different moments. Since the acceleration is unbounded I can simply choose a point in time where the acceleration is sufficiently large to violate energy conservation.

 

[Vagabundo]

The thrust seems fairly low compared to something like Ion drives.

Still cool even if it doesn't work outside of Earth.

 

[Napoleonthechimp]

The thrust seems fairly low compared to something like Ion drives.

Still cool even if it doesn't work outside of Earth.

They've tested it in a vacuum, so wouldn't that mean it should work in space?

 

[The Elite]

They've tested it in a vacuum, so wouldn't that mean it should work in space?

That's what I thought as well.

 

[Sir_Crocodile]

They've tested it in a vacuum, so wouldn't that mean it should work in space?

Earth's magnetic field could be a factor I guess

 

[Osiris]

It's not known whether the test was performed in a vacuum at all yet, the project brief states:

"... within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure..."

Which suggests they have tested in a vacuum capable environment, but not actually in a vacuum yet.

There is no way to resolve the conflict of testing in a vacuum with he statement that it took place "at ambient atmospheric pressure" other than to accept that it hasn't yet been tested in a vacuum.

 

[DodgerSan]

Assuming this is true, the inventor will likely end up in Hibernity.

(+1 internet geek point if you get the reference).

 

[Vagabundo]

They've tested it in a vacuum, so wouldn't that mean it should work in space?

That's what I thought as well.

Since they don't really know how it works, no. A hard vacuum is not the same as inter planetary space.

Some speculation up thread about it pushing against the earth EM field.

Sending out a probe with one is probably the only sure way of testing it - unless they figure out exactly how it works.. Could probably do it fairly cheap too.

I doubt NASA will any time soon, maybe the Chinese. One of those mini nuclear reactors attached to this engine and have it zipping about the place after a while.

 

[TheContact]

Is this how the Event Horizon is created?

They need to remake that movie. Or another movie like it. Finding an as abandoned space ship and finding out what horrors happened on it is one of the coolest themes ever. Are any other movies like this? Ive watched Sunshine, Moon, Supernova, and Pandorum. Is interstellar any good? Similar to event horizon? Sorry for off topic

 

[DoDonGouki]

They need to remake that movie. Or another movie like it. Finding an as abandoned space ship and finding out what horrors happened on it is one of the coolest themes ever. Are any other movies like this? Ive watched Sunshine, Moon, Supernova, and Pandorum. Is interstellar any good? Similar to event horizon? Sorry for off topic

Definitely Sphere

 

[Nafai1123]

It's not known whether the test was performed in a vacuum at all yet, the project brief states:

"... within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure..."

Which suggests they have tested in a vacuum capable environment, but not actually in a vacuum yet.

There is no way to resolve the conflict of testing in a vacuum with he statement that it took place "at ambient atmospheric pressure" other than to accept that it hasn't yet been tested in a vacuum.

Are you reading that from the old project brief? The new one clearly states it was done in a hard vacuum.

 

[Gotchaye]

That's what I thought as well.

Earth's magnetic field could be a factor I guess

Right, this is a potential issue. You'd want to do an experiment where you rotate the entire apparatus rather than just reversing the engine.

Given that the device doesn't actually appear to be that involved - it seems to basically be an oddly-shaped microwave oven - before you go on to space testing you probably want to go ahead and build a really big one to make sure that the signal you're seeing is real. Strap a dozen of these together and run kilowatts through them and see if you get much more thrust.

If anyone spots any mistakes, please let me know, this was just a hasty calculation I did during my lunch break. However, I would expect the logarithmic time dependence to be correct even if there are errors since a rocket burning fuel has also has a velocity that scales with the natural logarithm of the mass. When accounting for the mass being lost due to energy expenditure, I would expect the velocity to scale similarly to a rocket losing mass from burning fuel.

I've not checked, but while this doesn't look unreasonable it's beside the point. The spacecraft's kinetic energy still increases much faster than its velocity (edit: momentum is probably the better quantity to use here) while it's using a constant amount of energy to generate thrust. Even if acceleration is non-constant, at high velocities a velocity change dV will produce a higher energy change dE than at low velocities. With a normal rocket, this works out because it's throwing mass out behind it, which from the perspective of a stationary observer has lost kinetic energy - the exhaust is moving more slowly than it was when it was fuel being carried inside the fast rocket. You need this reaction mass to not violate conservation laws. You need a way for the system to lose energy in order for this to work, and not "lose" in the sense of emitting heat - adding heat emission makes the problem even worse because now there's even more new energy in the universe.

 

[Effect]

This is amazing news. Especially if they can adapt it to an actual ship and significantly cut down travel time for the Moon, Mars, etc. Hell would it be possible for this to make escaping Earth's gravity easier? Or is that still a different problem and along a different technology line?

 

[Thursday War]

So, so far, this is holding up to scrutiny?

For reals?

you're gonna have to re-write halo :lol

 

[Jarmel]

Could this affect normal airline travel?

 

[Walshicus]

This is amazing news. Especially if they can adapt it to an actual ship and significantly cut down travel time for the Moon, Mars, etc. Hell would it be possible for this to make escaping Earth's gravity easier? Or is that still a different problem and along a different technology line?

This would have little overlap with actually getting things *into* space - that's still the domain of high-thrust rockets. This is about providing low but consistent thrust over long durations in order to achieve reduced journey times.

 

[The Elite]

Right, this is a potential issue. You'd want to do an experiment where you rotate the entire apparatus rather than just reversing the engine.

Given that the device doesn't actually appear to be that involved - it seems to basically be an oddly-shaped microwave oven - before you go on to space testing you probably want to go ahead and build a really big one to make sure that the signal you're seeing is real. Strap a dozen of these together and run kilowatts through them and see if you get much more thrust.



I've not checked, but while this doesn't look unreasonable it's beside the point. The spacecraft's kinetic energy still increases much faster than its velocity (edit: momentum is probably the better quantity to use here) while it's using a constant amount of energy to generate thrust. Even if acceleration is non-constant, at high velocities a velocity change dV will produce a higher energy change dE than at low velocities. With a normal rocket, this works out because it's throwing mass out behind it, which from the perspective of a stationary observer has lost kinetic energy - the exhaust is moving more slowly than it was when it was fuel being carried inside the fast rocket. You need this reaction mass to not violate conservation laws. You need a way for the system to lose energy in order for this to work, and not "lose" in the sense of emitting heat - adding heat emission makes the problem even worse because now there's even more new energy in the universe.

I didn't type that second quote.

Was it another me?

I'm panicking.

 

[Bear]

I've not checked, but while this doesn't look unreasonable it's beside the point. The spacecraft's kinetic energy still increases much faster than its velocity (edit: momentum is probably the better quantity to use here) while it's using a constant amount of energy to generate thrust. Even if acceleration is non-constant, at high velocities a velocity change dV will produce a higher energy change dE than at low velocities. With a normal rocket, this works out because it's throwing mass out behind it, which from the perspective of a stationary observer has lost kinetic energy - the exhaust is moving more slowly than it was when it was fuel being carried inside the fast rocket. You need this reaction mass to not violate conservation laws. You need a way for the system to lose energy in order for this to work, and not "lose" in the sense of emitting heat - adding heat emission makes the problem even worse because now there's even more new energy in the universe.

I'm not clear on why the mass of the stored energy doesn't satisfy that requirement, though. Since stored electromagnetic energy does contribute to the mass, why should the consumption of electricity be any different from a reaction mass in principle? The kinetic energy still increases with ln^2 like it would for a traditional engine due to that mass loss.

Perhaps I'm missing something here, but my point is that the ship will still lose mass, not that it is losing energy through heat emission.

 

[jellies_two]

I'm not clear on why the mass of the stored energy doesn't satisfy that requirement, though. Since stored electromagnetic energy does contribute to the mass, why should the consumption of electricity be any different from a reaction mass in principle? The kinetic energy still increases with ln^2 like it would for a traditional engine due to that mass loss.

Perhaps I'm missing something here, but my point is that the ship will still lose mass, not that it is losing energy through heat emission.

If you have a little nuclear power cell (atomic battery) producing power, like the one in Voyager, the mass loss from the radioactive decay of the material is negligible, and does not explain or offset anything.

 

[Slayer-33]

I didn't type that second quote.

Was it another me?

I'm panicking.

Wth? Word?

 

[Bear]

If you have a little nuclear power cell (atomic battery) producing power, like the one in Voyager, the mass loss from the radioactive decay of the material is negligible, and does not explain or offset anything.

Whether or not the mass loss is negligible depends on how much power you consume. When considering very high energy consumption, the mass isn't necessarily negligible.

It would require an immense amount of energy, however (about 18.75 TWh for every kg). Trying to plug my numbers into that would give an electromagnetic mass that is significantly smaller than the remaining mass, so it doesn't look like that approach will help explain the conservation of energy problem.

 

[Gotchaye]

I'm not clear on why the mass of the stored energy doesn't satisfy that requirement, though. Since stored electromagnetic energy does contribute to the mass, why should the consumption of electricity be any different from a reaction mass in principle? The kinetic energy still increases with ln^2 like it would for a traditional engine due to that mass loss.

Perhaps I'm missing something here, but my point is that the ship will still lose mass, not that it is losing energy through heat emission.

The easy way to see the problem with explanations like this is to try working them out in multiple reference frames.

Basically, suppose we put this engine on something and it's in steady operation, doing whatever it is it does in order to generate constant thrust. Consider what's going on from the perspective of an observer who's stationary with respect to the vehicle at some instant. Then consider what's going on from the perspective of an observer who's moving relative to the vehicle at some large but non-relativistic velocity.

The problem is this: they'll both see the momentum of the vehicle increase by the same amount over some period of time, but they'll measure different changes in the kinetic energy of the vehicle.

So you can't appeal to lost mass to explain where all this kinetic energy is coming from, because the amount of kinetic energy you need to explain depends on your reference frame. In a reference frame where the vehicle appears to be slowing down, it's losing kinetic energy. As long as we're talking about non-relativistic velocities, everybody's going to measure the same mass.

You can come up with a scheme that seems to conserve energy in a particular reference frame, but without some other mass being accelerated you're not going to conserve energy in almost all reference frames.

 

[FirewalkR]

Assuming this is true, the inventor will likely end up in Hibernity.

(+1 internet geek point if you get the reference).

I think those guys in the anti-grav suits are already on the way to grab him.

 

[Robot Carnival]

sorry to bump an old thread, but just curious, would this engine work for the space station? was asking in the other thread but nobody seems to have an answer. since the space station's funding is a huge problem, would this engine help with some of that? can it keep the ISS in orbit without too much cost?

 

[Fushin]

sorry to bump an old thread, but just curious, would this engine work for the space station? was asking in the other thread but nobody seems to have an answer. since the space station's funding is a huge problem, would this engine help with some of that? can it keep the ISS in orbit without too much cost?

It would be cheaper to fund the station than to fund the R&D of using this engine design on the ISS, building and shipping to the ISS, and installing on the ISS.

 

[Robot Carnival]

It would be cheaper to fund the station than to fund the R&D of using this engine design on the ISS, building and shipping to the ISS, and installing on the ISS.

ah, it's a shame then.

 

[Fushin]

ah, it's a shame then.

I'm cool with riding out our current ISS contract and then putting those funds toward a small lunar colony that practices technologies needed for sustaining a future Mars colony. As Buzz Aldrin says, "Get your ass to Mars!"

 

[cntr]

One of the interesting things about this is that it would become possible to destroy the Earth by accelerating an asteroid with this engine at near-light speeds and then slamming it into the planet.