Pop-scientist here, why wouldn't this reactionless warp-drive work? Assuming we can build a flywheel that can survive near light speed and have an onboard power storage that can spin it up to that speed it seems to be in full accord with Newton's laws. In case you can't read the text:
1) Telescoping link between capsules, they are free to move towards each other
2) Spherical flywheel in first capsule starts spinning. As it nears light speed from what I've heard about relativity it will start getting more massive instead of actually getting any faster
3) This mass will give it a stronger gravitational field right?
4) Both capsules now fall towards each other in accord with Newton's law of gravitation, however because the front capsule is now so much more massive it doesn't move noticeably as opposed to the rear capsule which basically blasts off towards the front capsule
5) After time, t the flywheel slows down, the masses of the two capsules becomes equal again, however the rear capsule stays in constant motion toward the front capsule because of Newton's first law
6) Once the capsule masses are equal the linkage is made to snap rigid which causes the rear capsule to transfer momentum to the front capsule
7) Because they are the same mass their new velocity is simply v/2 where v is the velocity gained by the rear capsule in it's initial gravitational acceleration
Thoughts? I say it's a warp drive because using my trusty pop-scientist's visualization of spacetime where it is a flat elastic sheet, the flywheel dents the sheet which sucks in the rear capsule but just before it gets there the dent disappears but then reappears later further down the line to repeat the process.
It could also work without the linkage simply bouncing into each other a la Newton's cradle. I don't see the momentum issue? If the rear capsule starts moving and hits the virtually stationary front capsule it will cause the front capsule to move, this is school tier stuff.
The basic trick here is you're varying the mass of the front capsule so that it's different during the moving-together phase vs. the moving-apart phase, right? That's where the momentum-nonconservation comes from.
The catch is that the capsule's overall mass won't vary like that. When the flywheel is spinning, its "extra" mass is due to all the kinetic energy you've pumped into it. But when it's not spinning, that energy has to be stashed somewhere— super-batteries, antimatter bottle, whatever—and it will still have a gravitational field when it's in that other form, as well. You're converting mass-energy back and forth between different forms inside the capsule but all those forms should have the same gravity.
Nice concept, though, even if it has that fatal flaw. I don't think I've seen this idea for a perpetual-motion / reactionless-drive before.
If you have a machine that can accelerate without having an exhaust of some kind, then you violate basic physics as we understand it, and the machine almost certainly would not work.
A machine that can accelerate without having exhaust is often called a "reactionless drive". And they don't exist, just like perpetual motion machines.
There's no contradiction to momentum.
First, if you speed up the flywheel to such a high speed and the other thing moves negligibly, you have to be kidding when you say you can slow it down and let their masses be equal. Just think about what you're doing. You want it to be lighter than the other side at first, then reduce its mass such that they have the same mass. Not gonna work.
There is no way this could work.
>When the flywheel is spinning, its "extra" mass is due to all the kinetic energy you've pumped into it. But when it's not spinning, that energy has to be stashed somewhere— super-batteries, antimatter bottle, whatever—and it will still have a gravitational field when it's in that other form, as well. You're converting mass-energy back and forth between different forms inside the capsule but all those forms should have the same gravity.
This makes sense but I I thought only K.E led to relativistic mass gain? If you dissipate the flywheel energy as heat how does heat create a gravitational field?
Thanks, It just came to me while I was lying in bed so I thought why not talk about it?
The Alcubierre drive has no exhaust and doesn't violate physics.
Forget the engineering feasibility, we all know it's not gonna happen I'm talking does it break laws of physics?
a2 is really really small. it's like if a planet appeared in front of you, you fall towards it and the planet falls toward you, we all know this. However the speed of the planet toward you can be ignored because it's so small so all an observer sees is you falling toward a "stationary" planet. You're right if the planet kept the same mass then the net momentum would cancel but it doesn't so the momentum is imbalanced unless anyone can decisively prove this line of reasoning wrong
There is no lightspeed, only near lightspeed. At no point does any part of the system ever exceed the speed of light.
>You're not answering the question. He could've easily used wireless transmission like solar panels or some shit.
>And as this guy >>7643573 I could dodge that by transmitting and removing the power wirelessly
You're going to be accelerating relative to your energy store. As you move away from your energy store, your transmission will be become more and more red-shifted and contain less and less of the original energy.
Maybe this could even work practically since amount of thrust doesn't matter much in frictionless space only duration. How fast do you have to spin something to get even a micronewton gravitational field increase?
to OP and all the other faggets in this thread
you're so full of shit, the sole fact that you're actually using a whiteboard to play scientist and write crap theories reflect the pile of shit you are
seriously what is wrong with you dumbass ? do you seriously think mixing high school tier mechanics with shitty understanding of dumbed down theories would work ?
everything in what you wrote is shit, there is no objection to have, it's like having a retard drawing a potato on a whiteboard an calling it a theory
Ok so this isn't a warp drive in the usual FTL sense then? Just a potentially fast ship that would use batteries of some kind to spin the flywheel?
I don't exactly see why it wouldn't work but I also don't really see how its a big deal. I mean faster space travel would be nice but if it ain't FTL (which I'm not saying is possible, I think its almost certainly impossible) its not gonna be like Star Trek I mean your not gonna just zip around to far away planets with this thing its still a hell of a long trip even at near light speed, well you could make the trip at near light speed actually but everyone you knew on Earth would be long dead.
HAAHA /sci/ is seriously attacking me for using a whiteboard? is it a sacred object that can only be touched by those with 12 PhDs? I just dont even know what to say to this...
And i came here asking you to disprove it, i never claimed it to be true, i openly admitted being a popscientist who doesnt know relativity. Im saying if /sci/ cant disprove it then i take it to stackexchange and in the unlikely scenario they cant disprove it either then maybe its time to tell nasa
Using a whiteboard is playing scientist haha oh wow still laughing about that one
>still no disproof
How hard is it to say "It is extremely unlikely to work but I don't myself know enough relativity to conclusively disprove it so ask someone more knowledgeable"? Ad hominems just prove you have nothing more intelligent to say.
The thing you need to take into account for relativistic speeds is the gamma factor for your momentum. Even then, one could easily find an expression for the relativistic momentum as
pc = sqrt(E^2 - m^2c^4)
As you try to approach near light speed c, your energy term needs to drastically increase to match, which is something that is not achievable as the energy required to approach even half of light speed is tremendous.
>I thought only K.E led to relativistic mass gain?
All kinds of mass-energy lead to mass gain. K.E., atomic bonds, chemical bonds, deformation energy in springs, EM fields. They all produce a gravitational field.
> I could dodge that by transmitting and removing the power wirelessly
What these anons said: >>7643659 >>7644098 you basically have a solar sail with a flywheel on it. The redshift in the wireless power transmission sucks all of the fun out of it.
>As it nears light speed from what I've heard about relativity it will start getting more massive instead of actually getting any faster
This is wrong. Mass is an invariant, or at least should be. The idea of relativistic mass is a cancer that Einstein specifically spoke out against. You should only focus on a bodies dynamical (so momentum and energy) quantities when studying it's motion, moreover since this is about gravitation you should be using General relativity and not some hybrid of SR and Newtonian mechanics.
Split it into two counter-rotating flywheels, problem solved
>Told for years that near light speed causes mass increase
>Use it to design thought experiment
>"near light speed doesn't cause mass increase"
If you insist on keeping science an elitist secret club how can you complain about all the pop-sci theories out there like my one? Why don't you guys tell the truth about what happens instead of dumbing it down to the point where it's basically not true?
So explain, no bullshit, what really happens as a mass approaches light speed?
>Why don't you guys tell the truth about what happens instead of dumbing it down to the point where it's basically not true?
because it turns out that modelling reality is quite complicated but people want easy analogies so they can pretend to understand stuff.
>solve this complex system for me for no other reason than my own satisfaction
Yeah, no. Lrn2 relativistic mechanics and do it yourself.
Nice idea, more original then most, but still got some issues.
Let's say you got a huge battery that powers your flywheel. The problem is that E=M (or more historically derived E=Mc^2). The energy in the batteries has mass, and that mass will be equal to the mass gained by the flywheel assuming 100% efficiency. If that is the case then you are just effectively changing the mass from electrical energy to kinetic mass, but the total system has not changed thus no net movement.
Putting the battery on the other part of the ship doesn't help. You would get net movement during the first part as the ship moves opposite the flow of electrical energy. It odd thinking equal and opposite reaction from moving electrons in a wire, but electrons have mass and are moving down the wire so the wire will move opposite with equal force. But electrons move surprisingly slowly and have little mass compared to the ship. Interestingly the energy from the electromagnetic field moves much faster and has an effect, think phonons which are like photons, but the mass is a lot smaller so it does even less. But when you absorb the energy back into the battery from the flywheel the effect will be reversed. So the ship would lurch forward a little then lurch back, with not net movement, same with all reactionless drives
Now if you collected the energy from outside the ship, say solar panels, then yes it would work. In fact you could get even more efficiency by dumping the heat in one direction to get thrust from the infrared photons. But your thrust would not exceed the reactionary mass of the photons you collected. At that point you have a complex reactionary thruster that uses photons. Problem with such a system is it would be very complex and have such a small amount of thrust that a toy rocket would beat it hands down, unless you planned to leave this thing running for a very very very very long time.
A nuclear powered ion drive would be a far better investment.
So it does technically work but it's not reactionless because it needs incoming photons which would be better used just bouncing off a mirror? Thanks for the explanation. I'm still proud of myself, a working "warp-drive" on the first try. However I've asked some other people and they got into a long debate over whether relativistic mass even creates a gravitational field in the first place. So meme drive 2 still hangs in the balance I'm afraid
In the world of physics engineering doesn't exist. It's a beautiful world with massless beams, non-exploding flywheels and no god-damn air resistance.
If you want the truth then maybe you should complete a degree in physics. There's a reason that people study it - it takes a long time to understand. If it could be learnt by reading things on the internet, then everyone would be an expert.
It is silly and vastly impractical, but it would travel through space assuming the typical hypothetical extremes like indestructible flywheel and solar panels that collect the huge amount of energy to have a noticeable effect. A mirror sail would be far more effective.
That said I am reluctant to call it a warp drive. The local space of the flywheel would warp do to relativistic spinning which starts to get noticeable around 0.7 ~ 0.9 c depending on the equation setup, but the whole ship would not. So you would not get the effects that warp drives offer, which means your trip will still take longer then your lifetime to get anywhere, probably a lot longer given how slow this would be without some insanely massive energy input. Also this will top out at 0.999... c and no faster as the warp conditions needed to go faster then light are not present in this as I understand it.
Yes, a relativistic mass creates a gravitational field. If it didn't then it would be a lot easier to go faster then the speed of light. As the added mass of going faster mean more energy is needed to go faster which makes the mass increases and so on. That is why the speed of light is the top speed limit.
Warp drives go faster only because the space around it goes faster so they never violate this rule technically. (this pic really helps explains what makes warp drives special and why the amount of time often equalizes in a manner that doesn't kill someone)
Of course there are many types of FTL drives, but most involve warping space-time. But the name warp drive is normally reserved for the Alcubierre style warp drive, which hypothetically needs a way to make both gravity and negative/anti gravity (often from negative energy which is a touchy topic). After all don't want to confuse it with a wormhole or jump dive or hyper drive or some other version of a warp drive.
Glad to help.
Yea him calling it a warp drive is a little miss leading since people think FTL when they hear warp drive and this not FTL.
That said your "longer than your lifespan" statement isn't necessarily correct. At near light speed a person could travel to a far away solar system within their life span thanks to time dilation. Everyone you knew on Earth would be long dead though, for all practical purposes it would be a 1 way trip.
If this ship would still be significantly slower than light though then yea its not gonna get you outside the solar system any time soon.
Well this is still the only "warp-drive" I've ever seen that werks without invoking any speculative physics. Shame it's useless. And yeah I think it is a warp drive because it's like saying the Brayton cycle isn't a hot air engine because it doesn't work like the Otto cycle. It may not heat the air in the same way but it still heats it.
While I do acknowledge the time dilatation would let the crew live long enough to make there trip. That assumes the ship gets to a decent time dilatation speed before they age too much. I don't see the acceleration getting that high even if the top velocity is just under light speed.
Fine, as long as you understand why I won't call it a warp drive despite the fact there is a warping effect present in the drive system. Or at least name it _____ warp drive to prevent confusion.
Also I remembered you will want two flywheels to balance the rotation effects.
> why wouldn't this reactionless warp-drive work?
That's why it wouldn't work.
That's a fair point. You'd have to have the means to accelerate to near C quickly so you don't age too much then but also not so quickly you die from the g forces. Maybe it can't be done.
If the principle of OP's drive is sound (which by the looks of it might not be true), then would this be a simpler refinement of it? You've got a large disc with a central hole in it, and a capsule with your passengers at some distance from it. The disc is spun up to near lightspeed, increasing its mass and creating a gravitational field, which draws the capsule towards it. The capsule passes through the central hole at great(?) speed, at which point the disc is stopped from turning. The capsule then coasts to its destination. The same process could happen in reverse at the destination.
Does this idea have any merit, at all?
>at which point the disc is stopped from turning.
Unless you do this instantly, there would be no appreciable effect. The faster you slow down that flywheel the more force is required, and unless there's 100% efficiency that force would be better used just hitting the pod itself.
Yeah, this idea and the OP's are retarded from an engineering perspective even if such things were possible to construct - it was more a question about theoretical possibility rather than practicality.
I have not gotten into more detail analyses, but the more serious discussion I have been in make it sound like it would take a few years. Factor in second half of the trip slowing down (very important) and most hypothetical trips sound like 10 ~ 15 years give or take for crew. One interesting thing I noticed is the time it takes on the crew decreases with longer trips. So traveling half way across the galaxy takes lets say 10 years but traveling to another galaxy takes only 12 years. (number made up to show pattern, not to scale or reference)
If somebody wanted to actually do the math we can model the ship at 9.8m/s of acceleration and plug in test points to get a nice graph. But we would need to know the distance of the trip to solve. Also be nice to know how much outside time passes. Really sucks if you get to the planet only to find the local star went nova few days after you left.
Well in my list of FTL systems I called it an "Inch drive, because it made me think of an inch worm, but I will have the records changed to "WE drive" and attributed to Anonymous of /sci/ till someone can make a better sounding name, even then you still keep developer rights under the attributed section.
Can't speak for others like >>7650083 and >>7643462 (OP), but yes discussing this is fun and educational. Yes, some declared assumptions are unrealistic but they are declared so that does not make them shitposting.
Look at >>7650083 as a good example.
They ask a legitimate question, which sound silly but is actually very insightful. From it we can answer that yes the disc's rotation creates an increase in the gravity field (relativistic speed effects). The higher gravity field would pull the ship forward and also move the disc backwards (action-reaction force pairs).
And if the disc were to suddenly stop right before the ship reach a certain point, which is actually not the center of gravity of the disc as any mass passed will work against it. So we want the disc to be thinner to get more distance for acceleration (geometry). The gravity field would drop and the ship would have gained speed from the setup, as would the disc in the opposite direction. This is very similar to a gravitational slingshot setup (orbital mechanics).
A reverse setup is a little more involved as gravity only pulls one direction. So you would need to have a disc suddenly rotate near the speed of light after the ship passed a point so the gravity would pull against it.
Sure suddenly rotating a disc to near the speed of light is certainly not practical in any realistic construction, but it does help us better understand the physic involved even if some assumptions are not feasible.
In addition the g-force on the ship is also effected by the geometry of the setup, don't want the ship accelerating too fast. A series of discs with proper spacing would behave more like a gauss gun using gravity instead of magnetic forces.
Asking hypothetical setups that is a core part of science. Many great insights are found this way.
This is not shitposting.
OP and esteemed inventor of the WE Drive here, I like it. Only thing is it's one shot only. Nonetheless excellent idea, why didnt I think of this?
How will you get across a galaxy in 12 years? The WE Drive does not have FTL capability.
Why are you hating? This is physics, we do hypothetical thought experiments, it doesnt have to be realistic so long as it doesnt break any laws of physics and this does not.
read the thread. If you have it onboard as originally intended it wont work just as you say, however some anons said that if you beam the mass-energy in it will work but will be utterly pointless because you may as well just bounce the photons off of a sail.
First, 12 years was "(number made up to show pattern, not to scale or reference)" so don't use it so literally.
The idea is the longer you acceleration the higher velocity you have. The higher velocity you have the more temporal dilation effects take place. So the time the crew experiences still incenses but at a decreasing rate the longer the distance traveled, if acceleration is constant. Might help to read about the twin paradox for more details.
This is why if the crew traveled at the speed of light they would not experience any time loss, to them it would be basically instantaneous regardless of distance. That said the rest of the universe would still have time pass normally so from the other perspective they may have took a long time to travel there.
It is like some weird economy of scale for interstellar travel. For just a little bit longer wait your crew can travel much farther.
Wouldn't the effectiveness of drive decrease as the ship gains speed due to the increased gravity of the non-flywheel components, and that the fly wheel will no longer be able to travel significantly faster than the other components because it is already translating at some fraction of c? In other words as the speed of the ship increases, the relative gravitational delta due to the fly wheel starting and stopping will decrease.
Reading this in more detail this time.
It'll totally work. It's also highly inefficient. It sounds like you're just letting the flywheel spin down, which means the energy is converted to heat, which means that the heat will be radiated outwards as (black body) radiation in all directions.
Remember earlier when I said that exhaust-less space-propulsion cannot work? Light is a form of exhaust. You could take a literal block of iron and attach a flashlight to it. The light coming out of the flashlight and going into space is a form of exhaust. Light has momentum. A ridiculously small amount of momentum, but it has momentum. If you attach a light to that block iron and turn on the flashlight, the block of iron will accelerate in the direction opposite of the beam of light. The light is exhaust.
Without an external source of power, the energy of the flywheel is converted to heat, which is converted to (black body) radiation, which is presumably roughly equal in all directions (you didn't specify the particulars of the shape of your shapeship).
Without that external energy source, spinning up the flywheel doesn't involve gaining or losing energy nor momentum in your spaceship, and thus the center of mass&energy remains unchanged.
With an external source of energy, presumably via EMR, that impacts momentum, and you'll need to take that into account. Aka a solar sail.
You totally have exhaust in the sense that matters for conversation of momentum - light itself.
Different guy here, but there's one thing that always bugged me about time dilation. Maybe someone can clear it up for me.
Time dilation is supposedly velocity-dependent, but velocity itself is reference-frame dependent. Who's to say which twin is "moving" and which is "at rest?"
There isn't an absolute way of looking at it but one moved relative to the other and comes back younger than the other.
Could another observer say they were at rest relative to one another? Maybe but the one twin changed directions during his trip, they would notice that.
OP here, the apple gained potential by being pushed upwards by the tree which exhausted O2 to do it. What you say is like saying a catapult is reactionless because the stone "just moves" when you let go. You had to pull it back before you let it go remember.