i think the idea is that since a capacitor can store energy in the electric field between it’s plates, then due to mass-energy equivalence it must also gain mass if it is storing energy. it’s not so much that the electrons add mass to the capacitor as much as the presence of the E field implies some extra mass under relativity.
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Probably correct but it is worthwile to repeat the experiment if there is a tiny possibility that there is a new effect and hunting down experimental errors is also a good exercise.
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[quote=“joeblough, post:61, topic:46850, full:true”]
due to mass-energy equivalence it must also gain mass if it is storing energy.[/quote]
Yup, this is bog standard special relativity physics. The energy store being used to charge and discharge the capacitor will also be changing mass, and there will be a momentum associated with moving energy between the two. You’ll end up with momentum being conserved and the thruster not going anywhere.
My guess as to what is going on is that there are stray EM fields from the thruster coupling to the environment, making the room the reaction mass.
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Yes, I got that after reading the Woodward effect description. This isn’t quite explained in the main article.
I still have reservations about whether this effect, even if it is real, would result in a net motion in one direction. Perhaps it works… perhaps not. A different group of people working on replication would be informative.
yeah i agree, no idea if it really works, but at least the “changing mass” part should work. of course as @mscibing points out above the energy/momentum transfer would net out to 0.
Ah, the Michaelson-Morley experiment!
It turns out it’s impossible to measure the earth’s motion relative to an absolute reference frame, such as the hypothetical luminiferous ether. It would probably be impossible to measure the only object in the universe’s motion relative to an absolute reference frame, too.
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Also, Mach 1 is not “the speed of sound at sea level.” It is the local speed of sound wherever you are measuring it. That’s why a Mach number is so useful, as opposed to a speed in MPH or KPH.
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In the future this may put me into the category of the original flat-earthers that we laugh at today, but I am instinctively skeptical about experimental energy (or motive) sources that require “extremely sensitive” instruments to detect.
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I can see why you have that in mind, but I was not referring to an absolute reference frame. Just the idea that there are some reference frames in which velocity (as a 4-vector) could be defined. It will look different in the various reference frames. Despite that, the Lorentz inner product of that vector with itself remains constant. Hence my comment about photons.
However, what I was really trying to say was that velocity (as a 4-vector) is a fundamental part of our universe. If we want to talk about a universe which obeys the same laws as ours except that it has a single particle, we shouldn’t be too fast to throw things away because they are unobservable in that universe — we already know that those laws depend on motion even if that fact is internally unobservable.
If there’s only a single indivisible object in the universe, who or what is doing the measurement of it?
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Strange thrust: the unproven science that could propel our children into space
Whoa whoa WHOA! We all have our breaking point but I think you might just need a little “me” time.
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“Or is it?”
It is.
Momentum conservation forbids a reactionless drive and momentum conservation follows from translational symmetry (i.e. the laws of physics are the same over here as they are over there).
This has been another edition of short answers to stupid questions.
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If I had to choose something to be triggered into centuries’ reverie between dental hygenists and lead brick vibration isolation (it’s not effective,) it’s definitely going to be the second bit. Fun article in encouragement of light criticism, here! How much better than showing off a 22 ton refrigeration system and asking how long before the building’s either on the moon or out of air, we shall see.
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For completeness, he should run another control experiment where thrust is perpendicular to the previous tests. Maybe it only works in the two opposite alignments? But I’m sure he already tried that too.
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Dean Drive redux.
Charles, Keith Henson here. I have no problem with reactionless drives, but they do have interesting consequences.
Any drive that turns power into velocity independent force generates unlimited free energy.
Easy thought experiment, put one on a frictionless skateboard in a vacuum. It will accelerate as long as it has power. When it gets to a high enough speed, lower a wheel connected to a generator that makes more power than the drive needs. Tap it and supply the whole world.
If someone can get a reactionless drive to work, they solve more than a transport problem.
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I actually did try to write a novel. I even published it. It was rubbish of course. It’s my firm opinion that writing a good novel, a really good one that pushes forward the boundaries of literature is very very hard. Only a handful of people are actually capable of doing it. I guess that that is why we have a Nobel prize for Literature along with one for Chemistry and Physics. Making a good film or even a good video game is really really hard.
The only big difference between science and arts is that science tends to have hard criteria for judging the quality of work. It is possible to write a novel that is not universally pushing the limits of literature, but that certain audience finds entertaining, inspiring or enlightening. Many people seem to be entirely happy with this achievement. In the world of science this is equivalent to publishing a paper that does not really contribute very much towards a solution to some big problem in any given field, rather the one that makes a small step towards some larger goal. For some reason people, me included, seem to find this way less satisfying.
In my time I had plenty of uninspiring lecturers and a very few inspiring ones, but don’t blame the system for shortfalls of individuals. I get where you are coming from, quite often I was frustrated by complex math theory. It seemed so dry and inaccessible. I was always thinking that if only it was presented better, if only I knew what the purpose or use behind a particular math apparatus was, that I would understand it better. But than again, what was hard for me was easy for the next guy. Boy did that hurt. Problem after all must have been in me, as other guys seemed to absorb this stuff without breaking a sweat.
There is this notion that science would be easier if we kicked the maths out, or if it was explained somehow differently. That it is hard because lecturers make it sound hard, or because they explain it in a long way. Yes, in many cases quality of lectures can be improved. People that are good at science are not always good at explaining science to others. Some are. Some are not. Still, we need theory not because we like to solve puzzles, but because it help us solve practical problems. It is the quickest way really.
There is this apocrypha about Tesla’s time at Edison’s lab. Tesla had very good formal education. Edison did not. Edison and his assistants had spent hundreds of hours experimenting with various materials trying to find a suitable fiber for the lighting bulbs. Tesla walked in, wrote a couple of equations that relate electromagnetic resistance and heat dissipation and here we are still using wolfram for the purpose.
Theory gives us the framework to build practical things. Theory must have predictive qualities. Periodic system of elements is a classical example of this. Mendeleev come up with a theoretic way how to organize the elements according to their atomic weights. There were couple of holes in his table, but the system was theoretically valid. He said look guys, of all of these elements that we have discovered, we must have skipped a few. Go look for something heavier than Silicon and lighter than Tin. It should have atomic weight of about 72. And lo and behold Germanium was discovered.
There are ways to do science if you skip formal education. Lectures could be made simpler and more understandable. Still real meaningful science will always be hard. However, this doesn’t mean other areas of human endeavor are not as hard.
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The electronics necessary to make something vibrate quickly is quite new. It is used in electronic accelerometers and it is the most important thing, that lets cheap us making drones, so I am not surprised, that nobody tried it before.
When I read this, my first thought was this: if I change mass of one of the boxes, the center of mass changes, so it is likely, that both of the boxes move and the whole effect is negated. I can see, that you had the same thought.
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The idea is to accelerate a small object while varying its energy. For
example, if the small object is a capacitor that is vibrating at a
relatively high frequency, and the electrical charge on it fluctuates at
twice that frequency, the mass of the capacitor should fluctuate, too
But mass-energy is conserved in this situation, so inertia remains the same.
This is so over my head. I’ll have to admit that even assuming you can jiggle and poke an object’s mass into changing a little bit for a little while, I ended the article without the slightest idea of how this would make an object move in space. The box push-pull example made sense, but kind of depends on a ground-friction-and-gravity context, doesn’t it?
And to scale this into spaceship speeds?You geniuses figure this out, I’m hopeless.
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