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EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way (ibtimes.co.uk)
An anonymous reader quotes a report from International Business Times UK: An independent scientist has confirmed that the paper by scientists at the NASA Eagleworks Laboratories on achieving thrust using highly controversial space propulsion technology EmDrive has passed peer review, and will soon be published by the American Institute of Aeronautics and Astronautics (AIAA). Dr Jose Rodal posted on the NASA Spaceflight forum -- in a now-deleted comment -- that the new paper will be entitled "Measurement of Impulsive Thrust from a Closed Radio Frequency Cavity in Vacuum" and is authored by "Harold White, Paul March, Lawrence, Vera, Sylvester, Brady and Bailey." Rodal also revealed that the paper will be published in the AIAA Journal of Propulsion and Power, a prominent journal published by the AIAA, which is one of the world's largest technical societies dedicated to aerospace innovations. Although Eagleworks engineer Paul March has posted several updates on the ongoing research to the NASA Spaceflight forum showing that repeated tests conducted on the EmDrive in a vacuum successfully yielded thrust results that could not be explained by external interference, those in the international scientific community who doubt the feasibility of the technology have long believed real results of thrust by Eagleworks would never see the light of day.
Who are "Lawrence, Vera, Sylvester, Brady and Bailey"? Their cats?
Reviw is sooooo important....
-- Make America hate again!
EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way
But we're not sure how long it'll take because we're not sure it puts out any thrust.
systemd is Roko's Basilisk.
That's all? I'm fully prepared for the Armored Space Nutter division to come out in full force waving their Star Trek box sets and preparing their trip to Andromeda.
Never give up! Never surrender!
That's all? I'm fully prepared for the Armored Space Nutter division to come out in full force waving their Star Trek box sets and preparing their trip to Andromeda.
In the meantime, you're filling in nicely for them.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
How does the energy efficiency of this drive compare to a normal rocket?
If it works as advertised, it violates the law of conservation of energy, so its energy efficiency can be infinite.
(it produces a force with no reaction mass. Since energy is 1/2 mV^2, power is force times velocity, and thus the change in energy (per unit time) is proportional to velocity. So, if it runs at a given power level to produce a given thrust level, you can get more energy out than you put in simply be starting out in motion.)
Could this allow interstellar travel, by humans, within a normal human lifespan? What kind of reletavistic effects happen at high speed? I would assume thrust would drop as you approach C.
Well, if it violates the theory of relativity, anything could happen, I guess. Right now the thrust level quoted is micronewtons, so it would take millions of years to get up to the speed of light. But if the machine works, even at all, all bets on physics are off.
http://www.geoffreylandis.com
The efficiency is very low. Read TFA: "[...] the system is consistently performing with a thrust to power ratio of 1.2 +/- 0.1 mN/Kw ()".
According to TFA, however, they are working on a far more efficient design.
This is your sig. There are thousands more, but this one is yours.
For me, even when there seemed to be some effect, it was simply far, far too small. Well within experimental noise - and certainly nothing you're going to propel anything anywhere with.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
I imagine that there will be replicability tests. It's possible, but not certain, that we may have found Clarke's "space drive", a drive requiring no reaction mass. On the other hand, so many of these things have fizzled, I'm remaining VERY cautiously optimistic.
The trouble is that the thrust is so low that measuring it reliably is so hard that nobody knows if there is thrust at all or just measurement problems. It's said to be about 1mN/kW, much lower than even an ion drive.
I think there is just noise and no signal and people are seeing a rabbit in the clouds because they're looking for it very hard.
Well within experimental noise - and certainly nothing you're going to propel anything anywhere with.
I agree I'm still far from sold on the EM drive. I want to see it working in a vacuum, away from earth's magnetic field, and I want an explanation for the physics behind it. But if there's new physics, then who can say what the eventual application will be? Our first experiments with radioactive materials made things a little warm and glowy (and poisonous) but then fast forward a few decades and we've got mushroom clouds and nuclear reactors.
We don't have a state-run media we have a media-run state.
Well, if it violates the theory of relativity, anything could happen, I guess.
The guy ("scientist"?), Roger Shawyer, who invented it claims that it's actually due to the theory of relativity that it works.
Yes, but their test results explicitly falsified that theory. They tested this. The device (was claimed to) produce thrust whether or not it had the asymmetry that Shawyer claimed was required by his theory
...I'm not a physicist, so I can't speak to whether his explanation makes sense.
I am a physicist. His explanation makes no sense.
EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way
Ow ow ow, I think they just broke my irony meter!
"I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
"It is a good rule not to put overmuch confidence in a theory until it has been confirmed by observation. I hope I shall not shock the experimental physicists too much if I add that it is also a good rule not to put overmuch confidence in the observational results that are put forward until they have been confirmed by theory."
- Sir Arthur Eddington
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If you want to do some armchair physics, these forums are really interesting. https://forum.nasaspaceflight....
People are attempting to recreate the "thrust-less" momentum at home basically. Lots of skepticism, lots of optimism, but real numbers being thrown around.
We're almost past the point of whether or not it works and moving onto why it works.
I'm interested in space exploration as well. There is a difference between an enthusiast and a space nutter. And no: Science Fiction is fiction. "Dream big" only works if you also "work hard" and are realistic about what is possible given the KNOWN LAWS of Physics. Just because you read Ringworld doesn't mean one can be built.
Space nutters are usually tech people who are uneducated in the hard sciences
Yet you don't seem to be able to discern who they are. You accused me of being a "space nutter" and I do have a background in hard science and engineering and accounting as well. I've built parts that have actually gone into space. I'm actually largely a voice of caution for those who spout overly optimistic timelines or economic absurdities regarding space travel.
You seem obsessed with that term "space nutter" like others are with hipster and you throw it at anyone who shows the least optimism about space travel. Lighten up. Someone who thinks that someday we might actually develop the technology to go to other planets or leave our solar system is just being optimistic. Nothing wrong with that even if they don't understand the technical details. It amounts to nothing more than fanciful musing. As long as they aren't hurting anyway with their day dreaming what do you care?
Yeah, space travel is an incredibly difficult problem and it will take a long time before we can do really useful things. This is not news.
First, "Sir Newton" is incorrect. If you're going to use "Sir", you have to go with "Isaac". "Newton" is correct, as is "Sir Isaac Newton".
Second, Einstein is more correct than Newton. Relativistic physics is pretty much the same as Newtonian for most practical purposes, but diverges under conditions Sir Isaac had no way to consider or test. We've tested relativity to death, and it's always at least as accurate, and in more extreme conditions much more accurate, than Newtonian physics. Meanwhile, we know that relativity is incomplete (we don't know how general relativity works on the quantum scale, for example), and presumably we'll eventually have even more accurate physics. It's conceivable that we'll get the laws of physics just right sometime, but it isn't happening right now.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
It's also possible that there are no new physics here, just an example of a misunderstood corner case of existing physics...
Build it, test it, see what happens. Until it's proven (and I mean really proven, not just dismissed) false, it would seem to be worth the research investment.
"Dream big" only works if you also "work hard" and are realistic about what is possible given the KNOWN LAWS of Physics.
Dreaming bit within the known laws stops progress dead in it's tracks. The laws of physics were derived from experimentation, observation and creation. People were getting shocks from electricity over 3000 years before Cavendish electrocuted himself for science and 40 years before current was properly described as a physical property. None of this gets explained by known laws.
While on the topic of electricity Benjamin Franklin published notes on the paradox that was the Leyden jar, something which was built but not explainable by physics. Here we are a few hundred years later and I'm communicating to you by typing on a keyboard sending 1s and 0s to you stored somewhere else on the planet only for text to come up on your screen.
You think too small. Known laws of physics get in the way of bigger thinking such as sending power wirelessly (thought impossible, along with everything else we take for granted now).
Why not? If this technology works, it changes the game in space travel. It seems there is a large requirement (today) for thrust vs energy, but with experimentation, theory, and improvements in understanding this may become viable for flying car type energy/thrust requirements. It really surprises me whenever I read a story about the EmDrive. It makes hypocrites of all the "scientists" and our general application of science, in general.
Skeptics claim:
"It violates Newton's law"
It is a bunch of tomfoolery
Its a measuring error
Horseshit. Any real scientist knows: Nullis in verba, or question everything. We thought the world was flat, we thought the world was at the center, then the sun, now... there is no center. We experiment, we learn, we work out what we think is right is right, or what we thought was right is wrong. The universe is mysterious, and full of wonder. Offer no ridicule until you have proven someone wrong, conclusively! Otherwise, your no better than a religious zealot. Science itself deserve better.
I think it's a prevailing attitude on Slashdot -- look at the comments of any article that has a positive outlook on future technology. But it's not just slashdot, it's true in most educated circles too -- general skepticism and cynicism. Most people's BS filters are turned to 100% -- which keeps them safe against the crazies, but saps the imagination. Even at work, doing natural language processing research, I find it a little depressing that the common view among my colleagues is essentially "human level intelligence will never happen".
You find it depressing because you can't handle reality. That is sad. No one has time to chase down every crackpot who comes up with a "magic machine". We have plenty of those. You cannot produce a machine that violates known laws and expect people to take it seriously.