New Test Suggests NASA's "Impossible" EM Drive Will Work In Space
125 replies, posted
[QUOTE] An EM drive working under a constant one milli-g acceleration would propel a ship to about 9.4% the speed of light, resulting in a total travel time of 92 years[/QUOTE]
Fun fact though - this is a bit wrong. It would take 92 years to [B]reach[/B] those 9.4 percent of the speed of light, and this is also exactly the time required to reach Alpha Centauri with said acceleration (i did some calculations just for fun). But it's pretty obvious that they would need to start deceleration somewhere at the midpoint between our sun and the destination star, so in fact they would reach this midpoint in around 64 years, resulting in maximum speed only around 6.5% of c.
[QUOTE=Oicani Gonzales;47639861]i still can't wrap my head around this
how can it be creating propulsion if there's nothing going in the opposite direction
i mean even ion thrusters work like that right[/QUOTE]
It probably can't. Whether it produces thrust or not, you can be pretty damn sure conservation of momentum is not being violated. More likely they don't know where the momentum is going.
[QUOTE=Cmx;47639907]So if this shit works in space, we would start seeing probes not needing any fuel to stay in orbit around planets, unlike the one that just smashed into mercury?[/QUOTE]
Pretty much. Also it generally promises quite incredible energy efficiency so we could get going REALLY DAMN FAST even with today feasible sources of energy.
[QUOTE=Ninja Gnome;47639813]if you're really lucky, 70 will be the new 40 by then, too[/QUOTE]
How is that luck? That means we'll have to work until we're 80-90 before we could retire!
[QUOTE=antianan;47639948]Fun fact though - this is a bit wrong. It would take 92 years to [B]reach[/B] those 9.4 percent of the speed of light, and this is also exactly the time required to reach Alpha Centauri with said acceleration (i did some calculations just for fun). But it's pretty obvious that they would need to start deceleration somewhere at the midpoint between our sun and the destination star, so in fact they would reach this midpoint in around 64 years, resulting in maximum speed only around 6.5% of c.[/QUOTE]
I'm pretty sure this is one of the most basic concepts of time when talking about relativistic speeds, but entertain me, isn't it true that people who would be traveling would gradually age slower and slower as it reached that % of the speed of light? Or is that just completely wrong and it'd feel exactly the same at 92 years.
[QUOTE=Eeshton;47640074]I'm pretty sure this is one of the most basic concepts of time when talking about relativistic speeds, but entertain me, isn't it true that people who would be traveling would gradually age slower and slower as it reached that % of the speed of light? Or is that just completely wrong and it'd feel exactly the same at 92 years.[/QUOTE]
You're correct. Someone on that rocket would age slower than someone back on earth in the same time period.
[QUOTE=Zero-Point;47640069]How is that luck? That means we'll have to work until we're 80-90 before we could retire![/QUOTE]
If 70 is your midlife point, I don't care if I retire at 100. It's not like whoever you're working for will expect much of you on that last homestretch of age 90-99.
[editline]1st May 2015[/editline]
[QUOTE=JohnnyMo1;47640085]You're correct. Someone on that rocket would age slower than someone back on earth in the same time period.[/QUOTE]
So, how might this work for return trips? 92 (earth) years would have passed when they return? And how long would it feel to the actual person on the rocket?
[QUOTE=MendozaMan;47639799]I'm still trying to get my mind around the whole "microwave radiation in an empty chamber creates reactionless propulsion" thing.
It just seems damn impossible, you cannot have an action that has no opposite reaction.[/QUOTE]
It probably is impossible. Conservation of momentum is derivable in just about every context in physics: classical mechanics, special relativity, quantum mechanics, quantum field theory... Theories which are all really accurate at all everyday length scales and down to the Planck length. The likelihood that they have discovered new everyday-scale physics by running energy through a funny-shaped device is minute. The only way we know of that this could work is exploiting large-scale effects of curved spacetime, but the device is far too small for that effect to be a likely explanation.
[QUOTE=Eeshton;47640074]I'm pretty sure this is one of the most basic concepts of time when talking about relativistic speeds, but entertain me, isn't it true that people who would be traveling would gradually age slower and slower as it reached that % of the speed of light? Or is that just completely wrong and it'd feel exactly the same at 92 years.[/QUOTE]
Afaik time dilation only becomes really noticeable at very high percentages of light speed
As much as a Star-Trek-optimist I am, I'm taking all of this with a grain of salt until a rigorous peer-review has been done and legitimate papers are written.
"Quantum fluctuations" is a hell of a buzzword that is automatically a red flag anywhere.
[QUOTE=Fish Muffin;47640173]Afaik time dilation only becomes really noticeable at very high percentages of light speed[/QUOTE]
I was taught it only affects life expectancy to a practical extent at somewhere around ~70-80%
Vsauce did a good video on relativity
[url]https://m.youtube.com/watch?v=ACUuFg9Y9dY[/url]
I would embed but I'm on my phone
y'know this is cool and all but if you can't figure out how it works then you really shouldn't tinker around with something that has the potential to fuck things up beyond our control.
[QUOTE=Eeshton;47640074]I'm pretty sure this is one of the most basic concepts of time when talking about relativistic speeds, but entertain me, isn't it true that people who would be traveling would gradually age slower and slower as it reached that % of the speed of light? Or is that just completely wrong and it'd feel exactly the same at 92 years.[/QUOTE]
Well, i've described how things would look like for people back on earth. But yeah, there is a thing called time dilation, so for crew members it would only take around 120 years (instead of ~130) to reach the destination.
Fuck sake im probably going to die on the verge of immortality and space exploration
Fucking typical.
[QUOTE=Superkilll307;47640250]Fuck sake im probably going to die on the verge of immortality and space exploration
Fucking typical.[/QUOTE]
I know. Wish I was born ~50 years from now. I want to be a space explorer! :(
Even if the device is somehow working true, there's no garentee that pumping in more power and making it bigger gets it to work better. Without an actual theoretical model of how it produces thrust its as good as useless to us.
Also I'm betting it does not scale up well at all even if its shown to work because at its heart its nothing more than a fancy magnetron
[QUOTE=Zombie_2371;47640275]I know. Wish I was born ~50 years from now. I want to be a space explorer! :([/QUOTE]
How instead of just "jumping in to the fun" we make the fun possible in the first place! Come on, facepunch. You can do better than that.
Just imagine being remembered in history for something.
[editline]1st May 2015[/editline]
Meh, what am i talking about.
[QUOTE=confinedUser;47640213]y'know this is cool and all but if you can't figure out how it works then you really shouldn't tinker around with something that has the potential to fuck things up beyond our control.[/QUOTE]
Fire and electricity have potential to fuck things up quite hard. So go ahead and stop using them then.
[QUOTE=Zombie_2371;47640275]I know. Wish I was born ~50 years from now. I want to be a space explorer! :([/QUOTE]
Too late for tall ships, too early for star ships.
[QUOTE=mijyuoon;47640568]Fire and electricity have potential to fuck things up quite hard. So go ahead and stop using them then.[/QUOTE]
Fire and electricity are a bit far from objects going (close to) relativistic speeds... I'm not really saying we shouldn't delve deeper but isn't it very possible that if an object was going a small % of the speed of light and it had some mass, it could just destroy the earth?
[editline]1st May 2015[/editline]
[QUOTE=Fish Muffin;47640580]Too late for tall ships, too early for star ships.[/QUOTE]
It's only too early if we make it too early. Are you expecting some revolutionary discovery to just happen because time passes? I think we all are to some extent, pretty sure Vsauce covered that type of thinking in one video.
[QUOTE=Eeshton;47640612]Fire and electricity are a bit far from objects going (close to) relativistic speeds... I'm not really saying we shouldn't delve deeper but isn't it very possible that if an object was going a small % of the speed of light and it had some mass, it could just destroy the earth?[/QUOTE]
Who is gonna point the goddamn thing at the Earth? And since it can't accelerate immediately you first must fly very far away and then turn around just to ram the planet. It's pointless (it's gonna take a lot of time as well). Also it's not like one man can do it, you need a crew that has technical/scientific knowledge.
Interesting, so this basically leaves us with three possibilities.
Possibility 1: There's some unknown mistake being made in the experimental process that is fucking up the results, even in different times and different labs.
Possibility 2: It utilizes some branch of science that humans don't have any knowledge of.
Possibility 3: It somehow takes advantage of forces we DO know about, but which according to our knowledge should only be usable by giant space gods.
[sp]Totally hoping for possibility 3, but reality is a cruel mistress[/sp]
Also this remind anyone else of the short Sci-Fi story known as the [URL="http://en.wikipedia.org/wiki/The_Road_Not_Taken_%28short_story%29"]Road Not Taken[/URL]? [sp]at least in reality if this is all real it won't be the Roxolani's fault we take over the galaxy.[/sp]
[QUOTE=jonu67;47640960]Interesting, so this basically leaves us with three possibilities.
Possibility 1: There's some unknown mistake being made in the experimental process that is fucking up the results, even in different times and different labs.
Possibility 2: It utilizes some branch of science that humans don't have any knowledge of.
Possibility 3: It somehow takes advantage of forces we DO know about, but which according to our knowledge should only be usable by giant space gods.
[sp]Totally hoping for possibility 3, but reality is a cruel mistress[/sp]
Also this remind anyone else of the short Sci-Fi story known as the [URL="http://en.wikipedia.org/wiki/The_Road_Not_Taken_%28short_story%29"]Road Not Taken[/URL]? [sp]at least in reality if this is all real it won't be the Roxolani's fault we take over the galaxy.[/sp][/QUOTE]
I just read that story! Its stupidly funny! Thanks!
Still waiting for more proof.
[QUOTE=confinedUser;47640213]y'know this is cool and all but if you can't figure out how it works then you really shouldn't tinker around with something that has the potential to fuck things up beyond our control.[/QUOTE]
How the fuck do you expect people to figure out how it works? With the above examples of fire and electricity, do you think we would ever have actually figured out how to use those to our benefit if we didn't tinker with them to figure out how they work? (Also a note there: We still don't 100% know how fire even works.)
[QUOTE=Alice3173;47641371](Also a note there: We still don't 100% know how fire even works.)[/QUOTE]
Yes we do.
[QUOTE=confinedUser;47640213]y'know this is cool and all but if you can't figure out how it works then you really shouldn't tinker around with something that has the potential to fuck things up beyond our control.[/QUOTE]yeah man screw this so called "sunlight", i don't understand it and it's scary, i'll rather stay here in the cave with my campfire
[QUOTE=cartman300;47641416]Yes we do.[/QUOTE]
I'm having trouble finding what I remember reading on Wikipedia about the subject (doesn't appear to be on the page for fire or combustion) but from what I recall we aren't actually certain of the exact mechanics behind things combusting. We now it requires fuel and air and temperature and such but we're not sure of the exact process it undergoes if I recall it correctly.
[QUOTE=confinedUser;47640213]y'know this is cool and all but if you can't figure out how it works then you really shouldn't tinker around with something that has the potential to fuck things up beyond our control.[/QUOTE]
Wasn't there a story about how when the atomic bomb was invented, it was theorized that it might start a chain reaction and ignite the entire atmosphere? Yet they tested it anyway.
Sorry, you need to Log In to post a reply to this thread.