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Star Trek's Warp Drive Not Impossible
Trunks writes "No doubt trying to ride the hype train that's currently going for the new Star Trek film, Space.com has a new article detailing how warp drive may not be impossible to acheive. From the article: '"The idea is that you take a chunk of space-time and move it," said Marc Millis, former head of NASA's Breakthrough Propulsion Physics Project. "The vehicle inside that bubble thinks that it's not moving at all. It's the space-time that's moving." One reason this idea seems credible is that scientists think it may already have happened. Some models suggest that space-time expanded at a rate faster than light speed during a period of rapid inflation shortly after the Big Bang. "If it could do it for the Big Bang, why not for our space drives?" Millis said.' Simple, right?"
You were faster than me, I was about to link the paper. IIRC it had something to do with instability for the energy requirements if you take into account not only relativist effects, but also quantum effects. I did not read TFA, but maybe it's just going along with the hype of the new Trek movie.
So to paraphrase Cubert... the engines don't move the ship, they move the universe around it?
Maybe we know now why Mark Millis is the former head of the project.
#DeleteChrome
er you do know you can't actually see faster than light travel as it is traveling faster than the light you re using to see it.
the best you can hope for is setting two atomic clocks that are synced exactly the same several light years apart and use that as your testing ground.
i thought once I was found, but it was only a dream.
Warp drives have the same drawback as wormholes. You need exotic matter to create the gravitational repulsion needed to distort spacetime in this unusual way. Other schemes for warp drives have been proposed, which allegedly overcame this obstacle, but they have their own drawbacks. ... [I]n fact, Ken Olum and others have proved that any type of warp drive [requires negative energy].
...
There are limits to the lifetime of any given amount of negative energy. For wormholes and warp drives these limits imply that such structures must either be very small, or else the region of negative energy must be extremely thin
Warp drives, if anything, are worse. To travel at 10 times lightspeed (a mere Star Trek Warp Factor 2) the thickness of the bubble's wall must be 10^-32 metres. If the starship is 200 yards (200m) long, the energy required to make the bubble has to be 10 billion times the mass of the known universe.
Engage.
The thing is ... quite often, there's a happy mid-way point between the completely ludicrous, and the "no can do" attitude. In your example ... how about mandating that all roofing tiles be white or reflective, and constructing all drivable surface from light-coloured concrete instead of black tar?
As much as it would simplify the process of meeting lonely, scantily clad, green alien women and make it possible for a geek to get a date, it seems that the only way to be sure that there is basis for this is to first create a time machine and go back to the big bang and verify the effect. The other problem then, is the fact that you won't get venture capital because of prior art. :
I agree with other posters that this might be far too coincidental to a movie release. It seems that radioactive spider stories declined after the release of Spiderman. I know correlation is not causation, but it might be suggestive
http://xkcd.com/552/
That's what the Romulans did.
There never were any widely accepted scientific laws that ruled out human flight, but most people, including scientists, still believed it was impossible. They lacked one of two things:
The OP's point is that we have to keep our minds open to new possibilities, because not all scientific laws are known yet, and the ones that are known aren't necessarily correct. We only call them 'laws' because they've lasted for a long time as 'theories' without being overthrown... yet.
Didn't we just have an article on this exact same thing a few days ago explaining why this is definitely NOT possible? (Emphasis added)
Nope. Not if you're referring to the hypothetical Finazzi instability and the possible problem of Hawking radition, anyway, that is anything but "definite".
It's not clear that the Hawking radiation issue applies to a Van Den Broek geometry warp bubble (vs Alucbierre's original warp sphere), nor is it certain (from Finazzi et al's paper) that the stress-energy tensor growth necessarily causes instability, or if it does that that instability can't be controlled. I mentioned some of this on my website about a month ago.
However, in the Star Trek context, it may be a problem that you can't create a Van Den Broek bubble big enough to enclose the Enterprise -- the bubble radius gets to about 50m before the wall thickness reduces to Planck length. (Of course given enough energy, anything is possible, but we're getting into energies with equivalent mass of the galaxy or better.)
-- Alastair
While I'm no expert on astronomy or the like, Space.com reported that the universe was 156 billion light years wide. For a universe that is less than 14 billion years old, this means that space itself has expanded more than 11 light years per year.
And that's where my understanding of things sort of fall apart, but I imagine that it's a bit like walking on a moving sidewalk. Relatively to space (the side walk) I'm only traveling at x, but space drags me along at a higher speed than that.
Two photons are emitted from a stationary point in opposite directions. What is the speed of photon A relative to photon B? I had assumed the answer would be 2*c, but if I understand you correctly you're telling me it's no more than c. This doesn't make sense to me...
I realize this may be an elementary question to some of you, but I'm not a physics nerd ;P
http://www.space.com/scienceastronomy/080923-dark-flows.html
In addition to the mysterious, and continuing observance of "Dark Flow", there is also the recently proven phenomenon of Frame Dragging, which was proven right here on earth. http://www.nature.com/nature/journal/v431/n7011/full/431918a.html
I dont think it unlikely that both frame dragging and dark flow are really the same thing; a distortion on spacetime caused by a static high energy aggregation. In the case of the earth and its impact on satelites, that energy source is the gravitational well of the earth, coupled with its axial rotation. In the case of dark flow, it could just be an emergent property of the local cluster having an unusual impact on the surrounding spacetime.
[begin wild supposition sequence]
Assuming that gravitational waves do in fact occur, it would mean that the periodic rotations of massive or energetic bodies (since mass and energy are equivilent under relativity-- a very low mass object with VERY high rotational energy could be equivilent to an object with heavy mass, and low rotational energy) could have a sympathetic harmonic reaction within the local spacetime-- Similar to how one can induce a standing wave in a pool of water with careful callibration of sonar transducers. http://www.mes.co.jp/Akiken/whatsnew/new20060724.html (page in japanese)
If similar properties can be measured and studied (in gravity waves), even small purturbations in a local spacetime could be greatly amplified by reinforcement from other sources, and produce "static" gravitational wells without the presence of a local causal mass. Viola-- Dark flow.
However, in order to create such a pocket of distorted spacetime one would first need to measure gravitational waves, then measure the effect of wave interference for the phenomena. Two things that have not been conclusively accomplished, and so, at this time it would not be possible to build the equivilent "wave tank" field generator for creating standing gravitational waves in the lab.
theoretically speaking, one could create "very" small gravitational waves using an array of off balance rotating masses, such as a lead weight on a motor shaft, as the source of the gravitational occilation. However, without a good measurement of rate of decay, or how these waves interact with one another, it is impossible to calculate what the "sweetspot" would be for creating standing gravitational waves, since you would not know how far apart to place the rotors, how heavy to make the masses, or what rate to turn them in relation to each other to produce the effect.)
If it could be accomplished, a wave amplitude far greater than could be generated by the standing masses, as a result of the accumulating energy in the reinforcement pattern introduced by moving the masses in such a precise manner. EG, the energy used for propulsion would be directly coupled to the energy used to rotate your small masses, accumulating in the local spacetime, and thus alter it's shape.
Rate of input would have to exceed rate of output for the accumulation to occur however, so we are talking a HUGE energy source requirement. Even an entire sun might not be enough to drive that kind of relativity curve, which is probably why we have only observed it in large star clusters. (Assuming this is indeed what causes dark flow)
Expansion doesn't have a speed. It's a scaling. Points will separate from one another at some speed, which is just the distance times the rate of scaling.
Consider ants on a rubber sheet. It's undefined to say that the rubber sheet is expanding faster than the speed of ants. You could say the ends of the sheet are separating at faster than the speed of ants.
On an infinite sheet, if the distance is great enough, you'll be able to find points separating faster than the speed of ants, even with a small scaling factor.
Maybe the real problem to solve is just how to make everyone immortal. That solves the issue of it taking tens or hundreds of millions of years to go somewhere. If I were a lifeform that had a lifetime of 10 minutes, going from New York to California would seem about as daunting as us going to the nearest star.
It really depends on how you consider "most". Large industrial farms operate differently than small farms. There are more small farms (say 100 acres or less) than big farms. The small farmer can't usually afford expensive fertilize, nor the equipment to distribute it. Think old family farms that have been operating for many generations.
Larger farms tend to be more product driven. It's worth the investment for equipment and supplies to keep every crop season as profitable as possible.
There are exceptions. Drive out of the city, and talk to a rural farmer. You'll likely hear how they have a particular crop that they grow once a season, just to till under to keep the soil rich.
I grew up on a primarily a cattle farm, with some separate plant crops. Once every year or so, we had to go out with "special equipment" to break up the cow patties. They were generally hard, and didn't break down all that well on their own. Our "special equipment" was an old box spring bed, with no wood or cloth on it. we hooked it to the back of a tractor, and systematically dragged it across the pastures. It was always a good excuse to drive the tractor fast around the pastures. :) After a couple rains, the grass grew much better, which in turn made the cattle happier. Well, happy until we took them for slaughter. Depending on the slaughter house, the cattle were killed on our property, or delivered alive. If they were killed on our property, a .38 point blank to the forehead did it quickly. It never took more than one shot. Cows are stupid. Even though we did this on a regular basis, they'd still just stand there and look at you while we did it.
It's strange how life changes. Now I haven't lived near a farm in about 20 years, and I've worked in major cities. I have no plans to go back to farming, unless some pretty substantial life changes dictate it.
Serious? Seriousness is well above my pay grade.
Turns out thats not enough energy. You need *more* energy that in the entire visible universe. Oh and negative matter (matter that that comes up as a negative for the mass energy tensor in the GR field equations), and thats *not* antimatter. Also you can't use a warp drive to collect all this energy either.
We have also left out that these solutions violate suspected conservation terms and that your warp bubble is causally disconnected from the universe. Seriously the infinite improbability drive is be better bet.
Ironically everyone is very optimistic science pretty much has this all wrong, and yet so confident in so many things with *far* less evidence and theory behind it.
The universe may indeed be stranger than we think. c may really be the ultimate speed limit.
Thats the bit that bugs me the most. We can do interstellar travel on paper without breaking any known rules or inventing a bunch of stuff we think probably does not exist. You don't need FTL.
ps yes I know you are being funny.....
The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!