Discussion in 'Biology & Genetics' started by Dinosaur, May 17, 2017.
Exactly. And siteless teleporters are teleporters.
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Very little in science is taken as such.
Science is always open to correction.
I've read somewhere (apologies, no link) that even theoretical wormholes would only be tiny, as it requires a certain amount of negative energy consolidated in one place, and this seems to have a limit.
But if this limit was removed, some have calculated that a wormhole the size of a grapefruit would take energy equivalent to our sun's output for 100 million years.
The issue with FTL, as far as I see it, is not that something can't go FTL but that it can't accelerate past the asymptotic barrier of lightspeed itself.
The closer you get, the more energy is required, the heavier you get relatively etc.
At light speed you are of infinite mass, require infinite energy etc.
Or so the equations suggest.
However, what if there was a way to skip over that barrier and not actually travel through it at all?
In the same way that electrons have energy levels, and if they jump levels then there is no motion through the intervening levels but a straight jump from one to the other.
"Warp" per Star Trek is not actually FTL in the true sense, but more akin to stretching and contracting spacetime itself in front and behind the vessel.
In the same way that distant galaxies are not moving FTL away from each other but rather the apparent motion is FTL due to the expansion of spacetime.
But yes, for sci-fi, travelling FTL is pretty much a given in some manner or other if the story is to take place between star-systems.
But some is all the better for it for sticking to the current understanding of physics.
"The Expanse", for example, was relatively hard sci-fi in that the orbital mechanics were pretty much as you'd expect, with the exception of a seemingly rather powerful and low-fuel engine.
Exponentially so, if I was writing it.
One thing I find sloppy in some sci-fi is the lack of extrapolation of a given tech and thus ways that the tech is limited.
E.g. Some may use anti-matter as a fuel but then not address the issue of the craft effectingly being a bomb.
So how is anti-matter restricted?
And then stories where high velocities are allowed, you basically turn craft into kinetic weapons.
A 1,000 kg ship travelling at light-speed has on the order of 10^19 joules of kinetic energy.
This is equivalent to c.20,000 megatons of TNT.
The total global arsenal of nukes is c.1,500 megatons.
So how does the story stop ships travelling that speed from destroying planets?
So in the quantum drive, how do you stop the drive from transporting huge chunks of a planet into space?
Could you create weapons using the tech that basically create a swarm of miniature engines that latch on to an enemy ship and then teleport themselves and the adjoining hull to somewhere else?
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No. It's not a barrier; it's an aysmptotic limit.
Here is one way of looking at limits:
Imagine an airplane that can only fly due north and due south. It can go extremely fast when it needs to.
It flies from Washington DC to Ottawa - 400 nautical miles.
But it must do so in a 40 knot Westerly wind, which blows it off course to the East.
Doing 200 knots, the plane is blown off course to the East by 80 nautical miles over its one-way journey.
Doing 400 knots, the plane is only blown off course to the East by 40 nautical miles.
Doing 4000 knots,, the plane is only blown off course to the East by 4 nautical miles.
If it could do 40,000 knots,, it would only blown off course to the East by .4 nautical miles.
How fast must the plane go to not be blown off course at all?
Obviously, infinite. There is no speed the plane can do that will not have it blown off course to the East.
If you were to graph plane speed versus error, you would see a line that approaches - but never reaches - zero. No matter how high plane speed, error in flight path never reaches zero.
Now ask yourself: how fast must the plane fly to find itself to the West of its destination?
The question doesn't even make sense.
In the same way, c is not a barrier; it is the asymptotic limit. There is no beyond.
In this case, what happens is, time contraction approaches infinity. The closer you get to c, the slower your time relative to the rest of the universe. If you were to project that to c, you would have to describe a state where you are stopped - frozen in time, by the reckoning of the rest of the universe. It doesn't even makes sense to ask what would happen if you could go even faster. There's nothing slower than stopped.
Please don't get hung up on the use of barrier v limit.
If you had read what I wrote it is clear that I am using the term barrier as you would use the term limit.
Note the "infinite mass" and "infinite energy" etc.
If you feel you could provide that much, or more, energy then feel free to consider the terms, as used, to be different.
But thanks for your explanation. Please Register or Log in to view the hidden image!
Also bear in mind that the comments (i.e. possible means of FTL) are with regard sci-fi, and not strict scientific understanding where I believe it is accepted by all that FTL is not possible.
Or that's the myth anyway. I don't entirely believe it.
The remark you are replying to is taken from me talking to Sarkus. Sarkus had expressed his (seemingly reasonable) opinion that worm-hole transportation is more plausible than FTL transportation, because wormholes correspond to solutions of some equations in theoretical physics.
I wouldn't know, myself. I'm most emphatically not a physicist. (This is the biology forum, believe it or not. That's where my small scientific background lies.)
But forging ahead anyway, when it comes to theoretical physics and its equations, I'm always a bit skeptical. Their beloved heiroglyphs are human-constructed conceptual models, typically models of physical realities that are far more complicated than the formally-simple models that seek to capture the physical realities' essential structure. So in my own mind at least, I don't accord the mathematics any absolute certainty. Theoretical physicists talk about 'proving' this or that, but all they are saying is that some conclusion follows logically from their mathematical heiroglyphs. (Garbage in- garbage out. It all depends on the truth of the assumptions.)
I'm not sure what 'negative energy' means. I guess that quantum uncertainty stuff might allow micro-wormholes down there on the Planck scale. Or something, I don't know. That's all speculation.
It seems to me that somehow warping the universe to make here and 20 lightyears away physically coincide, would be a hugely violent thing. It would (so my science-fiction intuition tells me) create all kinds of distortions in the space and presumably the resulting physics surrounding the wormhole.
It wouldn't be a nice benign little Stargate that you could hide in a mineshaft in Colorado where you could just dial up a destination when you want to and then step through. If Einstein attributed gravity to geometrical warping of space, I suspect that the tunnel entrance to a worm-hole would resemble a black-hole. A very nasty thing to be standing anywhere near. Trying to travel through one might mush you into subatomic particles.
Or so Einstein's heiroglyphs seem to imply.
Sure, but what if the equations aren't exactly right? I tried suggesting to Sarkus that Einstein's general relativity equations are basically the result of Einstein assuming that the speed of light is constant in all (non-accelerated) frames, no matter how fast they are moving relative to one another. So Einstein had to monkey around with other spatial-temporal variables and metrics, so as to allow everything to remain consistent. That's where all that asymptotic stuff comes from as C is approached.
But once again, it's only as good as the assumptions that went in.
We already know that the speed of light varies in different media. The speed of light is slower in water, even slower in glass, and only something like 70,000 miles per second in diamond. So lets assume (simply for the sake of science-fiction) that 'vacuum' isn't the same thing as 'nothing'. (We've been arguing about that in another thread.) Let's hypothesize that all that quantum field theory stuff is something and that it has some effect on retarding the speed of light, just as water and glass do.
So imagine some damping field that smooths out all the unruly quantum field stuff (without thereby evaporating the spaceship that's generating the field, I don't know how that would work, maybe the damping field could be contained in its generator and projected ahead of the ship) converting the kind of quantum field theory 'false-vacuum' that we observe in space into a more voidy kind of vacuum (hypothetically with a higher speed of light).
Purely for the sake of science-fiction remember. It's all speculative fiction.
That kind of scenario might call for some future modification of Einstein's mechanics, just as things like the Michelson-Morley experiment and the failure to detect ether drift led to Einstein's modifications of Newton's mechanics. Those modifications might get rid of the asymptotes, at least for super-luminal velocities in interstellar space.
I wasn't just being pedantic over terminology.
You went on to say that a barrier is something you could jump over, as if there is another side. So no, we're not using the terms interchangeably.
I think it's a mistake to think of it that way, or encourage others to think of it that way.
Yes, even in science fiction.
Yet in the end our understanding does improve.
When observations can not fit within the current theory, find a new theory.
It's the energy that helps keep the universe at net-zero balance. Please Register or Log in to view the hidden image!
E.g. gravitational energy.
Highly speculative, even.
People once thought that travelling at what are now relatively slow speeds would be fatal.
So who knows. Please Register or Log in to view the hidden image!
Seems to be confirmed with every experiment, though.
So for now we should probably accept it until such time as it doesn't account for things we observe.
This could be much the same as supercavitating torpedos.
They create a bubble of air around the torpedo, with the torpedo able to travel much faster as a result - far faster than a normal torpedo.
I might use that (if I ever pen a novel or two)! Please Register or Log in to view the hidden image!
Sure, the model / equations may well have a limit of applicability but that does not make them any less correct in the realm at which they are applicable.
I assure you we are using the terms interchangeably.
But our views of what constitutes valid science fiction clearly differ. Please Register or Log in to view the hidden image!
Hi Dinosaur. Please Register or Log in to view the hidden image!
Computers communicate at the speed of light so perhaps some computer based technology could allow star-gate travel. Maybe downloading oneself into a computer...
Until or unless someone can explain why the end points of wormholes should remain stationary or move relative to the surfaces of planets, or track the position of moving Gou'auld spacecraft, this (a 'Stargate') remains another one of those "absolute Euclidean-relativistic aerher wind geometrical space" fantasies.
For that matter, what do clocks do on the interior of a wormhole and why is it different than time dilation just outside of the extreme ends? Don't bother answering. It's like asking what happens if a unicorn mates with a rhinoceros at relativistic speed? Maybe you get some kind of narwhal-turtle thing. Makes the same amount of sense, for the same reason. There is very little reason, and no science involved at all. An 'event horizon' doesn't work the way it does on Stargate, and it isn't associated with quantum entanglement, either.
It's also annoying when science actually stops advancing because the stories that derive of a myth are more popular ideas than scientific facts. In that respect, Star Trek was mostly harmless. What does it really matter if the Enterprise can't exceed the speed of light? Time dilation will take care of everything else rthat would need to happen, other than shields and shuttlecraft, that is. Don't even bother responding to that either. It goes nowhere but Stan Lee's Marvel universe. And Donald Trump's fantasy presidency where global warming never goes is a stop at the same train station's comic book outlet.
Wormholes were originally proposed by Einstein, Podansky, and Rosen, to explain quantum entanglement. Like time travel that results by exceeding the speed of light because some mathematician was gullible enough to believe that deciding by zero wasn't so much an error and abuse of proportional math as it was being closer to the mind of G-d by means of contemplating infinity, it makes for better fiction than it does a description of this reality.
If I remember the tchnobabble well enough, the wormholes in Stargate were artificial, and were formed by dialling the address of the destination gate.
However, due to the relative motion of planets, ships and so on, the gate automatically adjusted the address for you so as to offset that motion.
Simples, really. Please Register or Log in to view the hidden image!
I have only just now noticed this thread - any objection to moving this to Sci-Fi and Fantasy (and fixing the thread title because... rage... yeah... lol)
Yeah. I thought the placement was strange also.
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