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wrog(... Space postings start here but no prerequisites for this one...)
So I've been thinking some more about what our Galactic Empire is actually going to look like, assuming we ever get to that point. To be sure, I've been generally pessimistic about our ever getting out of this stupid solar system in any meaningful sense, the obstacles to practical interstellar travel really are quite insane, as I hope I've been able to convey.
But I've been peering at the math some more, and it's possible we're not completely screwed. There really are ways we can get Out There. In fact, I think I'm now getting a pretty good handle on how it's going to need to happen (i.e., if it's going to happen at all).
What I'm sure of is it's going to be different. It's not going to be Issac Asimov's Roman Empire in Space. Not Jerry Pournelle's or Elizabeth Moon's or dozens of other people's British Empires in Space. Polynesians exploring The Really, Really Big Pacific Ocean in Space doesn't really work, either, unless they were doing stuff with automated mechanical sea kayaks going off in all directions, finding islands and building stuff by themselves.
Suffice it to say, I don't think I've found the right metaphor yet.
Vernor Vinge's Qeng Ho cruising about the Slow Zone scenario definitely had a lot of thought go into it but, as of a few days ago, I'm now thinking he may be missing the boat, too.
Right now, I'm annoyed because I go out on the net to try to sanity check what I'm thinking and instead I'm seeing all of this horribly misinformed speculation about Shit That We Know Is Never Going To Happen, some of it apparently coming from actual physicists who really ought to know better. And perhaps they do and it's just that they're stuck writing for popular press, where, if you do too much crapping on the audience, dumping cold water, and killing their dreams, you stop getting asked back.
Luckily, since nobody's paying me to write anything, I don't currently have that problem. My only worry is that this is going to bore the shit out of you, because it's stuff you already know, or should.
But apparently, too many people don't. So…
At this point, the responsible author (people who are Not Me) would insert a whole pile of caveats re the possibility of some Fantastic New Discovery that Changes Everything, and, yes, it could happen. That guy who, in 1900, claimed powered, heavier-than-air flight was always going to be impossible, who, 20 years later, was undoubtedly feeling really fucking stupid, well,… nobody wants to be him; I get it.
But, as the science gets better and better understood, so do the boundaries. Special Relativity, the 2nd Law of Thermodynamics, Heisenberg's Uncertainty Principle, etc... none of that is going away as far as anyone can tell. Meaning it's becoming less and less likely that anyone's going to find a useful loophole to get us to any of the things you might have been led to believe are on the horizon.
Herewith, the list:
- Warp Drive: Not happening.
I've beaten this to death already, but, to recap, if we ever get technology that lets us pick any star in the galaxy we want, go there, and be home in time for dinner, that means we're in a Bill & Ted Universe until such time as somebody gets around to killing the inventor's grandfather.
And then it'll be Not Happening anymore.
(And yes, I know about the Alcubierre Drive. Not everything that people can code up in General Relativity is real; you can create any scenario you want and solve for what the mass distribution has to be, but nothing's going to tell you how to get there from the real world. In this case, feel free to wake me up when you figure out how to create exotic matter with negative mass — even antimatter has positive mass.)
Next!
- Stargate: Not happening. At least not in any useful sense.
- Yes, General Relativity allows solutions that twist space like a balloon animal.
- Yes, the Kerr-Newman and Reissner-Nordström metrics (for spinning and charged black holes, respectively) have weird artifacts that we're not sure how to interpret.
- Yes, that drawing Madaleine L'Engle did in "A Wrinkle in Time" with the ant walking from one end of the string to the other being saved by moving the ends of the string together was a wonderful analogy. Too bad there's nothing that it's actually an analogy for.
Granting for the sake of argument the possibility of Future Us being able to play Black Hole Bumper-Car Derby with sun+-sized masses -- note that we're going to have to get really far away from our own solar system (unless we don't care about it anymore) just to be able to do the experiments here -- to punch through to Somewhere Else, assuming that doesn't just get us a one-time-one-way trip, all indications are that the various Somewhere Elses will be otherwise be completely off the map -- other universe? billions of light years away in this universe? doesn't really matter -- and that's just Not What We Need.
Never mind that once you're out the other side of the gate, you're still stuck with the same problem to solve: How to get anywhere useful when everything you might care about is light-years away from the gate and you only have the stupid sublight drive. 27 working stargates would just mean we have 27 galaxies in which to be hosed instead of just the one. Yay. Are we done yet?
- Teleportation (Transporter, Holodeck, etc.): Goddammit. No.
You understand that the only reason this idea is even out there is Gene Roddenberry wanted to save 10 minutes out of every episode by not having to depict a shuttlecraft landing every week. Right?
Yes, it was a cool special effect for 1966, and that's all it ever was. It is not based on any known or even remotely plausible extrapolation of any known science. The Uncertainty Principle -- which makes it provably impossible to scan anything precisely enough to create an exact duplicate of it, let alone transmit it anywhere -- should have killed this whole idea completely dead before anyone ever got close to taking it seriously.
And, yes, there's this effect they call "quantum teleportation". The people who coined that terminology need to be shot in the head. It doesn't mean what you might think it does. This is what comes of raising a generation of physicists on Star Trek.
Yes, QT, if they can get it to work, will have some cool cryptography applications, I'll give it that. But it's never going to move macroscopic objects around. It's not even going to give us FTL communication.
- Consciousness Upload: Not Happening.
Or, rather, I regard this as a subcase of We Create Crazy Artificial Intelligences That Go Off and Do Stuff, i.e., what you thought was happening in this scenario is not what's actually happening, and there's no way to prove otherwise.
All I have to do is take the supposed magic device that scans your brain and somehow captures everything that matters -- recall that I already have an opinion on this, see previous item -- for upload into the computer that drives the spaceship that can then, presumably, head off into infinity free of the limitations of human lifespan and whatever else,…
and replace it with something that instead creates an AI that imitates you, passing every test anyone can think of, but is, in fact, Not You, in some important sense, and uploading that instead.
You die, the ship sails off into the sunset pretending to be you, and nobody's the wiser.
And even using the original device I would still contend that you die, the ship sails off into the sunset pretending to be you, and nobody's the wiser.
(… damn, I have a full Artificial Intelligence rant that needs to be written; one thing at a time …)
- The EM Drive: No. Just, no.
As a matter of general principle, if you have something that, if it actually worked the way you claim it does, could be made into a perpetual-motion machine, you are very, very, very, very, very, likely to be missing something.
Wake me when there are actual results in peer-reviewed paper. (N.B.: New Scientist and Popular Mechanics are not physics journals, last I checked.)
- Bussard Ramjet: Ummm.
Well, okay. This is the one thing on this list that is not like the others, because this was actually vaguely plausible when first proposed 60 years ago. Since then, assumptions about interstellar hydrogen density that this depends on seem to not be holding up.
My current take is that, in the (IMHO) unlikely event these actually work, there's an inherent speed limit (i.e., you won't get anywhere near lightspeed with them) -- more detail here -- and if other things on my wish list (we'll get to it) materialize, they won't be needed anyway.
They do get points for being cool.
- Long-Term Suspended Animation: Not Happening.
I should be a bit careful because there are actually two ways people propose doing this, and they're quite different- The physics way is where we create the magic field that actually stops time or slows it to a crawl somehow. There is exactly one way that uses real physics to do this that we know of: Park your subject near the event horizon of a black hole.
And if you think about it in GR terms, the sheer amount of stretching of spacetime you have to be doing in order to get a clock running 1000 times slower, you're going to need a black hole; a mere planet or star isn't going to do it. Which should give you an idea of just how absurd this is (i.e., putting a black hole on a ship so that we can do suspended animation? Um, right…).
- As for the biology way, we need to be careful to distinguish short term vs. long term SA. I have no doubt we're going to get better at putting people in comas or bringing them back from various kinds of momentary clinical death situations, or keeping somebody's heart stopped for longer periods of time while special kinds of surgery is happening. There's been excitement about this recently.
And that's not what we need. The issue is how to have a healthy 25-year-old embark on a 600 year trip to Tau Ceti and somehow wake up at the end of the journey as a healthy 25-year-old? That means you're stopping the aging process. We have no clue how to do that and there's no indication we'll ever be able to do that. Body parts wear out; cells die; cancer happens; bacteria eat stuff. Freezing works really well if you're an amoeba; not so much if you're a more complex organism: It slows down some processes, but it also does a whole lot of other damage that we have no idea how to repair.
Not happening.
- The physics way is where we create the magic field that actually stops time or slows it to a crawl somehow. There is exactly one way that uses real physics to do this that we know of: Park your subject near the event horizon of a black hole.
- Gravity Generators and Inertial Dampeners: Not Happening
If you want artificial gravity your two choices are the centrifuge/gerbil-wheel or keeping the engines on (constant acceleration). For anything else you're gonna need a portable black hole, which will probably be more dangerous than it's worth; same issue as for trying to do Suspended Animation this way.
And everything that applies to creating acceleration also applies to making existing acceleration go away, the only way to keep people from feeling acceleration being to arrange things so that they're not actually being accelerated. Either that or (you guessed it!) you need a black hole somewhere in there.
- Generation Ships: Not happening,
because the whole concept is fundamentally hosed and not going to solve anything.
Read Kim Stanley Robinson on this if you haven't already.
The biggest problem is there's so much about ecology that we have yet to learn. We humans are nowhere near as separable from our environment as we might originally have thought we were. Which means we really can't go anywhere long-term without bringing our environment with us. Which means that- learning to how to build an independent self-sustaining habitat,
- learning how to terraform a small planet, or
- learning how to manage our current planet (which, like it or not, we are currently in the process of terraforming)
Which then gets us to the question of what we should be looking for in exoplanets, another subject rife with misconceptions. (to be continued here)
no subject
Date: 2020-12-16 01:57 am (UTC)no subject
Date: 2020-12-16 03:09 am (UTC)Brin goes outside the envelope all the time (e.g., in the Uplift books, his aliens are doing all kinds of magic and he had Einstein being wrong in 100 different ways)
Also seems like the best writers tend to be really good at keeping one from noticing their story is full of holes.
no subject
Date: 2020-12-16 04:01 am (UTC)no subject
Date: 2020-12-16 10:55 am (UTC)