Expressions of Discontent

By far the commonest kind of science fiction, in books and on TV, is space opera, which is based around the idea that interstellar travel is common. Usually there are "galactic empires" and so on.

Well, forgive me for being pedantic, but the whole idea is so damned hokey, I just can't bear it. So, please, sci-fi programme-makers, I'm begging you now to stop this nonsense.

And don't tell me it's even remotely plausible. The nearest planets to Earth are multiple light years away, and since faster-than-light travel is impossible, any trip between planets on different solar systems would take years, if not decades. Neither trade nor government can go on across such distances.

Assuming (optimistically) that you can accelerate to near lightspeed and slow down again quickly without destroying the occupants, a round trip to the nearest planet would still take years, from the standpoint of those at either end. There's nothing worth trading over such distances. Nor is it possible to govern a place remotely at such distances, or even to maintain a friendly correspondence. Therefore, any colony would have to be entirely self-sufficient and self-governing. There's no advantage to the people of Earth in going to the expense of setting up such a colony, except in the event of a threat to the very survival of Earth as a habitable planet.


Here are some reasons why a galactic empire based on trade isn't an option:

• Suppose two planets are five light years apart, and a space ship takes ten years to cross that distance. You can't trade for cash, because you can't rely on the value of the currency you use not collapsing in the time it takes to cross the distance between the two planets. Actually, a currency collapse is pretty much a dead cert, since there's nothing at all to sustain the value of the currency. Trade will have to be by barter. (Not that that eliminates the risk -- it only reduces it.)
• There's little point in placing orders in advance, as that merely adds multiple years to your delivery times. Therefore, trade will almost certainly have to be speculative.
• You can't enforce contracts: if you send a spaceship bearing goods to another planet, and the people at the destination decide they don't want to pay for your goods, it'll take you years to find out, and when you do, what can you do? Send another spaceship after them?
• And what happens if you get a shipment of gizmos that doesn't fit your sockets? Do you send it back?
• You can't trust the ship's crew. If they jump ship at the destination, tough on anyone who owns shares in that ship or its cargo back home.
• There's no point trading in high-tech products, because by the time your product reaches its destination, your product will be out of date -- unless the people at the destination are so far behind you technically, that they have nothing to offer in exchange.
• Aesthetic goods run a very high risk that when they arrive, they will not accord with fashion.
• If you're very lucky, you could find yourself living on a hospitable planet that happens to be, or to be close to, a rich source of a highly valuable material (uranium, perhaps) that you can sell. But you also have to find another planet that not only lacks the thing you want to sell, but has something you need, that is worth the cost of delivering your surplus to them. That requires quite incredible luck.

So, galactic, never mind intergalactic, trading empires are impossible. Of course, impossibility is not a reason why something can't be allowed to happen in fiction, but the central conceit of sci-fi is that it is scientifically plausible. Let's have some more original ideas in sci-fi.