I'm playing with imaginary physics again
Feb. 11th, 2011 04:26 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
beccaelizabethSay you've got a stable wormhole with a gate on either side, your basic stargate. Both sides of the wormhole are having the same day. You talk back and forth, it's like there's a funny looking gate between you, no problem.
Weird relativity paradoxes happen when you start making one end of the gate travel really fast.
Say you're using stargates to go travel to the stars. One end stays at Sol, the other travels really fast to the next star along.
It has to be spectacularly fast to get spectacular time distorts, but we'll ignore how hard it is to get up to speed, because all you have to do is make one end of the stargate be that fast once and then it will spit out fast ships for you forever.
So, okay, one end of your new stargate is at Sol, the other end is travelling very fast, and there's a big time distortion effect going on. It travels 7 light years to a new star, it feels like 7 days. This would mean 7 days pass for the wormhole, which means 7 days pass on Earth before you can step through the gate and be in a new star system. You are now 7 years in the future. But you could ignore that, as long as all the contact you had with anything was through this gate. Both sides of the gate would just keep pretending it was the same day, because that was the experience you'd have.
Right?
Probably right.
So, you keep sending out these gates. You start from the new star system, drop one end of a new wormhole there, send the other end out at near light speed, spend another 7 year week getting to a different star. Keep on going, make a ladder of gates, by dropping one end and moving the other. It takes days or weeks as far as anyone can tell, experience says it takes days, as long as you keep on going straight.
But if you have 3 gates, Sol, Alpha, Beta, and the one in the middle breaks, you have to send out a new gate.
It breaks on the same day in Sol, Alpha and Beta. You can still get from Sol to Alpha, so it keeps on being the same day on Sol and Alpha. They start a ship at Alpha to take a new gate to Beta. Sol and Alpha think it takes a week. Beta thinks it takes 7 years.
... I think.
So if anywhere gets cut off, it gets cut off for a long time, and suddenly they have to pay attention to this time travel aspect of the gates.
They also have to pay attention if anybody loops back in normal space at sublight speeds. You get weird time travel with loops. But I think with straight lines they could pretend it wasn't time travel until something broke.
If they went out in straight lines from Sol and then built crosslinks then weird time travel would happen again. You could jump around to plot your route so you arrive before you leave. Brain breaky.
(I keep on conceptualising this gate network as kind of like the London Underground, where you have stations that get you to other stations quickly, but if you get out and walk around it takes longer. So now I'm imagining a tube journey that can, by changing train lines a lot, arrive before it leaves. *blinks*)
The wormhole nexus in the Vorkosigan books doesn't necessarily connect all the places in the same year. Wormholes are weird like that.
... also, 'same year' gets to be a vastly tricksy concept once you start trying to figure this physics stuff out. No wonder the Doctor loses track of his age.
Of course actual real physics says wormholes can't do sitting around being stable so spaceships can go through them, but that's no fun at all.
Weird relativity paradoxes happen when you start making one end of the gate travel really fast.
Say you're using stargates to go travel to the stars. One end stays at Sol, the other travels really fast to the next star along.
It has to be spectacularly fast to get spectacular time distorts, but we'll ignore how hard it is to get up to speed, because all you have to do is make one end of the stargate be that fast once and then it will spit out fast ships for you forever.
So, okay, one end of your new stargate is at Sol, the other end is travelling very fast, and there's a big time distortion effect going on. It travels 7 light years to a new star, it feels like 7 days. This would mean 7 days pass for the wormhole, which means 7 days pass on Earth before you can step through the gate and be in a new star system. You are now 7 years in the future. But you could ignore that, as long as all the contact you had with anything was through this gate. Both sides of the gate would just keep pretending it was the same day, because that was the experience you'd have.
Right?
Probably right.
So, you keep sending out these gates. You start from the new star system, drop one end of a new wormhole there, send the other end out at near light speed, spend another 7 year week getting to a different star. Keep on going, make a ladder of gates, by dropping one end and moving the other. It takes days or weeks as far as anyone can tell, experience says it takes days, as long as you keep on going straight.
But if you have 3 gates, Sol, Alpha, Beta, and the one in the middle breaks, you have to send out a new gate.
It breaks on the same day in Sol, Alpha and Beta. You can still get from Sol to Alpha, so it keeps on being the same day on Sol and Alpha. They start a ship at Alpha to take a new gate to Beta. Sol and Alpha think it takes a week. Beta thinks it takes 7 years.
... I think.
So if anywhere gets cut off, it gets cut off for a long time, and suddenly they have to pay attention to this time travel aspect of the gates.
They also have to pay attention if anybody loops back in normal space at sublight speeds. You get weird time travel with loops. But I think with straight lines they could pretend it wasn't time travel until something broke.
If they went out in straight lines from Sol and then built crosslinks then weird time travel would happen again. You could jump around to plot your route so you arrive before you leave. Brain breaky.
(I keep on conceptualising this gate network as kind of like the London Underground, where you have stations that get you to other stations quickly, but if you get out and walk around it takes longer. So now I'm imagining a tube journey that can, by changing train lines a lot, arrive before it leaves. *blinks*)
The wormhole nexus in the Vorkosigan books doesn't necessarily connect all the places in the same year. Wormholes are weird like that.
... also, 'same year' gets to be a vastly tricksy concept once you start trying to figure this physics stuff out. No wonder the Doctor loses track of his age.
Of course actual real physics says wormholes can't do sitting around being stable so spaceships can go through them, but that's no fun at all.