Alien Life, Interstellar Travel, and Million year Civilizations

[Reynard]

At one time, there was no "realistic" way to go around the Earth in 24 hours.

Nobody is saying "launch today". We recognize that there's work to be done. But that work won't be done if everyone says, "There is no realistic way to do it now, so we shouldn't do anything."

To be clear, I am not saying that at all. What I am suggesting is that given how hard it would be, there would be far better uses for that level of scientific and engineering power and the resources necessary. You could put a self sustaining outpost on every moon in the solar system for what it would take to make a single ship that could carry 50,000 people across hundreds of light years over thousands of years.

 

[Umbran]

Again you are assuming the nanite is doing the energy focus. I was saying they could construct molecular scale channels to do the work. The nanites construct the channels, not that the nanites themselves are doing the channeling.

1) Abstract "channels" are not a thing. Energy does not move in the abstract, but in real, physical forms.

2) Isaac Newton. Remember him? For every action, there is an equal and opposite reaction?

Whether it is done by a nanite, or a "channel" - somewhere down there you have something trying to mash hydrogen atoms together. But, down there, those nucleii are both positively charged, and will repel each other. You must apply force such that you overcome that repulsion.

Whatever applies that force will, by Newton, also feel the same magnitude force applied to it. If that thing is only molecule sized, it will break, because the repulsive force between the two nucleii will become much greater than the strength of molecular bonds before the fusion can ocurr.

This is why everything we use to contain nuclear reactions is much, much more massive than the amount of matter that is reacting.

 

[myrkulyte]

There are solutions to the unbalance, both extremely technological and relatively simple. The easiest would be a fluid in a ring around the torus, with a series of baffles to limit motion. As weight is redistributed the fluid naturally moves to stabilize the system.

Recall that the fluid would not be under the force of gravity. Not sure that wouldn't still help though, interesting problem that.

Regardless, keeping a huge rotating ring in check would be a massive engineering problem no matter what you use to counter balance it. And it needs to fit in with all the other mission requirements.

 

[UngainlyTitan]

How do you propose to power that acceleration as it becomes ever more energy inefficient?

I think my initial reaction was how he proposed to stop. Travelling into or through a star system at that kind of velocity would impolite at best and it would be very bad if you bumped into something.

 

[Stalker0]

How do you propose to power that acceleration as it becomes ever more energy inefficient?

Oh its a staggering amount, even with fusion as an option you are likely talking like 50,000 tons of fuel if your sending a "real spaceship" out there.

Now is that a captain insano level of fuel?....it is. Is it beyond the realm of possibility....its not.


Again we can't look at today's technology and say how would you do this. The answer is...you don't. But we can make some realistic assumptions about future tech that could do the job.

1) Delivering fusion power at reasonable energy.
2) Industrial food creation. Aka producing food from energy + base materials rather than agriculture. The notion of growing your own food in space is a dated concept, we will make food an industrial process, and therefore much more space/energy efficient.
3) Next gen materials. We are already going through a material revolution right now both with AI assistance and simply that:
a) We have learned the fundamentals of how atomic structrure = material properties. We are no longer fumbling in the dark, we basically have an instruction manual.
b) Insane material "printing" capabilities. We have the ability to print materials at the atomic scale, creating a level of precision underheard of before.

So with that in mind, when people are discussing "how can we possibly have ships that aren't cooked by radition or could withstand dust moving at near relativistic speeds.....give it 20-40 more years. We are going to have materials that make our strongest stuff today look like toilet paper.

 

[Reynard]

Oh its a staggering amount, even with fusion as an option you are likely talking like 50,000 tons of fuel if your sending a "real spaceship" out there.

Now is that a captain insano level of fuel?....it is. Is it beyond the realm of possibility....its not.


Again we can't look at today's technology and say how would you do this. The answer is...you don't. But we can make some realistic assumptions about future tech that could do the job.

1) Delivering fusion power at reasonable energy.
2) Industrial food creation. Aka producing food from energy + base materials rather than agriculture. The notion of growing your own food in space is a dated concept, we will make food an industrial process, and therefore much more space/energy efficient.
3) Next gen materials. We are already going through a material revolution right now both with AI assistance and simply that:
a) We have learned the fundamentals of how atomic structrure = material properties. We are no longer fumbling in the dark, we basically have an instruction manual.
b) Insane material "printing" capabilities. We have the ability to print materials at the atomic scale, creating a level of precision underheard of before.

So with that in mind, when people are discussing "how can we possibly have ships that aren't cooked by radition or could withstand dust moving at near relativistic speeds.....give it 20-40 more years. We are going to have materials that make our strongest stuff today look like toilet paper.

There is not much to discuss if the idea is that "we will find a solution." Okay, fine. Now what? What does a interstellar human civilization actually look like? Is in A civilization at all, or a bunch of human civilizations? Are they even human? After all, terraforming is probably a lot harder than tweaking our genetic code.

 

[MarkB]

There are solutions to the unbalance, both extremely technological and relatively simple. The easiest would be a fluid in a ring around the torus, with a series of baffles to limit motion. As weight is redistributed the fluid naturally moves to stabilize the system.

One option I'm picturing is having a set of heavy weights on tracks circling the cylinder at intervals. When you detect precession you send a weight down the track to generate an opposite precession to correct it. The whole thing could probably be automated.

 

[UngainlyTitan]

There is not much to discuss if the idea is that "we will find a solution." Okay, fine. Now what? What does a interstellar human civilization actually look like? Is in A civilization at all, or a bunch of human civilizations? Are they even human? After all, terraforming is probably a lot harder than tweaking our genetic code.

I am not sure that terraforming is all that hard if one has time. If a civilization can survive over 10s of millions of years then I suspect that terraforming could be accomplished in the order of a few million years.
We have no real idea how that might work, we have never done anything like that. I that any species that can operate over deep time has learned a few tricks that we have not yet.
I was listening to a couple of economists today, discussing the fallout from the blockade of the Straits of Hormuz, that if our agriculture had to operate without fertilizer, we could only globally support a population of around 2 billion.
I bring this up to show that our current systems are quite fragile and there is a lot of work going into keeping the show on the roads at any given time.
I would expect that a society that is capable of operating on the timescales of centuries would be less fragile. Some built in cultural practises that mitigate both what the environment throws at it but also the failure modes of their own psychology.

 

[Mustrum_Ridcully]

Edited to include that, but not in time to beat you. That's one trip, then everything else is instantaneous.

No, that's not how quantum entanglement works. You cannot transfer information.

The relationship between your half and the other half is that if your half is +, the other half is -, or vice versa (+ and - standing for two opposing states you entangled, like spin, charge or whatever fancy things quantum mechanics have to offer here). But you cannot control which one of the pair is + or -. So if you measure a + on your particle, you know the other particle of the pair got a - and vice versa.
But what do you do with that? The only thing you can do now is send the other guys "hey, you're going to get a - if you measure it and no one measured it before you. So they don't need to check, or they can check and confirm. And after you measured it, the entanglement is gone, whether your particle is now a + or - doesn't affect the other anymore. It is useful for some things - like figuring out if someone tampered with your signal (though you still need to do some statistics - a lone particle still might have a 50 % chance to come up the same, after all, so you need more than one, but I suppose if you can send one entangled particle over several light year, sending a few hundreds or millions isn't going to be so hard anymore.). But you still need to send a signal the slow way to make this comparison.

 

[Reynard]

I am not sure that terraforming is all that hard if one has time. If a civilization can survive over 10s of millions of years then I suspect that terraforming could be accomplished in the order of a few million years.
We have no real idea how that might work, we have never done anything like that. I that any species that can operate over deep time has learned a few tricks that we have not yet.
I was listening to a couple of economists today, discussing the fallout from the blockade of the Straits of Hormuz, that if our agriculture had to operate without fertilizer, we could only globally support a population of around 2 billion.
I bring this up to show that our current systems are quite fragile and there is a lot of work going into keeping the show on the roads at any given time.
I would expect that a society that is capable of operating on the timescales of centuries would be less fragile. Some built in cultural practises that mitigate both what the environment throws at it but also the failure modes of their own psychology.

The assumption that there could be such a thing as a civilization that lasts for 10s of million of years is itself quite a leap. What makes people think such a thing could exist. Most species don't last 10s of millions of years.

And we already have a society operating on timescales of centuries. America has operated on that timescale, and it is young by global standards.