Species with language and toolmaking capabilities seemingly grow in technological sophistication at an exponential rate, so on the geological timescale, will quickly acquire space flight, grow to populations of trillions, harness the resources of their star system, then move onto settling a new star, and so on.

You're making the assumption that the problems involved with prolonged space travel are solvable with the time and resources we have here.

It could not be. It could be too expensive to colonize beyond the immediate area. If even the immediate area can be colonized.

There's also the assumption that there's going to be a good reason to make a non-returnable investment. Because, at some point, that's what it is. The speed of light is a limit we have not even come close to exceeding, much less approaching. And even if we do, and the people on the ship, time dilation, yadda, yadda. It does not matter. The people on Earth will still experience time normally. It taking the ship no time at all does not matter if it takes 1000 years on Earth. Or even 50 years. The return has to be phenomenal or the cost negligible.

You're right though. I haven't actually done a careful estimate of the resources required vs the resources available to a Type II civilization. If the former is significant relative to the latter, and there is no Return that can motivate that magnitude of an investment with the type of investment structures that will evolve on a solar-system-wide economy - where investment time horizons have no need to be extraordinarily long - then maybe interstellar colonization is not inevitable.

Why do you assume the cost of settling other stars would become negligible?

Our solar system is not a Dyson Sphere. What makes you think it will become one?

We don't have a population of thousands of trillions. Why do you think we'll get there in a manner in which all of them will be coordinated under one banner?

What makes you think that laser propulsion will be practical for such applications? Considering we haven't had a single laser propelled craft used in space exploration. Also, 0.2c is a clever way of not saying 20% the speed of light. Or 100 million miles per hour. How long do you think it will take to get a person to that speed? At 3g, it would take over a month of pure acceleration. The human body can withstand 3g for about an hour. You'd have to accelerate closer to 1g once you've broken Earth orbit. And now you're talking months. Months to accelerate, months to decelerate.

So yes, if we solve all of these other really, really, really, really hard problems, some of the other problems aren't that hard.

Because 1. of the accelerating rate of technological progress that we've seen over the last 2 million years, and 2. the deduction that preferential selection leads to economic systems that harness more energy and replicate themselves becoming more common

>>We don't have a population of thousands of trillions. Why do you think we'll get there in a manner in which all of them will be coordinated under one banner?

They wouldn't need to all be under one banner.

>>What makes you think that laser propulsion will be practical for such applications?

Because we understand the physics of it. It's theoretically possible, and assuming sufficient advances in science and engineering, will become practically possible.

>>And now you're talking months. Months to accelerate, months to decelerate.

I don't see such a requirement preventing interstellar colonization.

So, in other words, no clue, just wishing. You've seen a logarithmic rise and don't even consider that it could level off in the same fashion. The graph of technological advancement could be an arctan.

> They wouldn't need to all be under one banner.

So everyone handles their part of the sphere? And how do we decide where to go once we get it moving?

> Because we understand the physics of it. It's theoretically possible, and assuming sufficient advances in science and engineering, will become practically possible.

In theory, there is little difference between theory and practice, in practice there is a hell of a lot of difference.

Also, I'm not granting your assumptions. Why do you believe those assumptions? You've not given a reason besides that you believe that we will continue progressing at an exponential rate.

> I don't see such a requirement preventing interstellar colonization.

Then you don't understand the problems.

The logarithmic rise has been in place for a long time. The likelihood that it ends in the near future, before long-range space flight, seems unlikely.

This is especially so because the resources and capabilities being unlocked by new innovations seem to be inherently expand human civilization's rate of innovation.

For example, the cutting edge of technology today, like reusable rockets, NN-based machine-learning, and 3D printing, seem very likely to exponentially increase the resources/productive-output of our civilization.

Intuitively, I don't see any reason this accelerating progress will stop until physical laws become the only major limiting factor, and these laws allow for an exponentially expanding, seafaring civilization.

Of course, I don't know for certain. It goes without saying that these sorts of discussions are speculative.

>>So everyone handles their part of the sphere? And how do we decide where to go once we get it moving?

We don't need to propel the entire Dyson Sphere. Some group(s) needs to create a massive laser emitter, and use it to propel an artificial craft.

>>In theory, there is little difference between theory and practice, in practice there is a hell of a lot of difference.

Theory tells us what is possible. History tells us what to expect in terms of long term trends.

Based on the longstanding trend and intuitions about the nature of technological/economic evolution, I think we can expect anything that is theoretically possible to do with a small fraction of the resources extractable by a Type II civilization, will be done by human civilization, and hence interstellar colonization will be possible.

That's just one failure scenario, if you took a Wifi signal and could somehow transport it back in time 100 years and blast it out at 1000 times the normal energy how long would it take past us to notice?

Also, for mild amusement, your comment reminded me of this video https://www.youtube.com/watch?v=b9UO9tn4MpI