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Old 17th July 2017, 05:32 AM   #41
Darat
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Originally Posted by Fudbucker View Post
Even given distance, even given light speed limitations, a civ that can travel 10%C will have colonized the galaxy in a ridiculously short amount of time (in galactic terms). Earth would make a good colony planet, but there's no colony. So advanced civs don't colonize? Value indigineous life too much? Have already seeded the planet?
But you have to factor in costs of such spacecraft, it would be a resource draining exercise for even a single worldwide organised society.

Never mind that it would never be cost effective to ship people out to anything like even a single percentage point of the population so population pressure wouldn't push in the direction of colony planets.

I suspect it is simply the distances and resources required and sadly the limitations of technology in our reality.
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Old 17th July 2017, 07:16 AM   #42
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Our intelligence has given us the technological means to wipe ourselves out of existence but not the wisdom to avoid developing that technology. Perhaps other civilizations have fallen into the same intelligence gap.
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Old 17th July 2017, 07:23 AM   #43
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Originally Posted by McHrozni View Post
Early humans didn't colonize the globe out of any particular benefit for themselves, their society or to establish trade links or anything of the sort. It's a natural thing for humans to do, pure and simple.
Natural, sure. But how early are you talking? I bet the early humans explored purely out of a need to eat. They went looking for game, for arable land, for good grazing. As they prospered and their numbers grew, they went looking for space to live in.

"I wonder what's on the other side of that mountain range? Let's go find out, but if it's not a herd of buffalo and a clear-running stream, we're probably boned."
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Old 17th July 2017, 07:29 AM   #44
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I think there's another plausible explanation for the absence of the aliens (whether personified by self-reproducing machines or star-hopping serial colonists) from the local neighborhood. It's not because interstellar travel is impossible, but because achieving it requires adaptability and intelligence.

The idea that a mindless or single-minded machine can manage the task of reproducing itself in a new and unfamiliar environment is pretty much taken for granted in SF. As is the parallel idea of a single-minded alien culture bent on endless colonization and expansion. But it is a deceptive red herring. It disregards everything we know about how evolution and adaptation work, and how and why human intelligence was a successful adaptation on earth. Humans have the cognitive abilities they do to handle the task of inhabiting new environments, which we do better than any other single species. Or, if you prefer, humans can manage the task of inhabiting new environments because we have the cognitive abilities we do. Whichever way the causality runs, the abilities and the demands are inseparable.

It's reasonable to conclude, therefore, that to manage the task of settling new star systems, any species of alien life form or self-reproducing robot would have to be at least as intelligent and social and adaptable as we are.

So, let's consider what happens when the robots or aliens arrive in a new star system and begin a colony. They can't just run a program or follow the explicit instructions of a sacred book, to tell them exactly what to do next. They have to learn about the environment, locate resources, anticipate hazards, and develop ways to deal with them. Like the Geefle and the Gonk, they have to compensate for being poorly physically adapted to their environment by specializing and socially cooperating. They have to build the means to sustain their lives and nurture their eventual descendants. They have to innovate to suit their environment. They might even have to adapt physically, either by evolution or by deliberate manipulation of the physical characteristics of their offspring.

However things work out, they'll have a society and a culture. They'll have lives. They'll have will and desires of their own. They need to have these things to survive, let alone to have any chance of becoming capable of the next phase of interstellar travel.

At some point, which can happen only long after they've become well adapted to their environment, their civilization may succeed in developing the means to muster the enormous amounts of energy and machinery needed to send off new star colonies of their own. At that point, and thereafter, they will face the same decision their distinct ancestors on their planet of origin faced, and that we might face ourselves someday: should they use those resources on star colonies, or to improve their lives where they already are?

Somewhere within a few hundred light years of us there just might be a planet full of self-replicating machines, who have just taken their every-third-millennium vote on whether to build a ship to send one of them to another star system, or upgrade all their holo-decks again instead. And for the eighteen thousand forty-ninth time, the colony-ship faction got outvoted.
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Old 17th July 2017, 07:33 AM   #45
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Originally Posted by jrhowell View Post
Our intelligence has given us the technological means to wipe ourselves out of existence but not the wisdom to avoid developing that technology. Perhaps other civilizations have fallen into the same intelligence gap.
Another slant on that would be that extinction events are extremely common (including those self-induced), and what makes them only seem not so is the erroneous impression given by short human lifespans. It looks nice out there, but the cosmos can be fatally nasty, with or without prior notice. OTOH, depending on how fast you think Sol is heating and the effect of that on our planet, Earth may "only" have two more galactic rotations left before it is uninhabitable. That's twice the time since the early Permian extinction, so perhaps there is hope for an Earth species yet, even if we off ourselves or get stomped. Future cuttlefish in space!?
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Old 17th July 2017, 07:53 AM   #46
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I would think that one other factor here would be the vast time in which all these events might happen, as well as the variety of reasons. Colonization or invasion is only one of several possibilities for an alien craft to come within view. They might, after all, be some variant life form that breathes methane and likes its cocktails served at boiling temperature and finds earth a poor place to settle. We, as a species, have not been around for all that large a proportion of cosmic time, and there really is a pretty short window of time in which human beings have been both present and able to notice what's going on in the universe. Spacecraft could have flown by a half million years ago, taken a look and left, and we'd never know it. Or maybe they tried to land and crashed. We'd still never know it.

I should think that any calculation of the likelihood of such an event must be divided by the likelihood that we just plain missed it.
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Old 17th July 2017, 10:23 AM   #47
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IMO, it is quite likely that intelligent life is extremely rare. It took approximately half of its habitable life span for the Earth to develop a species capable of producing significant technology. Of course, extrapolating from a sample of one is subject to a lot of error, but it seems entirely possible that there just aren't very many space-faring civilizations around at any given time. If the nearest one to us is on the other side of the galaxy, or in a different galaxy, we will in all probability never find any evidence of their existence, nor they of ours.

Also, as others have pointed out, interstellar travel is extremely difficult and expensive, with few rewards. Although it makes for great science fiction stories, it's very likely that it just doesn't happen much, if at all.
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Old 17th July 2017, 10:46 AM   #48
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Originally Posted by Fudbucker View Post
Why would you think that? Do you think establishing a colony on Mars would require "massive sacrifices"? I think we could fund it without the public sacrificing anything. And eventually, a Mars Colony will be self-sufficient.
We can't even fund the US military without people complaining about sacrifices.

A Mars Colony would not be self-sufficient in any reasonable amount of time. There's no breathable atmosphere. There's no radiation shield. There's no biosphere, no self-sustaining ecosystem. There's no industrial base. All of that would have to be built there, from scratch, using materials and equipment shipped from Earth.

How many people would it take, to have a self-sustaining community? Enough people to ensure that anyone who wanted a family grouping could find one? What about procreation? It's not much of a colony if you have to keep shipping people from Earth to replace the Martians. What's the minimum number of people you'd need, to ensure that everyone who wanted to raise a child, whether alone or in a family grouping, was able to do so? And still have enough surplus labor to get all the other work done? How many people would you need, to ensure that children were being raised at or above the replacement rate? Voluntarily, by willing parents? Over multiple generations? Not everybody who's a good fit for Martian colony work is going to be a good fit for parenting. So you'll probably need a lot of people, to ensure a viable fraction of them are willing and able to be good parents.

Now, how much biomass will you need, to establish a stable, self-sustaining ecosystem that can support that many people? How much of that biomass are you going to manufacture from base elements on Mars, and how much energy will you need to harvest? How much energy harvesting infrastructure will you need just to get started on that? There's no petrochemicals. Solar has challenges. Nuclear might work, but has its own set of challenges. Wind?

And then there's the manufacturing base to build and repair all that manufacturing and harvesting infrastructure. Where does that come from.

On Earth, we take a lot of things for granted. A breathable atmosphere. A magnetosphere that shields us from the worst solar and cosmic radiation. Over a century of established industrial infrastructure. You'd have to rebuild all that infrastructure, with all the reliability and ubiquity that we take for granted, that makes our lives so easy on Earth. And for what? To give people a chance at surviving in an environment that *even with all that* is still more hostile to human life than Antarctica, or the continental shelves.

The way I see it, a Martian colony would probably never become truly self-sufficient. And it would almost certainly never become a profitable trading partner with Earth.
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Old 17th July 2017, 11:22 AM   #49
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Originally Posted by theprestige View Post
....
The way I see it, a Martian colony would probably never become truly self-sufficient. And it would almost certainly never become a profitable trading partner with Earth.
That's just because some liberal doo-gooders have poo poohed the idea of child slave labor camps. We could make America great again if we'd just fix the priorities and defund all that silly science and stuff. Newt Gingrich thought we ought to take illegitimate kids away and put them in orphanages, but he was short sighted and thought we should only colonize the moon. We're growing up and thinking bigger now, folks.
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Old 17th July 2017, 11:38 AM   #50
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Originally Posted by theprestige View Post
We can't even fund the US military without people complaining about sacrifices.

A Mars Colony would not be self-sufficient in any reasonable amount of time. There's no breathable atmosphere. There's no radiation shield. There's no biosphere, no self-sustaining ecosystem. There's no industrial base. All of that would have to be built there, from scratch, using materials and equipment shipped from Earth.

How many people would it take, to have a self-sustaining community? Enough people to ensure that anyone who wanted a family grouping could find one? What about procreation? It's not much of a colony if you have to keep shipping people from Earth to replace the Martians. What's the minimum number of people you'd need, to ensure that everyone who wanted to raise a child, whether alone or in a family grouping, was able to do so? And still have enough surplus labor to get all the other work done? How many people would you need, to ensure that children were being raised at or above the replacement rate? Voluntarily, by willing parents? Over multiple generations? Not everybody who's a good fit for Martian colony work is going to be a good fit for parenting. So you'll probably need a lot of people, to ensure a viable fraction of them are willing and able to be good parents.

Now, how much biomass will you need, to establish a stable, self-sustaining ecosystem that can support that many people? How much of that biomass are you going to manufacture from base elements on Mars, and how much energy will you need to harvest? How much energy harvesting infrastructure will you need just to get started on that? There's no petrochemicals. Solar has challenges. Nuclear might work, but has its own set of challenges. Wind?

And then there's the manufacturing base to build and repair all that manufacturing and harvesting infrastructure. Where does that come from.

On Earth, we take a lot of things for granted. A breathable atmosphere. A magnetosphere that shields us from the worst solar and cosmic radiation. Over a century of established industrial infrastructure. You'd have to rebuild all that infrastructure, with all the reliability and ubiquity that we take for granted, that makes our lives so easy on Earth. And for what? To give people a chance at surviving in an environment that *even with all that* is still more hostile to human life than Antarctica, or the continental shelves.

The way I see it, a Martian colony would probably never become truly self-sufficient. And it would almost certainly never become a profitable trading partner with Earth.
I think because of our easy access to the fruits of our technology and industry we often forget or simply don't realise what is required to produce even our most common products, say a lightbulb. To be self sufficient the Mars colony would need to replicate a huge supply chain for each and every product. For instance it would need to build its own microprocessors, folk should have a look at what a fabrication plant requires.
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Old 17th July 2017, 11:43 AM   #51
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Originally Posted by bruto View Post
That's just because some liberal doo-gooders have poo poohed the idea of child slave labor camps. We could make America great again if we'd just fix the priorities and defund all that silly science and stuff. Newt Gingrich thought we ought to take illegitimate kids away and put them in orphanages, but he was short sighted and thought we should only colonize the moon. We're growing up and thinking bigger now, folks.
Would you mind *not* ******** up this thread with politics? If that's too much to ask, could you at least leave me out of it?

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Old 17th July 2017, 12:29 PM   #52
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Originally Posted by theprestige View Post
Would you mind *not* ******** up this thread with politics? If that's too much to ask, could you at least leave me out of it?

This signature is intended to irradiate people.

Sheeeesh! Did some one wake up a little Grumpy McGrumperstein?!

I think bruto was riffing on the Alex Jones and Martian Slavery thread. I think ...
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Old 17th July 2017, 02:15 PM   #53
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Originally Posted by Elagabalus View Post
Sheeeesh! Did some one wake up a little Grumpy McGrumperstein?!

I think bruto was riffing on the Alex Jones and Martian Slavery thread. I think ...
I was, but I confess I was getting a bit political and that was probably not warranted, but the temptation given the idea of colonies on Mars was too hard to resist. Apologies.

On the other hand, one must remember that a great deal of what gets done or not done in space depends on politics, and one of the other factors here is the potential for an alien civilization to be run by people who, rightly or wrongly, do not find political advantage in the exploration of deep space. It does not matter how curious or how adventurous or how inspired some people are if they are slaves or drones fighting over orts and gleanings.

It seems odd that when we think of the enormous, nearly boundless and mysterious universe, we tend not to imagine the enormous, nearly boundless diversity that it might contain.

The idea of science for its own sake, of sacrificing today's comfort for curiosity about the universe, and so forth, might just be more of a human quality than a universal one. A highly civilized civilization might just be run by people who would rather spend their time and energy growing fine wine, stroking each other's erogenous tentacles, torturing small animals, or more likely doing something unimagined with things unimagined.
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Old 17th July 2017, 06:07 PM   #54
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Originally Posted by Fudbucker View Post
I positt hat planets capable of supporting advanced life are very fragile, and when civs become advanced enough, they invariably disrupt the delicate balances of ecosystems and feedback loops, and quickly render their planet inhospitable for life.
I have already mentioned this possibility in this post/thread

http://www.internationalskeptics.com...6&postcount=12

Having seemingly avoided the "nuclear holocaust" variety of the Great Filter you mention in your opening remarks, it seems like we are making a good fist of turning our own planet into an uninhabitable wasteland. When you consider scale of the age of our planet, even only considering the length of time that mammals have walked the Earth, we have dramatically changed our environment in a heartbeat! I fear we may soon reach a tipping point where things will happen more quickly than we can adapt to, and we'll have no way of stopping it.

Originally Posted by Fudbucker View Post
If these hypothetical aliens can stabilize their birth-rate and stall their growth, no prob. But if they can't, it's going to get more crowded, and people will leave for other planets. And there aren't an infinite number of planets. And yet they're not here. So maybe alien civs have more control over reproduction than we do?
For all intents and purposes, the number of planets might as well be infinite. While life may be prolific throughout the universe, there are almost certainly many times more planets than there are stars. The Kepler Mission has discovered over 4000 candidate stars which might have planets. Of those, over 2300 so far have been confirmed, with over 30 planets being less than twice the size of the Earth and in their star's habitable zone.... and that is all within 9,000 light years.

Furthermore, Kepler is only able to detect planets which orbit in a plane such that they transit across their star from our point of view. Stars are only in the order of a few thousandths of an arc second in apparent diamater, and there are about 1.3 million arc-seconds in a circle, so the chances for any given star, of the plane of its exoplanets orbits being right in line for detection from our location is astronomically small, one in many millions, and yet Kepler has had thousand of detections.

IMO intelligent life is vary rare, and intelligent, technologically advanced civilizations are even rarer still. You only have to look at the sequence of sheer coincidences that occurred which took life on our planet and turned it into us... dramatic climate changes, numerous mass extinctions, super-volcanoes, and the most recent, the Chicxulub asteroid impact that wiped out the dinosaurs 65 million years ago which led to the rise of the mammals and ultimately, to us. No Chicxulub, no intelligent humans, at least, not at this time, and dinosaurs could still be ruling the Earth.

Here's a consideration for you. I posit that there may not be a Great Filter. Maybe there are many intelligent, advanced civilizations out there near us, and there are other reasons why we haven't detected them.

It has long been considered that an advanced civilization will have a Radio Signature, due to the fact that we believe these civilizations must have discovered radio and are broadcasting across a wide range of radio frequencies. But perhaps this is not true at all. On our planet, we have only been broadcasting for 120 years. Once we got going, we were pouring out huge power levels of radio wave in all directions. thousands of Radio and TV stations with power levels up in the hundreds of kilowatts, with hundreds in the megawatt range. Now, however, we are in the process of reducing our Radio Signature. Terrestrial TV stations are being replaced with cable and satellite TV. The use of powerful primary and secondary radar for aircraft position detection decline, its being replaced with GPS. Now Communication and TV broadcast satellites have a power output of between 2Kw and 20Kw but spread out over hundreds of channels, the power of individual channels being as little as 20 watts. a typical GPS Satellite radiates about 25 watts.

It is entirely possible that within 100 years, the Earth's Radio Signature will be almost non existent and not detectable at light-year distances. In our entire human existence on Earth of, say, 1.5 million years, we would only have pumped out detectable levels of RF radiation into space for 200 years - 0.013% of our time here. If this also happens with other civilizations, then the detection window might be very short... if a nearby advanced civilization is technologically 300 years ahead of us, they might no longer be radiating RF into space, and if so, we have missed them.
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Old 17th July 2017, 10:24 PM   #55
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Originally Posted by Darat View Post
But you have to factor in costs of such spacecraft, it would be a resource draining exercise for even a single worldwide organised society.
If Earth were a single worldwide organized society on approximately the same level of development, we would be able to afford the ridiculous costs associated without too much hassle. It wouldn't even need to be all industrialized like the West, average GDP of the world today would be more than enough. The spending on defense alone would easily cover it, not to mention all the resources wasted in pointless petty conflicts, which are pocket change compared to what is going down the drains of corruption in the various swamps from Russia and China to the third world.

In fact if Earth was a single worldwide organized society, I reckon we'd need a project like that to keep ourselves focused and drive the science and technology forward.

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Old 17th July 2017, 10:28 PM   #56
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the more advanced a civilization gets, technologically, the more efficient is its use of energy.
So it is unlikely that they would waste literally astronomical amounts of energy to send signals lightyears into space accidentally: we will not observe the passive emissions of another civilization.
The best hope to detect life would be through anomalies in the atmosphere of exoplanets or to build a Solar Gravity Telescope: both require no emissions from the observer.
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Old 17th July 2017, 10:44 PM   #57
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Originally Posted by smartcooky View Post
IMO intelligent life is vary rare, and intelligent, technologically advanced civilizations are even rarer still. You only have to look at the sequence of sheer coincidences that occurred which took life on our planet and turned it into us... dramatic climate changes, numerous mass extinctions, super-volcanoes, and the most recent, the Chicxulub asteroid impact that wiped out the dinosaurs 65 million years ago which led to the rise of the mammals and ultimately, to us. No Chicxulub, no intelligent humans, at least, not at this time, and dinosaurs could still be ruling the Earth.
There was an argument made that this is irrelevant. The maximum brain to body mass gradually rose with time, meaning an intelligent creature was becoming progressively more likely anyway. No Chicxulub and a human-like species might trace its lineage back to the velociraptor instead of a small mouse-like creature that lived at around the same time.

It's really the age-old dilemma of whether it is relevant that something is a result of a hugely implausible set of coincidences or not. The dilemma is assumed to be false and the fact the set of coincidences was implausible is irrelevant because no prediction was made beforehand is the usual approach. If the assumption is correct intelligent life will arise within a billion years or so of complex life appearing.

Quote:
It has long been considered that an advanced civilization will have a Radio Signature, due to the fact that we believe these civilizations must have discovered radio and are broadcasting across a wide range of radio frequencies. But perhaps this is not true at all. On our planet, we have only been broadcasting for 120 years. Once we got going, we were pouring out huge power levels of radio wave in all directions. thousands of Radio and TV stations with power levels up in the hundreds of kilowatts, with hundreds in the megawatt range. Now, however, we are in the process of reducing our Radio Signature. Terrestrial TV stations are being replaced with cable and satellite TV. The use of powerful primary and secondary radar for aircraft position detection decline, its being replaced with GPS. Now Communication and TV broadcast satellites have a power output of between 2Kw and 20Kw but spread out over hundreds of channels, the power of individual channels being as little as 20 watts. a typical GPS Satellite radiates about 25 watts.

It is entirely possible that within 100 years, the Earth's Radio Signature will be almost non existent and not detectable at light-year distances. In our entire human existence on Earth of, say, 1.5 million years, we would only have pumped out detectable levels of RF radiation into space for 200 years - 0.013% of our time here. If this also happens with other civilizations, then the detection window might be very short... if a nearby advanced civilization is technologically 300 years ahead of us, they might no longer be radiating RF into space, and if so, we have missed them.
Part of the Fermi paradox is that a single self-replicating robot should be able to colonize the galaxy within 2 million years or so. The fact Earth is not a colony of such robots and there are no traces of such presence on Earth tells us no such thing happened since the Milky way was born, many billion years ago. The said robot should be trivial to make with our technology within 100 years and possibly in a fraction of that time.

This implies that either no species similar to ours appeared any earlier than a measly 2 million years ahead of us, or else it didn't start with a project like that. The latter appears more likely and probably requires a great filter of some sort.

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Old 18th July 2017, 12:55 AM   #58
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Originally Posted by McHrozni View Post
If Earth were a single worldwide organized society on approximately the same level of development, we would be able to afford the ridiculous costs associated without too much hassle. It wouldn't even need to be all industrialized like the West, average GDP of the world today would be more than enough. The spending on defense alone would easily cover it, not to mention all the resources wasted in pointless petty conflicts, which are pocket change compared to what is going down the drains of corruption in the various swamps from Russia and China to the third world.

In fact if Earth was a single worldwide organized society, I reckon we'd need a project like that to keep ourselves focused and drive the science and technology forward.

McHrozni
Strongly disagree. It would still be a resource drain of significant amount.
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Old 18th July 2017, 01:11 AM   #59
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Originally Posted by Darat View Post
Strongly disagree. It would still be a resource drain of significant amount.
Right.
Keep in mind that resources used to build spaceships are gone for good: unlike earth-bound projects, we will never get to recycle them.
And given the tolerances required for spaceflight, it will be highly desirable materials that earthlings will have to give up for good.
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Old 18th July 2017, 01:18 AM   #60
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Originally Posted by theprestige View Post
We can't even fund the US military without people complaining about sacrifices.
Originally Posted by theprestige View Post
Would you mind *not* ******** up this thread with politics? If that's too much to ask, could you at least leave me out of it?
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Old 18th July 2017, 01:43 AM   #61
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Originally Posted by Darat View Post
Strongly disagree. It would still be a resource drain of significant amount.
In the sense it would cost a lot, sure. It would also give the society a goal to focus onto, driving development forward. Right now, we have no need for such ambitious projects, we have plentiful conflicts and other sources of pushing development forward. However, if we had a unified worldwide state, we would lose one major component of that conflict, stunting the development and making ourselves more inward looking, which would stunt our development in the long run (>30 years). Short term results could be splendid, long term much less so.

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Old 18th July 2017, 01:46 AM   #62
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Originally Posted by The Great Zaganza View Post
Right.
Keep in mind that resources used to build spaceships are gone for good: unlike earth-bound projects, we will never get to recycle them.
And given the tolerances required for spaceflight, it will be highly desirable materials that earthlings will have to give up for good.
So? Unless the materials in question would be essential to keeping the civilization alive on Earth, this is a minor loss.

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Old 18th July 2017, 02:46 AM   #63
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Originally Posted by McHrozni View Post
So? Unless the materials in question would be essential to keeping the civilization alive on Earth, this is a minor loss.

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you mean in your "global employment-creation" scheme?
I guess it would beat war, a kind of futuristic Tower of Babel project.

But in a balkanized world, the country aggressively embarking on building a generation ship would leave itself vulnerable to those countries purely interested in planet-side expansions.
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Old 18th July 2017, 02:51 AM   #64
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Originally Posted by McHrozni View Post
Part of the Fermi paradox is that a single self-replicating robot should be able to colonize the galaxy within 2 million years or so

You're talking about von Neumann probes.

There are a number of reasons why it is highly unlikely that any advanced civilization would be negligent enough to design and build such probes. Its the "Persian Chessboard" problem; you start with one grain of wheat on the first square of the chessboard, two grains on the second, four on the third, eight on the fourth, etc. By the time you get to square 64, you have 18,446,744,073,709,551,615 grains of wheat. This weighs about 1200 billion metric tons; over 1500 times the current annual global wheat production

They (the advanced civilization) would understand that if each probe makes two probes, and each of those two makes two more and each of those four make two more, probe manufacture would end up consuming all the material resources in a galaxy in a relatively short time, the probes would act like a virus.

Carl Sagan basically put paid to the von Neumann probe theory in his 1997 (final) book "Billions and Billions: Thoughts On Life And Death At the Brink Of The Millennium" The second chapter of this book is actually titled The Persian Chessboard and Sagan wrote that "Exponentials can't go on forever, because they will gobble up everything"

There has been one counter argument that the probes could be designed to limit production, but the problem there is that it would only take one probe to malfunction and ignore/override the limitation and presto, the problem is back... the more probes get made, the more chance of a malfuncntion.

IMO, if advanced civilization did send out such probes., they are more likely to be Bracewell probes or something similar.
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Old 18th July 2017, 03:00 AM   #65
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Originally Posted by The Great Zaganza View Post
you mean in your "global employment-creation" scheme?
I guess it would beat war, a kind of futuristic Tower of Babel project.
Yup. Or the Pyramids, really. Except this project has a more advanced purpose than to serve as a glorified tombstone.

Quote:
But in a balkanized world, the country aggressively embarking on building a generation ship would leave itself vulnerable to those countries purely interested in planet-side expansions.
No question. Endeavors like that would have to be species-wide.

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Old 18th July 2017, 03:09 AM   #66
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Originally Posted by smartcooky View Post
You're talking about von Neumann probes.
Yes, I do.

Quote:
Carl Sagan basically put paid to the von Neumann probe theory in his 1997 (fina)l book "Billions and Billions: Thoughts On Life And Death At the Brink Of The Millennium" The second chapter of this book is actually titled The Persian Chessboard and Sagan wrote that "Exponentials can't go on forever, because they will gobble up everything"
Our own biological blueprint is not all that different from a von Neumann probe. We manage well enough, thanks to an information blueprint that keeps us from going on forever, keeping us of manageable size and dealing with malfunctions. There's no reason a probe can't be designed with those as well. Exponential can't go on forever, but von Neumann probes don't have to go on forever anyway, just enough to scout out the entire galaxy and mark and maybe terraform a few (hundred million) planets for their makers to colonize along the way. It could take two million years or it could take five, but this is still quite a short time on a galactic scale.

Quote:
There has been one counter argument that the probes could be designed to limit production, but the problem there is that it would only take one probe to malfunction and ignore/override the limitation and presto, the problem is back... the more probes get made, the more chance of a malfuncntion.
You can make several kill switches along the way. Our bodies have 6-7 checkpoints to beat cancer. It works ~50% of the time in the modern world. Elephants have one key checkpoint (the p53) built about ten times stronger and it works for them ~100% of the time. If some probes malfunction other probes can also be programmed to destroy them, our own immune systems work in the same way. It should be possible to create a functional system in this way.

In short, it's possible to make the chance of failure low enough to conquer the galaxy in this manner. The probes arrive in a star system, scout out sources of energy and material for self-replication and scout for planets suitable for habitation of their maker and send the information they gathered home. If suitable planets are found some of the probes then proceed with terraforming for the eventual arrival of colonists while others depart for other systems.

Quote:
IMO, if advanced civilization did send out such probes., they are more likely to be Bracewell probes or something similar.
We see none of those either and if one had arrived on Earth within the past, ugh, 10? 100? 500? million years or so it would likely mark Earth as a good place to keep an eye on for signs of intelligent life to arise eventually.

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Old 18th July 2017, 03:30 AM   #67
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Originally Posted by McHrozni View Post
Our own biological blueprint is not all that different from a von Neumann probe. We manage well enough, thanks to an information blueprint that keeps us from going on forever, keeping us of manageable size and dealing with malfunctions. There's no reason a probe can't be designed with those as well.
And look what can happen when just one cell malfunctions in the body.

Originally Posted by McHrozni View Post
Exponential can't go on forever, but von Neumann probes don't have to go on forever anyway, just enough to scout out the entire galaxy and mark and maybe terraform a few (hundred million) planets for their makers to colonize along the way.
If they are designed to replicate on a 2:1 basis (minimum requirement to colonize galaxy - 1:1 will see a diminishing number of probes through losses) then they must go on until they consume all resources

von Neumanns idea was small probes... terraforming a planet requires massive investment in material and time

Originally Posted by McHrozni View Post
If some probes malfunction other probes can also be programmed to destroy them, our own immune systems work in the same way. It should be possible to create a functional system in this way.
Oooh, Non-Sequitor, your facts are uncoordinated. I am Nomad!

Originally Posted by McHrozni View Post
In short, it's possible to make the chance of failure low enough to conquer the galaxy in this manner. The probes arrive in a star system, scout out sources of energy and material for self-replication and scout for planets suitable for habitation of their maker and send the information they gathered home. If suitable planets are found some of the probes then proceed with terraforming for the eventual arrival of colonists while others depart for other systems.
This is very risky. I do not believe an intelligent advanced civilization would take such a massive risk

Originally Posted by McHrozni View Post
We see none of those either and if one had arrived on Earth within the past, ugh, 10? 100? 500? million years or so it would likely mark Earth as a good place to keep an eye on for signs of intelligent life to arise eventually.
We aren't supposed to see them.

If I were an intelligent alien probe, I see nothing in Earths history or behaviour record that would make me want to stick my head above the parapet and say "Hi"!!
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Old 18th July 2017, 03:45 AM   #68
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Originally Posted by smartcooky View Post
And look what can happen when just one cell malfunctions in the body.
In most cases, nothing happens. Well, the cell commits seppuku most of the time, it gets brutally executed in most other cases. In the worst case scenario the body must endure an alien growth which consumes resources until such time as it is no longer able to support it and dies.

Quote:
If they are designed to replicate on a 2:1 basis (minimum requirement to colonize galaxy - 1:1 will see a diminishing number of probes through losses) then they must go on until they consume all resources
They can be designed to replicate on any basis as according to needs and up to a certain limit. If you need 100 probes the probe will replicate to that number. If you need more it will replicate more times, if you need fewer it will replicate less. Why would this be a problem? It can have more intellect than a bacteria cell.

Quote:
von Neumanns idea was small probes... terraforming a planet requires massive investment in material and time
Either use many probes, each doing a small task for a collective massive effort or else equip the initial probe with the ability to build larger systems for larger tasks. The probe system would have hundreds or thousands if not hundreds of thousands of years to work on making the planet habitable, time and resources requirements are not that much of an issue. It will take years, maybe decades for information that a planet is habitable or is going to be made habitable to reach the creator anyway, it will take ten times longer still for the colony ship to arrive, not to mention the time to build the ship (or ships) in the first place. Time is something the probes should have in abundance.

Quote:
This is very risky. I do not believe an intelligent advanced civilization would take such a massive risk
You need to believe no intelligent advanced civilization would ever take such a risk, not even a rogue part of it. This is a tall order, given that the idea has some traction in the only civilization we know of.

Here's the thing, unlike with the space colonization, you don't need a commitment of overwhelming amounts of resources. You need a single probe capable of self-replication that doesn't get destroyed quickly. That's within financial capacity of dozens of individuals around the world right now, to say nothing of various organizations and states. The number on Earth is in hundreds at a minimum. You need to believe not one such entity anywhere in the universe would ever take such a risk.

Given that we have crazies like suicide cults and cults devoted to human extinction, that's a tall order indeed.

Quote:
We aren't supposed to see them.

If I were an intelligent alien probe, I see nothing in Earths history or behaviour record that would make me want to stick my head above the parapet and say "Hi"!!
I suggest you read what the probe is built for in that case.

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Old 18th July 2017, 04:35 AM   #69
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Originally Posted by McHrozni View Post
I suggest you read what the probe is built for in that case.
I have

"A Bracewell probe would be constructed as an autonomous robotic interstellar space probe with a high level of artificial intelligence, and all relevant information that its home civilization might wish to communicate to another culture. It would seek out technological civilizationsĖor alternatively monitor worlds where there is a likelihood of technological civilizations arisingĖand communicate over "short" distances (compared to the interstellar distances between inhabited worlds) once it discovered a civilization that meets its contact criteria. It would make its presence known, carry out a dialogue with the contacted culture, and presumably communicate the results of its encounter to its place of origin. In essence, such probes would act as an autonomous local representative of their home civilization and would act as the point of contact between the cultures."

I'm suggesting that its contact criteria wouldn't include making itself known to civilisations with a track record of waging war on its own species (and still doing so), of raping its own planet, and with a propensity to "shoot first & ask questions later" when confronted with the new or unknown.

As I said, If I was an alien probe (or an intelligent, technologically advances alien) I would not want anything to do with humans at this time.
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Old 18th July 2017, 07:08 AM   #70
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Originally Posted by smartcooky View Post
This is very risky. I do not believe an intelligent advanced civilization would take such a massive risk
You seem to believe that intelligent self-replicating machines are too big of a risk to ever be created. I think that they are too valuable of a potential asset to leave unimplemented.

I think that an intelligent civilization that cared about its own long-term existence would need to take the risk lest some other civilization beat them to it. At a minimum you would want monitoring probes scattered about looking for that type of activity from others so that you could nip it in the bud before it is too late.
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Old 18th July 2017, 07:25 AM   #71
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Originally Posted by jrhowell View Post
You seem to believe that intelligent self-replicating machines are too big of a risk to ever be created. I think that they are too valuable of a potential asset to leave unimplemented.

I think that an intelligent civilization that cared about its own long-term existence would need to take the risk lest some other civilization beat them to it. At a minimum you would want monitoring probes scattered about looking for that type of activity from others so that you could nip it in the bud before it is too late.
How do suppose this self-replication would happen?
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Old 18th July 2017, 07:28 AM   #72
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Originally Posted by McHrozni View Post
...snip...

Here's the thing, unlike with the space colonization, you don't need a commitment of overwhelming amounts of resources. You need a single probe capable of self-replication that doesn't get destroyed quickly. That's within financial capacity of dozens of individuals around the world right now, to say nothing of various organizations and states.
...snip...i
Since we don't have any such thing you are just making wild guesses.
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Old 18th July 2017, 07:43 AM   #73
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Originally Posted by McHrozni View Post
Part of the Fermi paradox is that a single self-replicating robot should be able to colonize the galaxy within 2 million years or so. The fact Earth is not a colony of such robots and there are no traces of such presence on Earth tells us no such thing happened since the Milky way was born, many billion years ago. The said robot should be trivial to make with our technology within 100 years and possibly in a fraction of that time.

This implies that either no species similar to ours appeared any earlier than a measly 2 million years ahead of us, or else it didn't start with a project like that. The latter appears more likely and probably requires a great filter of some sort.

McHrozni
Or the robots broke down, and the builders haven't realised (Homer once said "Lisa, you tried and you failed. The lesson here is - don't even try").
Or they programmed them to only go for certain star systems (there might be ethical reasons or practical reasons we haven't thought of).

Ethical reasons could include:
Imagine you are looking to do a bit of colonising in your galaxy. The planets in question are either:
a. Lifeless, and therefore hostile.
b. Have life on them, and therefore you would either be destroying that life, or you risk being killed by the organic life already there (think War of the Worlds).

In "a", we have the challenge of turning a planet unsuitable to support life for our own colonisation. It would be like turning Mars or Venus into another Earth. Even a self replicating robot would struggle with these scenarios.

Now imagine "b", where you have a planet with life on it. By colonising it, we could be preventing another species from evolving into an intelligent species. It would be like someone coming to Earth 50million years ago and wiping out the potential animals there that could evolve into the next civilisation.

Also, why would a civilisation need to colonise an entire galaxy? Even if it did succeed in terraforming planets with robots that self replicated, why do the entire galaxy? (or the star systems where it would be practical to do so). Remember that birth control is easier than space travel.

Also, we are in an obscure part of the galaxy, as most of the stars that are like ours are far away from us. It could be that they have colonised some of those, but see ours as being too far out of the way to bother with.

These are just some of the scenarios that result in another civilisation existing around this time (however unlikely that is), and not coming into contacting with us.
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Old 18th July 2017, 07:47 AM   #74
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Originally Posted by smartcooky View Post
... Oooh, Non-Sequitor, your facts are uncoordinated. I am Nomad!
That little squirt was nothing compared to Vee-ger!
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Old 18th July 2017, 08:13 AM   #75
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Originally Posted by Darat View Post
How do suppose this self-replication would happen?
Something along the lines of breaking down matter into component atoms and rearranging them into the desired configuration. With advanced enough technology they might even be able to break down and synthesize the desired atoms. It is certainly beyond our current capabilities, but I doubt that it is scientifically impossible.
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Old 18th July 2017, 08:29 AM   #76
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Something that rarely gets brought up in discussions like these is AI. There's nothing special about human intelligence that can't be replicated mechanically, so if we're discussing speculative fiction about robot probes capable of self-replication and spreading at measurable fractions of the speed of light, why not assume they're intelligent? Considering the difficulties of bootstrapping their replication using whatever raw in-situ resources are readily available, I'd even argue they'd have to be intelligent. They aren't self-replicating probes. They're colonists. People. "Artificial persons," as Bishop would have it, but persons nonetheless.

There are big advantages to colonizing the galaxy mechanically, but the biggest is probably hibernation. With no messy biology to maintain en route, machines could just shut down, or slow down, operate minimally, and power back up when the destination is near. Which is one possible answer to the great filter: why go 0.1c? You aren't limited by the normal mortal lifespan. Why not 0.001c? It'll take a millennium to travel one light year, but you've got millennia to spare.

The other answer is to question the assumption that aliens would immediately contact us. We couldn't detect another earthlike civilization even if it was around our closest stellar neighbor, so if they're out there we're relying on them to say hi to us. But why would they? We don't deliberately contact lost tribes among our own species;* we wait for them to reach out to us. It could be that there is no Great Filter, that they are out there, keeping clear of our neighborhood to give us some space for self-determination, and waiting for us to purposefully find them. Call it the 2001 solution.

The third possibility is the very real chance that we're among the first civilizations. The Sun is a Population I star, formed from the stellar remnants of a Pop II star, itself formed from a (theoretical) Pop III star. Neither our sunmother or great-sunmother could have supported life. Their lifespans were too short. Here on Earth, multicellular life started about 500 million years ago, and we've only got a billion more years before our sun gets too hot to support life. It's a short window, and we're lucky to have landed in it.

[ETA] *Well, not at present. In the past we've done plenty of contacting, contracting, conquering, etc.

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Old 18th July 2017, 08:44 AM   #77
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Originally Posted by Beelzebuddy View Post
The other answer is to question the assumption that aliens would immediately contact us. We couldn't detect another earthlike civilization even if it was around our closest stellar neighbor, so if they're out there we're relying on them to say hi to us. But why would they?
We don't just have to rely on radio signals for alien that are that close. We can look for things like waste heat signatures (if they are more advanced than us, it is likely they will use more energy than us, and this would show up in waste heat on a planetary scale). Or artificial light, lighting up their planet. Or just some other pollution - such as metals in their atmosphere you would expect to be there naturally.

Also, there are those that are looking for space ships, in the same way we look for exo-planets.
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Old 18th July 2017, 08:50 AM   #78
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Originally Posted by jrhowell View Post
Something along the lines of breaking down matter into component atoms and rearranging them into the desired configuration. With advanced enough technology they might even be able to break down and synthesize the desired atoms. It is certainly beyond our current capabilities, but I doubt that it is scientifically impossible.
I've often wondered along the same lines, and if there are not "molecular effects" one might find only possible with such fine engineering, some of which could be mind-boggling, one imagines. Just to take something already known, how would an "atomically perfect" magnet act, for example? You might never be able to get rid of it!(?)
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Old 18th July 2017, 08:52 AM   #79
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Originally Posted by McHrozni View Post
In the sense it would cost a lot, sure. It would also give the society a goal to focus onto, driving development forward. Right now, we have no need for such ambitious projects, we have plentiful conflicts and other sources of pushing development forward. However, if we had a unified worldwide state, we would lose one major component of that conflict, stunting the development and making ourselves more inward looking, which would stunt our development in the long run (>30 years). Short term results could be splendid, long term much less so.

You're way underestimating the magnitude of the project.

Consider a one million metric ton colony ship (that's supposedly the mass of the original Enterprise in Star Trek, and it might seem overly large until you consider all the systems and materials needed to survive a deep space journey of at least several decades duration and then support a self-sustaining colony) that can accelerate to 0.1C.

That velocity, by the way, exceeds the maximum velocity ever attained by a manned spacecraft (during an Apollo lunar mission), by about the same factor (8,000) that the velocity of that space capsule exceeds human walking speed.

Assume our colony ship's propulsion system is close to 100% efficient at converting the energy in its fuel into kinetic energy, somehow getting "traction" in empty space as easily as a train does on a track. No such system is known, but we'll be optimistic.

It's easy to calculate the amount of energy required for this maneuver, which by Star Trek standards would be merely pulling the ship out of space dock at low impulse power (swinging past Saturn about twelve hours later).

That amount is a figure about equal to all the energy the entire human race currently generates, from all fossil, nuclear, and sustainable sources, per year. Times about a thousand.

That's assuming the fuel is anti-matter, and thus is of negligible mass compared to the rest of the ship. (A mere 2,800 tons of it, reacted with an equal mass of matter, would be sufficient for the acceleration to 0.1C. Were you thinking something more like two or three "containment pods" of a cubic meter or so each, perhaps looking like glass cylinders filled with some flickering luminous gas? Think again.) If we have to use "conventional" fusion reactors instead, then the mass of the fuel load must exceed the mass of the rest of the ship by a factor of about five to reach 0.1C, multiplying the total energy cost by 3.5.

And, oops I nearly forgot, did you want the colony ship to be able to slow down when it gets to its destination, rather than just wave at some edenic planet as it zooms by? Multiply the fuel load and the energy cost by another 3.5.

That's not an issue with anti-matter fuel, but anti-matter fuel has a different energy cost multiplier: making it. Our current methods of synthesizing anti-matter a few particles at a time are so close to zero percent energy efficient as to defy estimation. But let's assume some miracle of physics and engineering that we can come up with a 10% efficient method. (Let's also assume that the anti-matter can be efficiently synthesized as stable solid matter, anti-tungsten or something similar, so that in space it doesn't require many times its own mass in containment systems.)

Thus either with or without anti-matter fuel, we're therefore now talking, making extremely optimistic assumptions, about ten millennia's worth (at present global usage rates) of energy.

Make the ship one tenth as massive (which might just barely be possible for a colony ship, with hibernation, which also has yet to be shown to be possible) and you're back to a mere millennium's global energy supply again.

(Make the trip one tenth as fast, and the energy figures get more manageable, the requirements decreasing by a factor of 100. But now you're designing a ship for a voyage of centuries or millennia, which introduces a whole different set of deep problems.)
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Old 18th July 2017, 09:10 AM   #80
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Beelzebuddy's post reminds me of the old Kurt Vonnegut novel, The Sirens of Titan, in which the entire history of earth is essentially manipulated in order to provide a spare part for a stranded space ship, belonging to an artificially intelligent robot sent on a mission to the end of the universe. The mission is to celebrate a milestone of its civilization, and the message is a single dot meaning "hello."

I find it always a bit amusing in speculations like this how, like theists in another venue, people assume a being vastly, unimaginably more developed, evolved and capable than we are likely to become in a million years, but it thinks and acts as we imagine we would if we were them.

But we're destructive and disruptive, and there's a good chance we'll destroy ourselves and our environment long before we have a chance to fly to other galaxies. We, being intelligent, assume that intelligence is a worthy, and even a necessary, destination for an evolving species, but is it? From the purely untilitarian standpoint of living and prospering, insects or bacteria are probably more successful than we'll ever be. There could be countless planets in the universe, or even our own galaxy on which life flourishes, but if we miss the narrow time window perhaps they're just as likely as ours to have been inherited by cockroaches.
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