My Name Is Legion wrote:
We likely don't detect this stuff because to the best of anyone's knowledge it exists only as fiction.
How unimaginative and droll...it wouldn't be fiction if we detected it...Von Neuman machines would be inexpensive and efficient, therefore a higher likelihood they may exist--if one is to suggest thousands of life bearing planets and a corresponding number of machine developing civilizations--but may also be hard to detect. They also don't break the known laws of physics.
There are some very bad assumptions here.
First, you are making some quite bold assumptions about life in general:
1. That it exists outside Earth. This is likely, given the vastness of space and recent signs that rocky planets may be quite common. I think there is enough evidence to speculate that simple life forms may have arisen on other planets.
2. That such life sticks around long enough to evolve into more complex life.
3. That such complex life evolves down a path similar to ours, in which it gains intelligence and develops a curiosity about its surroundings.
4. That such life forms structures akin to human civilization, allowing mass cooperation and rapid technological advancement.
5. That such life ever develops any interest in traveling to space, or is even physically capable of surviving it.
6. That such life specifically sets about building things that can go into space, with all the technologies required to enable that.
You're making the very flawed, Trekkian assumption that complex alien life forms would think and behave anything like us, that they would have the same interests, goals, and resources. Maybe they're supremely intelligent--much more than us--but have no ability to manipulate tools because they didn't evolve suitable appendages. They're not going anywhere.
As for Von Neumann probes being cheap... well, how come we haven't sent any out, then? I'd just like to point out that we have no physical machinery today that's capable of self-replication. The very concept is still quite fanciful. I think it may be possible someday--possibly in the next couple decades--but even then, it's still a far cry from making probes that can do it for thousands or millions of generations.
My Name Is Legion wrote:
No, direct and observant. Just because this board is devoted to a space opera doesn't mean we have to play "let's pretend just because" on every subject all the time.
There are enough weasel words there to start a jack-in-the-box factory.
One extrapolation follows the other, the Starseed Project is real, Von Neuman machines are almost possible now in 2012. It doens't make sense to send out people when you can start off exploration with machines. We are finding evidence of a huge number of planets and many that could possibly support life, it doesn't take a more than avg bright teenager to follow such extrapolations to the likely conclusions because they are grounded in real science...you of course, don't really care about that..only in being mundane.
Von Neumann machines are not "almost possible now." Where do you get this nonsense?
Here's a question for you: if intelligent life roughly fitting the parameters, capabilities, resources, and interests of human beings was at all common in the universe, how come we've never seen any evidence of it? Likewise with FTL travel. If it's possible to travel faster-than-light and it requires a level of technology that we can conceive (meaning alien civilizations capable of it should be ubiquitous), we should be getting visitors all the time, or at least detecting some really odd (inexplicable) characteristics in space where there's any FTL going on.
Based on the current evidence, it's quite conceivable that we are the most "advanced" life in the entire universe. Maybe the universe is chock full of life, but none of it has ever become more complex than fungi, except for on Earth.
Even if there are
intelligent alien civilizations, that's no guarantee any of them are contemporary with us, either.
If having a space empire was practical and there existed alien life willing and able to establish one, we'd be living under it right now. Given that we aren't, why not accept the prospect that maybe, just maybe
, those civilizations don't exist, or the means to create and run such an empire are either impossible or so difficult to achieve as to be effectively impossible?
It's not "unimaginative" or "mundane" to say this, either. It is acknowledging that just because we can imagine something to happen, that doesn't mean it actually can
happen. Being able to separate fantasy from reality is something most children learn before the age of 10. Throwing away that distinction as an adult doesn't make one more enlightened. If anything, it makes them delusional.