I doubt aliens would be immediately hostile to Earth, there would be no point. Our technology level would be much lower than theirs (probably) and we would have essentially nothing they want. They're not going to come from interstellar distances to steal our oil...
We only categorize certain things as "pollutants" because they are undesirable for us, or for other native life forms.Okay, but what if its not oil they want? What if they want a planet that has liquid water, and can sustain organisms that require oxygen?
Not to mention, humans are disgusting creatures who pollute and destroy everything. If I came to this planet looking for somewhere to colonize, the first thing to go would be humans.
We already have the ability to transmute elements. Every time two particles are smashed together in an accelerator they convert their kinetic energy into mass producing more more particles then they started out with. However, the more massive and complex elements from iron on up require outrageous amounts of energy found only in the most energetic supernovas. The cost and technology required to produce the same results safely anywhere near the earth and with any appreciable quantity is simply beyond the astronomical. We're talking about something like a synchrotron the size of the solar system powered by a black hole.
In comparison a robotic factory capable of crossing a few tens or hundreds of light years is primitive technology with almost negligible costs.
There are far more interesting things than ants, and yet we still study ants.I agree with Michio Kaku on this: if aliens could travel across the galaxy, then they're far far more advanced than us. Them to us is like us to ants. We don't go up to ant hills saying "I've come to bring you technology, to share our secrets." For the most part, you ignore them. Maybe put a few under a microscope and examine them. Maybe just step on them if they get in your way.
Why would they necessarily be curious about us, as the OP claims? If life is widespread throughout the universe, certainly there are more interesting things than us. But, the OP apparently shares that conceited characteristic of the human species: we're the best thing this universe has ever seen. Why wouldn't they want to visit us and give us all their technology?
It's possible, but I don't think it's as likely enough to declare that we should "fear aliens" and try to "avoid contact with them."The aliens may well not have the same notions of mortality or individual preservation as we do. Maybe they wouldn't think of a multi-generational ship as a big deal. "So the ones who launch with it will be dead by the time it gets where it's going. So what?" Or maybe they will have the ability to enter a state of suspended animation more easily than us, whether it's brought on naturally or artificially.
And that may well be the case - for our species.
Evolutionary influences from the past have great influence on our daily behavior, including our tendency toward stagnation without some significant competing motivator. Maybe another sentient species wouldn't have such influences, or maybe they'll have gone to the extent of modifying their own genome (or whatever it is they've got) to tweak some of these behaviors, for better or for worse.
And maybe there's an alien LulzSec group out there who just likes to troll the rest of the galaxy by occasionally screwing with the development of other star systems. One system is broadcasting signs of primitive sentient life? Time to see how they cope with some stress - send a pod to the broadcasting planet with a few billion self-replicating nanobots, whose sole purpose is to consume the planet and turn it into a giant trollface.
It's possible, but I don't think it's as likely enough to declare that we should "fear aliens" and try to "avoid contact with them."
i was thinking about much further in the future than you are, survival of our species.
For the most part, you ignore them. Maybe put a few under a microscope and examine them. Maybe just step on them if they get in your way.
Better now?
I see it like the history with Europe vs American Indians or Europe vs the Australian Aborigines.
while they are similar, the tech levels where different and generally, one did not care about the other until something happened, in which case voilence was the "common" language.
or the ultimate end game, the sun explodes/dies.
for long term survival, getting out of this solar system is a must.
Too many eggs in one basket.
This is nothing like that. Where the Europeans and Indians or whomever else were vastly different culture wise they at least recognized each other as human with human needs and desires. You know how a person thinks. You can anticipate their faults. You each know that there is potential for common ground (trade, sex, violence, etc.). Meeting an alien species for the first time would be nothing like that because the likelihood that we'd have anything remotely in common with them is so far beyond imagination that it's almost impossible to comprehend.
I'm not trying to be a debbie downer or anything here but really, there are so many variables within evolution that can determine the outcome of a sentient species that to try to assign human traits, characteristics, values, etc. is not advisable. What we see as reprehensible and violent are viewed that way because of how we evolved. Who's to say an alien intelligence would understand it the same way? You might think killing a whole biosphere for its resources is wrong but an alien might not even understand that concept. What Stephen Hawking was trying to say (that I've already said) is that it's safe to assume the worst. It's not being shortsided or pessimistic or close minded. It's being smart.
This isn't like Christopher Colombus discovering the New World. It's impossible to predict how a first encounter might turn out when there's no basis for even understanding how that alien species even came into being, especially if they'd be sophisticated enough to reach us. People are willing to risk the continuation of our species because they think it'd be a good idea to say hi to E.T. People see movies like Close Encounters of the Third Kind or Contact and they see that as realistic. I just don't agree with it at all. It makes for good drama but it's wreckless. Isolationism might be the smartest thing we can do in this case.
Why is this so hard for people to accept?
What could we possibly have on this planet that an alien species capable of crossing galactic distances couldn't get a lot easier?
I agree with Michio Kaku on this: if aliens could travel across the galaxy, then they're far far more advanced than us. Them to us is like us to ants. We don't go up to ant hills saying "I've come to bring you technology, to share our secrets." For the most part, you ignore them. Maybe put a few under a microscope and examine them. Maybe just step on them if they get in your way.
Why would they necessarily be curious about us, as the OP claims? If life is widespread throughout the universe, certainly there are more interesting things than us. But, the OP apparently shares that conceited characteristic of the human species: we're the best thing this universe has ever seen. Why wouldn't they want to visit us and give us all their technology?
I'm pretty much on board with this point of view. If some super advanced alien race saw Earth, the most likely scenario is that they might study it for a little bit and then move on. I can't imagine it would be that interesting if the universe has lots of life (e.g. millions of other races out there but too far away to communicate). There's also no indication that we could actually communicate at all. They may have evolved into telepathy or hive mind or something else a long time ago. The wavelengths that we can process, light/sounds/audio/etc. may not be visible or audible to them and vice versa.
Sure, there are a handful of people in the world who keep ant farms and interact with them, but for the most part, you just ignore them unless they really get in your way. With the vast size of the universe and how much space we take up in the universe, we're not getting in the way of anything. Maybe a pet Earth as someone's holiday gift.
"Many" is a subjective term."When men began to increase in number on the earth and daughters were born to them, 2 the sons of God saw that the daughters of men were beautiful, and they married any of them they chose. 3 Then the LORD said, My Spirit will not contend with man forever, for he is mortal ; his days will be a hundred and twenty years. 4 The Nephilim were on the earth in those daysand also afterwardwhen the sons of God went to the daughters of men and had children by them. They were the heroes of old, men of renown." (Genesis 6:1-4)
Many maintain that humankind not only has long ago since been visited, but that ETs are involved in human genetic makeup.
http://en.wikipedia.org/wiki/Ancient_astronauts