Extra Terrestrial Life

Denerick

I've been watching Carl Sagan's 'Cosmos' series lately, and its spurred me on to do a lot of googling about how likely it is that the universe contains other intelligent life.

Everywhere I seem to look, the old paradox seems to reappear - the reason we are not able to detect other intelligent life is because technological species tend to destroy each other nearly as quickly as when they learn that they have the ability to destroy each other. We may have emerged from the Cold War, but all it takes is for one madman to launch a Nuke, and it would set off a chain reaction of catastrophic proportions. I think this view is rather likely.

On the other hand, maybe intelligent life is so advanced that they are simply indifferent to our presence; they mightn't want to contact us or may be monitoring us as some kind of anthropological experiement, using technology beyond our comprehension. (A la, that famous South park episode where they made 'Earth' into an interstellar TV show!) Or it could be the 'zoo hypothesis', where intelligent life is actively protecting us from exposure to other intelligent life, until we reach a certain technological or societal threshold (Such as an end to poverty/war) a la Star Trek

What do you think? I have practically no knowledge or interest in science, so it would be useful if someone versed in these matters would comment

Myrddin

I think the universe is indeed full of life, but not exactly next door neighbours. Isnt there an imaginary sphere, where all radio waves from Earth since the days of the first waves have been slowly spreading out (100 odd light years?)?

It may be the fact that:

1 - The nearest technologically advanced civilisation is far enough away, that their first radio waves havnt reached us yet.

2 - Their radio waves passed us, while we were dressed in animal skins, and have since advanced their communication techniques, which brings me to 3.

3 - Any space farring civilisation, may have surpassed the lowly radio wave, and are communication with a method we do not have to ability to detect yet.

4 - There may be nothing out there, our planets hospitality is a galactic fluke (Personally dont't believe this).

5 - We have detected the presence of alien life, but the powers that be keep that info on a tight leesh. God forbid the bible was wrong.

6 - We have been observed as an aggresive, warlike species who should be avoided at all costs. Their is racism/hatred inherant at the very core of most humans. As an example, northsiders v southsiders, Dublin folk v country folk, republicans v loyalists, irish v english, white v black v asian v middle eastern. All the powers/superpowers have a nuclear arsenal pointed at each other, we are killing each other every day of the week based on some book(s) that were written thousands of years ago. What a nice populous we have, what would happen it an alien spacecraft were to contact what they percieved as our planets leader (US Pres), imagine the Russian/Chinese/Korean/Indian/Iranian response...

To sum up, I believe point 1 with a smideoning of points 2 & 3.

Standard Toaster

EnterNow kinda sums it up.

I personally believe the shear scale of the known universe hinders us ever detecting life outside our own galaxy.
Consider that the first radio waves emitted from earth, about 100 years ago (travelling at the speed of light) have yet to reach even the nearest galaxy similar to the Milky Way, Andromeda, which lies roughly 2,500,000 million light years away.
Eg in 2,499,900 million years the intelligent life forms on habitual planets there will be picking up those waves and maybe 'I Love Lucy' or Elvis's 'Hound Dog' 50 odd years after Us humans of course will unlikey still be around at that time.

Now there are much smaller galaxies closer to home. Canis Major Dwarf is about 25,000 light years from us and it's the closest neighbouring galaxy to our location in the Milky Way. So, if we decided to send an hello message to that galaxy, we might get a reply 50,000 years later! hardly a great way of making friends.

I think if there are other civilizations out there (and no doubt there are imho), unless they have found a way to communicate & travel faster then the speed of light, they to have come to the same realization as we have.

Here's a great video posted recently to youtube from American Museum of Natural History. Please open it in a HD window though.

https://www.youtube.com/watch?v=17jymDn0W6U

(See the amount of 'space' we have yet to actually fully map)


We truly are a grain of sand on a cosmic beach.
I'll add to this later when I have more time

Prof.Badass

Another thing to bear in mind is that just because a species is intelligent doesn't mean it will ever become technologically advanced. There are a lot of other factors at play.

Aswell as intelligence a species would need to have;

1. The ability to communicate complex ideas.
2. The ability to manipulate objects with ease.
3. A social structure that promotes cooperation rather than competition between members of the group. Widespread monogamy would be one way of achieving this (passing on your genes is almost guaranteed and once a mate is aquired there is no need to compete with rivals for mating privileges), i guess very high levels of genetic simmilarity could be another way. And finally,
4. A sufficient abundance of available resources to become technologically advanced.

When you think about humans it's really coincidental that all these factors came together to allow us to get where we are. Regarding the 4th extra factor, it's weird to think that if some sort of apocolyptic event occured before we invent more efficient renewable energy, we might never be able to get back to where we were ever again.

As an aside, i don't think contact with alien species is a good idea. Better safe than sorry.

Pygmalion

To be honest I think that the speed of light limit alone is enough to ensure we'll never communicate with ET.

Basically I don't believe it's ever been shown that an object with mass can travel above (or even at?) the speed of light, and a lot of scientists tend to believe it's impossible (it would certainly require some crazy sci-fi-esque stuff).
If it is impossible there's no point trying to communicate with a species that may or may not still exist by the time we even detect them, let alone the time our message reaches them (and of course the question of whether we'll exist when they detect our message or when the reply reaches :P).

markfla

Pygmalion wrote: »

To be honest I think that the speed of light limit alone is enough to ensure we'll never communicate with ET.

Basically I don't believe it's ever been shown that an object with mass can travel above (or even at?) the speed of light, and a lot of scientists tend to believe it's impossible (it would certainly require some crazy sci-fi-esque stuff).
If it is impossible there's no point trying to communicate with a species that may or may not still exist by the time we even detect them, let alone the time our message reaches them (and of course the question of whether we'll exist when they detect our message or when the reply reaches :P).

Nope the universe itself expanded faster than the speed of light, travelling within space time within the universe appears to be limited to the speed of light but space time itself can and has travelled faster
http://www.scienceline.org/2007/07/09/ask-romero-speedoflight/