do you still believe?

[garhkal]

And any civilization that had developed faster than light travel, IMO wouldn't bother with such a backwards race like us..

[thekillman]

There could also be a great time gap. Suppose 50,000 years ago, a civilization rose to spacefaring status only 10 light years away, but died out after 20,000 years. They would never have seen us, as we hadn't arisen yet, and we would never know about them, either.

Some people call it the apes and angels hypothesis.

Basically, if you put the entire history of our planet in the form of the empire state building, then the modern human history would be only a dime on top. If we assume we're halfway through our lifespan and we stay until the sun dies, then we have about an empire state's worth of past and an empire state's worth of future. In other words, if we pick any random slice of that weird tower and use it to represent any random alien planet, we'd either be in the far past or far future and hence we'd find either apes, or angels.

The implication here being that if you reversed this idea, and placed a civilization at any random point in this tower, a civilization like us may already have occurred and died out, or it may yet have to form.


There's also the technology-marches-on argument. We've only started broadcasting recently and we're already moving on to cable-based data transfer. We may not be picking up a lot of alien signals because they only broadcast for a short while and then go mostly silent.


And there's the Great Filter, which suggests that each mass-extinction acts like a filter for intelligent life. If it isn't volcanic eruptions, it may be war (Nuclear or not), asteroid strikes, solar outbursts, gamma ray bursts, rogue planets, you name it. And we don't know what's yet to come.

And any civilization that had developed faster than light travel, IMO wouldn't bother with such a backwards race like us..

FTL probably will never happen. But if it did, then yea i'd expect a species has better things to do, like colonizing the best galaxies.

[aretood2]

Some people call it the apes and angels hypothesis.

Basically, if you put the entire history of our planet in the form of the empire state building, then the modern human history would be only a dime on top. If we assume we're halfway through our lifespan and we stay until the sun dies, then we have about an empire state's worth of past and an empire state's worth of future. In other words, if we pick any random slice of that weird tower and use it to represent any random alien planet, we'd either be in the far past or far future and hence we'd find either apes, or angels.

The implication here being that if you reversed this idea, and placed a civilization at any random point in this tower, a civilization like us may already have occurred and died out, or it may yet have to form.


There's also the technology-marches-on argument. We've only started broadcasting recently and we're already moving on to cable-based data transfer. We may not be picking up a lot of alien signals because they only broadcast for a short while and then go mostly silent.


And there's the Great Filter, which suggests that each mass-extinction acts like a filter for intelligent life. If it isn't volcanic eruptions, it may be war (Nuclear or not), asteroid strikes, solar outbursts, gamma ray bursts, rogue planets, you name it. And we don't know what's yet to come.



FTL probably will never happen. But if it did, then yea i'd expect a species has better things to do, like colonizing the best galaxies.

Then not all intelligent life would need to or want to go to space or invent a radio. Another issue is that our star is pretty young. If a race cracks FTL, they could colonize the entire galaxy between the time we developed our first tools to the time we landed on the Moon. So that really makes it rather unlikely that FTL has been developed...unless it was developed so long ago that they have come and gone completely. Fermi's Paradox and all (And yes, I know it is a bit of a misnomer)

[Annoyed]

Any species that has developed FTL (and I do think it's possible, we just don't know how, not surprising, as we are infants in this game) would very likely be able to keep their visits here a secret from us, if they wished to. So Fermi's Paradox means nothing.

We may someday prove the existence of extraterrestrials, either by contact or finding evidence that that they left behind. But we can never prove there isn't such life. At best, we would be able to say we haven't found such life.

[epg20]

there is one thing that was left out, something I heard of a while back, that is, un less the signal is strong enough, there is no way it could get past the helio sphere, the energy field generated by our sun, it is said that our signals will be so scrambled that it would get lost in the background radio signals of the universe, maybe if we set ALL of the transmitters on earth, from ipads to cell towers to tv transmitters to radio telescopes even our orbiting satellites, to transmit on all known frequencies for a month, it might get past it, but if they were ever therewho knows if they would even listen.

[garhkal]

OR whether they could even intercept and decipher them..

[thekillman]

Then not all intelligent life would need to or want to go to space or invent a radio. Another issue is that our star is pretty young. If a race cracks FTL, they could colonize the entire galaxy between the time we developed our first tools to the time we landed on the Moon. So that really makes it rather unlikely that FTL has been developed...unless it was developed so long ago that they have come and gone completely. Fermi's Paradox and all (And yes, I know it is a bit of a misnomer)

Actually no. Just with regular light-limited travel and without extreme technological inventions, a race could colonize the galaxy in a few million years. Which is a lot, but not that much on a cosmic timescale.

Secondly, it's indeed a legitimate alternative that by the time a certain level of technology for interstellar travel is achieved, species simply chose to stay home. Build some sort of dyson swarm and simulate complex worlds rather than trying to colonize them.

Any species that has developed FTL (and I do think it's possible, we just don't know how, not surprising, as we are infants in this game) would very likely be able to keep their visits here a secret from us, if they wished to. So Fermi's Paradox means nothing.

Considering that FTL would require throwing out the laws of physics as we know it, then yes. I mean, everyone always mentions wormholes but nobody mentions that the moment you throw matter (any matter) into a wormhole, it instantly collapses.

That being said, sufficiently advanced aliens may as well be russel's teapot, so i don't really think it matters to the discussion here. Regular species that operate within the bounds of physics as we know it could have all sorts of reasons not to show up.

there is one thing that was left out, something I heard of a while back, that is, un less the signal is strong enough, there is no way it could get past the helio sphere, the energy field generated by our sun

While there's some logic to that, keep in mind that the voyagers are past that heliosphere and we get their messages just fine. Sure our leaked-out radiowaves may not carry a whole lot of information beyond 50 lightyears or so, but that doesn't mean we can't send signals designed to be sent or picked up. And a single purpose-built antenna would be far more useful than using all our devices together.

[Annoyed]

Considering that FTL would require throwing out the laws of physics as we know it, then yes. I mean, everyone always mentions wormholes but nobody mentions that the moment you throw matter (any matter) into a wormhole, it instantly collapses.

That being said, sufficiently advanced aliens may as well be russel's teapot, so i don't really think it matters to the discussion here. Regular species that operate within the bounds of physics as we know it could have all sorts of reasons not to show up.

That's the kicker, isn't it? "The laws of physics as we know them".
We are only a tad over 100 years since the first manned, powered flight. Well below a hundred years since the first use of atomic energy.

We are babes in the woods when it comes to this sort of thing. At our level of development, it would be arrogance in the extreme to declare that FTL is flatly impossible. Sure, it may seem impossible with our current understanding of physics.

That may simply mean that we need to develop a better understanding of physics. We can't possibly say it's impossible any more than a caveman from thousands of years ago could possibly say we could never hope to fly to that bright ball in the night sky. Neither one would know what they're talking about.

[aretood2]

That's the kicker, isn't it? "The laws of physics as we know them".
We are only a tad over 100 years since the first manned, powered flight. Well below a hundred years since the first use of atomic energy.

We are babes in the woods when it comes to this sort of thing. At our level of development, it would be arrogance in the extreme to declare that FTL is flatly impossible. Sure, it may seem impossible with our current understanding of physics.

That may simply mean that we need to develop a better understanding of physics. We can't possibly say it's impossible any more than a caveman from thousands of years ago could possibly say we could never hope to fly to that bright ball in the night sky. Neither one would know what they're talking about.

While I agree on that point, I guess the thing is that we can speculate six ways to Sunday on what might be possible. But based on what we know to be possible, our options are different. It's just a matter of picking which discussion we want to have. If we stick to what we know to be possible (or rather strongly believe) then FTL has one small problem. Causality. Go faster than light, and stuff starts happening with time and it gets rather complicated.

But if we discuss what might be possible, then we can talk about FTL in the hypothetical which makes the discussion all that much more complicated and full of uncertainty.

[garhkal]

Considering that FTL would require throwing out the laws of physics as we know it, then yes. I mean, everyone always mentions wormholes but nobody mentions that the moment you throw matter (any matter) into a wormhole, it instantly collapses.

And who's to say what WE know about physics is not wrong??

[Gatefan1976]

And who's to say what WE know about physics is not wrong??

It's far more likely that our knowledge of physics is more likely incomplete rather than wrong.

[epg20]

As Jodie foster said in the film, "Contact".
Ellie Arroway: [to a group of children] I'll tell you one thing about the universe, though. The universe is a pretty big place. It's bigger than anything anyone has ever dreamed of before. So if it's just us... seems like an awful waste of space. Right?

and
Ellie Arroway: You know, there are four hundred billion stars out there, just in our galaxy alone. If only one out of a million of those had planets, and just of out of a million of those had life, and just one out of a million of those had intelligent life; there would be literally millions of civilizations out there.

yes, but that doesn't mean that we aren't the only life in the universe.

[Annoyed]

But if we discuss what might be possible, then we can talk about FTL in the hypothetical which makes the discussion all that much more complicated and full of uncertainty.

But since we can't say FTL is impossible, that's the discussion we are left with, no matter how messy it gets.

[maneth]

I think it's far more likely that if we're ever visited by aliens, they'll be AI robots of some kind with an effectively unlimited lifespan.

[garhkal]

yes, but that doesn't mean that we aren't the only life in the universe.

I was agreeing that it is very likely we aer not alone in the universe..