Do you believe in UFOs & flying saucers ?

Strazdas wrote: »

Problem with the UFO theories is that any advanced civilisation would be so far ahead of us that they would surely have the technology to make themselves invisible. We think of aliens in too lateral terms and as if they would have the same levels of intelligence as us : if they could travel across galaxies at speed (or send remote controlled vehicles here), they would be way ahead of humans in intelligence.

Strazdas wrote: »

But in that case, we wouldn't even be able to see them (unless they wanted us to see them). They presumably would have the technology to make themselves invisible to the human eye. They could even be here among us and we wouldn't have a clue.

NeuralNetwork wrote: »

It's a bit depressing to think that if we do eventually detect another civilisation, for example if SETI picks up some kind of signal or just noise that is unequivocally from an alien intelligence, it's very likely that it will be so far away that we will simply never be able to return it.

It could well end up that we know there's something out there somewhere, but that all we ever see is some radio or other EM wave transmission or noise from some artificial process from perhaps hundreds of thousands or even millions of years ago. It could even be a civilisation that long since disappeared.

I would suspect there's a strong possibility we'll find life in the solar system too, but it'll be something like pond scum on one of Jupiter's moons. It would still be an enormously big break through that would mean that we could at least know that perhaps life is a lot more common a phenomenon than just some freak accident on Earth, but it isn't likely that it will lead to any chats.

The whole Star Trek type idea of alien civilisations that all just have slightly different foreheads is entertaining, but that's all it is. It has more in common with our own history of earthly exploration and discover, odysseys into unknown parts of our own planet, than it has with any kind of possible reality.

If we were to ever encounter any kind of life from elsewhere it could be completely unrecognisable to us or at least extremely unlikely to be able to interact with us.

It could also be tiny or huge depending on how scale works. It might be entirely artificial intelligence.

Then you also have to consider that we exist as part of an extremely interconnected planetary scale biological system that has co-evolved with us. So, there's no reason to assume that either our microorganisms like bacteria, fungi and similar, or alien equivalents wouldn't simply just see "yum yum raw materials!" and destroy the biology from the other system. It's quite likely that we'd have no defenses in the form of evolved immune systems against some alien microbes deciding that your building blocks were dinner and the same could well happen the other way around too.

I mean imagine we go visit the Klingon homeworld and they're all turned to sludge by something as innocuous as the mould from a cheese sandwich.

Then if you take something 'simple' like food. We eat plants and animals and have complex systems that are evolved to process them down to sources of raw materials and energy.

If you had to eat something that had evolved somewhere else, it could be as useful to you as eating plastic as there wouldn't necessarily be any recognisable or useful proteins or amino-acids or any of those things.

Before all of that, you also have to get past the seeming impossibility of going faster than the speed of light, which, certainly with our current understanding of physics, is impossible if it behaves as predicted in Einstein's Theories of Relativity.

So, all in all it seems highly unlikely that sitting down and having chats with aliens is very likely anytime soon.