That is functionally the same as being alone in the universe. If we never find any evidence of any other civilisation in the universe, then we are too far away from any aliens to be affected by them.
This is one of the most likely solutions to the Fermi Paradox, but far from being the only one.
Believing without (or dispite) solid evidence sounds like religion to me. Not my bag.
Thinking that Humans are special sounds like religion to me. Not my bag.
It’s not a value judgement on “specialness” it’s about being objective about (possibly uncomfortable) facts.
I would very much like for their to be other ETIs in our galaxy. It just doesn’t appear to be the case.
That’s because we are blind, not necessarily because there is nothing to see…
How do you know that?
Well, it’s patently obvious that our ability to see objects in the galaxy is, to be generous, primitive.
We don’t have the ability to detect another civilization such as our own if it was on a planet orbiting the nearest star.
You’ve said that before, and I think you’re wrong. We’ve measured the chemical composition of a planet 65 light years away - artificial compounds in the atmosphere of a planet around Alpha Centaurus would be detectable, and interpretable as an indication of a technological civilization.
I don’t think humans are any more special than cats, rats, bats or platypuses. It is our planet that is unique… until there is evidence to the contrary.
Is this another belief?
Cite?
Would you accept an answer of “I just believe it”?
Believe whatever you want…
Again, the chance of any two civilizations being close to human levels of progress is infinitesimal, let alone multiple civilizations.
I am confused. You keep saying that it is a matter of belief, but you ask for a cite when facts are presented.
The Hubble Space Telescope has detected carbon dioxide on a planet orbiting another star. The star in question is HD 189733 (also known as V452 Vulpeculae, a variable star designation), a binary system over 60 light years away, and the planet is approximately the size of Jupiter (called HD 189733b). The exoplanet is already known to contain water and methane molecules from previous Hubble and Spitzer campaigns, but this is the first time CO2 has been discovered
What makes you think multicellular life is an inevitable evolutionary step?
Here’s a paper on detection of NO2 in exoplanet atmospheres. With current telescopes signals of anomalous NO2 could be made out to 30 light years.
This seems to be the clincher. Human civilisation will not continue to exist at a 21st century level of technology for much more than a century; either our civilisation will collapse, or we will continue to progress, potentially for thousands or even millions of years. A civilisation with technology a million years in advance of our own may be easily detectable, especially if it produces lots of waste heat. There have been a number of searches for waste heat signatures with no results - I expect we may find some signatures of this kind in due course, but there do not seem to be any in nearby systems.
Other potentially detectable signatures from an advanced civilisation would be radar transmissions, assuming the civilisation has the desire to protect itself against rogue asteroids or unfriendly intruders. Communication transmissions between distant locations within the home system or with probes in surrounding systems could also be detectable in some circumstances. I sometimes wonder if the ‘Wow!’ signal was some kind of probe telephoning home, and we were just coincidentally in the way.
Agreed, but I would go further.
We aren’t only looking for things that we can conceive of, but anything whatsoever.
Imagine that there was some helical structure at the edge of our galaxy that was emitting a complex, non-repeating pattern of gamma rays. It would be good evidence of ETIs (it would at least make us consider the possibility) even while we would have no idea of its purpose.
But, we don’t see Dyson swarms, we don’t see heat signatures and we don’t see gamma helixes…we don’t see anything at all. Which of course doesn’t rule out advanced ETIs, but it should absolutely make us more pessimistic about how many there might be.