Scrutable

Read them here: https://itsonlychemo.wordpress.com/2020 ... i-paradox/

I like the notion that even if intelligent alien life were to visit us here on Earth, we might not recognize it.

I like 8. Here we are, watching Star Wars...

9 is fun too. Probably some other hurdles to overcome first though.

29 "Nobody has visited because they’re all too far away; it takes time to evolve a species intelligent enough to invent interstellar travel, and time for that species to spread across so many worlds.’"

gets my vote

As Douglas Adams says

Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.

"Intelligent enough to invent interstellar travel" assumes interstellar travel is possible. But it likely isn't. Not for species like us.

Space belongs to the robots, not the lifeforms. Maybe it's possible for robots to make journeys of a thousand of years? But why would they want to? What's in it for them?

My guess is that a species got clever and explored its solar system a bit, before deciding on a better way to spread life across the galaxy - panspermia. It designed spores and mechanisms for blasting them out across space. Do that for a few million years and the seeds will be out there, waiting for new stars to form and then drifting down to a rocky planet. It would be a fun thing to do. Like planting an arboretum for long after you're dead.

Artificial panspermia would explain a lot. Earth got life almost immediately, and probably repeatedly when it was sterilised a few times and restarted.

Alternatively, we are the freak first. And it is us who will invent panspermia and sow seeds on planets that won't form for a billion years.

Yes, space is big, and travelling at a significant speed through it is difficult while warp drives and that are impossible, but it's an extremely egocentric universeview to imagine that life on other planets should somehow aspire to be intelligent in the same way humans are.

Most of the life on *this* planet isn't intelligent in that way. I would expect that there's microbial (or similar) life all over the place.

shpalman wrote: ↑

Tue Jan 21, 2020 9:44 am

Yes, space is big, and travelling at a significant speed through it is difficult while warp drives and that are impossible, but it's an extremely egocentric universeview to imagine that life on other planets should somehow aspire to be intelligent in the same way humans are.

Most of the life on *this* planet isn't intelligent in that way. I would expect that there's microbial (or similar) life all over the place.

I am absolutely sure there is other life out there. I just don't believe any of it has visited us or is likely to any time soon.

We have been sending out radio waves since only 1895 so have possibly been picked by aliens up to 125 light years away.

We have not managed to travel even a fraction of that. Unless warp/wormhole technology is possible the universe is just too big for aliens to come a knocking.

lpm wrote: ↑

Tue Jan 21, 2020 9:41 am

"Intelligent enough to invent interstellar travel" assumes interstellar travel is possible. But it likely isn't. Not for species like us.

Space belongs to the robots, not the lifeforms. Maybe it's possible for robots to make journeys of a thousand of years? But why would they want to? What's in it for them?

My guess is that a species got clever and explored its solar system a bit, before deciding on a better way to spread life across the galaxy - panspermia. It designed spores and mechanisms for blasting them out across space. Do that for a few million years and the seeds will be out there, waiting for new stars to form and then drifting down to a rocky planet. It would be a fun thing to do. Like planting an arboretum for long after you're dead.

Artificial panspermia would explain a lot. Earth got life almost immediately, and probably repeatedly when it was sterilised a few times and restarted.

Alternatively, we are the freak first. And it is us who will invent panspermia and sow seeds on planets that won't form for a billion years.

I think that is the key point. Why bother? If possible, it's a stonkingly expensive and difficult thing to do, the resources required are insane. To what benefit? How do you convince a biological civilisation to do something that doesn't benefit anyone alive for thousands of generations? What benefit to a robot civilisation?

Sooner or later, humans will invent cryostorage and load up huge interstellar space-going arks of people desperate to flee the horrors of 24/7 reality TV. And they will never point their comms dishes backwards ever again.

This may be of interest, though it's pretty dense stuff
On the history and future of cosmic planet formation
https://academic.oup.com/mnras/article/ ... 11/1046202

Interesting dating of 'oldest' impact crater event, suggests possible causal relationship with the end of a Snowball Earth period.

https://www.bbc.co.uk/news/world-australia-51201168
paper
https://www.nature.com/articles/s41467-019-13985-7

Relevance here is that we believe that life began early, but remained "primitive" for billions of years. The suggestion that a single random event can give rise to the global disruption that opens new niches that evolution can take advantage of is interesting.

Hmm.

There were multiple snowball earths. There's a pretty straightforward mechanism for why they end - volcanoes pump out CO2 routinely, the ice cover prevents CO2 in the atmosphere reacting with rock, CO2 builds up to ultra-greenhouse levels and melts the ice. The rock is then exposed and removes the CO2 and the cycle repeats.

I suppose an event like this could have accelerated a cycle. But it's pre oxygen, pre Cambrian, so wouldn't appear to be significantly linked to evolution events.