Milky Way not unusual, astronomers find | Hacker News Reader

Milky Way not unusual, astronomers find

phys.org

24 pointsdnetesn11 comments

I always find it interesting that people expect Human existence, and therefore the environment for its emergence, is somehow atypical. I don't know the math, but I would have thought by definition, one would wager on it being typical.

People are desperate to believe that something makes them special.

Probably the reason most marketing works :)

In your view, what would it mean to be special?

Only having a sample of one makes it very hard to say for sure.

Let's say sapient life is very common and the vast majority of such species live on fairly similar planets in similar galaxies. In that situation, you would expect a random sample of one species to be typical.

On the other hand suppose typical planets in typical systems are generally very hostile to evolving sapient life. Only very unusual circumstances can lead to suitable conditions, but there are many, many different ways that can happen and different untypical conditions that can lead to sapience arising. Well, then a sample of one simply can't tell you anything about typical sapient species, because there's no such thing.

Looking at our conditions, I think there are worrying signs that out specific conditions are actually very unusual. Almost none of the extra-solar planetary systems we've found look much at all like our solar system. Furthermore we have a weirdly large moon relative to the size of our planet, which has had a huge effect on the tectonic and atmospheric development of our planet. Historically our global climatic conditions have oscillated quite widely, but always somehow managed to escape falling permanently into an extreme state. All of this seems to be very unlikely and atypical.

In the same way, each individual think himself as atypical. Like if our own narrative, what we think ourself about ourself, was de facto a teratology.

Under some models, there’s a non-negligible chance that humans are atypical. See this paper by Sanders, Drexler, and Ord, for instance.

https://arxiv.org/pdf/1806.02404.pdf

Note that this relates to its collision history not being special as it relates to thin/thick disk. I believe the Milky Way is still thought to be atypically large for a spiral galaxy, well above the median size. It's small compared to the large ellipticals like M87 but they are relatively rare. Be proud that we live in a major spiral!

Inspection paradox? https://towardsdatascience.com/the-inspection-paradox-is-eve...

Except for all the people, anyway.

Well, as far we know

well, that's a relief.

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