An interesting read well worth the time, despite no crucial new knowledge in the search for life.

Really? The articles revelation is that SETI was wasting time, searching for life on planets that can sustain it because they didn’t consider the oxygen requirement.

Non-paywalled version of the original paper: https://arxiv.org/abs/2308.01160

It feels like a kind of a parochial and underdeveloped argument though, basically taking it for granted that the only path to a technological civilization is the one that humanity took, and then arguing that that path is intrinsically tied to oxygen.

And there are gasses other than Oxygen that can make flames. For instance look up youtubes of Hydrogen & Chlorine flame. So even if flames are necessary, I'm not convinced that Oxygen must be necessary.

Yeah, I don't see any inherent reason why you couldn't use wind/water/geothermal/solar energy and then electricity to get as far up the tech tree as you like. Or just some other form of chemical energy. Some of the steps sound more annoying or slow, but unclear why they'd be blockers.

> but unclear why they'd be blockers.

Something doesn't need to be a blocker in the small to be blocker at large.

I.e. anything that introduces more friction, or is less efficient, for making progress could hamper technological accumulation.

Clearly for general life on Earth, water was a tremendous enabler - although surely other forms of life without water must be possible - but perhaps much less likely.

Likewise for technology, fire is a tremendous enabler. So much of chemistry and material structure is temperature dependent. Not having a similarly flexible way to adjust heat over a wide range would make vast categories of advances too costly to be immediately beneficial, and therefore much less likely to be explored.

I agree. It's an interesting rationale but statements like these feel biased toward our own human-centric history: "on worlds with oxygen abundances less than 18%, technology will not be possible".

I'm not convinced a clever species couldn't find another route.

How do fishbowl planets fit in here?

Fishbowl planets are something along the lines of: the outer shell is ice, but possibly filled with water, meaning there might be intelligent life that developed and thriving inside the internal ocean, but would likely never have a way to contact us.

But, can a fishbowl planet have underwater volcanos they could use as a heat source to forge tools needed to create more advanced technology? Or do ice ball planets not have a warm internal core?

World building stackoverflow recommends a https://en.m.wikipedia.org/wiki/Solar_furnace with polished parabolic mirrors made of some not ferrous reflective material like obsidian shards.

Between phosphorus being rare and oxygen being n

Between phosphorus being rare and oxygen being needed for fire which is needed for tech (but too much oxygen prevents life from evolving through constant forrest fires) I think the Fermi Paradox has been solved.

Also, our sun is freakishly stable.

We are very, very rare.

The reason that there is exactly enough oxygen to support fire is that life is flammable and burning it uses oxygen...