[mr_mitm]

Thanks, I read that part before I shared it. It's pretty clear to me, these are pretty well defined quantities, just hard to measure. What is unclear is perhaps the definition of life. But at no point does it assume a planet must be in the Goldilocks zone. So perhaps you want to point out those assumptions you are talking about to me, because I don't see them.

Edit: the parent post has been edited substantially after I replied.

[buran77]

> these are pretty well defined quantities, just hard to measure.

They are "defined" conceptually, in words, not in physical quantities. It assumes we can assign a known value to any of that when we don't and likely never will. It's like saying "Let X answer the unanswerable question. X is the answer".

> at no point does it assume a planet must be in the Goldilocks zone

You could say it implies it with fl.

> Edit: the parent post has been edited substantially after I replied.

Only for legibility.

[the_af]

How can you extrapolate those terms from a single planet with known life without making assumptions?

[mr_mitm]

I can't, but the equation itself doesn't to that. The assumptions are up to the reader to make. That's why I think that the equation isn't particularly useful.