Probably the most interesting book i’ve listened to in a long time. A definition of life that doesn’t have a thousand edge cases.
Take any object that exists and try to count the number of steps it would take to assemble that object from physical realizable steps. Objects with many copies and larger assembly numbers could be a better definition of life.
https://books.apple.com/ca/audiobook/life-as-no-one-knows-it-the-physics-of-lifes/id1720088951
Sara Imari and Lee Cronin have had some fascinating discussions about assembly theory on various podcasts. Check out their episode on the Lex Fridman Podcast.
They are both awesome - it is a shame the scientific community rejects them.
Personally, I feel like having many copies and large assembly numbers are necessary but not sufficient conditions for life. To me, implying that an iPhone is alive seems to be missing the point, but I could very much see coming up with a new word that represents life and its stuff. That said, if I remember correctly, she also talks about the need for evolution which could enable distinguishing between us and our stuff, but that would add some messiness that you understandably don't want, and I still don't love it as a definition since it still feels more like a test than a definition. Too much of a "shut up and calculate" vibe for me 🙂
I think the iphone would have a much lower assembly number than a person. She mentions an objects assembly number is defined by the minimal possible number of steps to create it, not just how we came up with the object in a particular case, so I don’t think you add the biological entities assembly number to it? An iphone would be a much smaller assembly number compared to humans if so.
The copy number is an important aspect as well that maybe I haven’t gotten to fully reading yet. I would guess the iphones copy number is also quite low in comparison to the number of DNA based lifeforms that have ever existed.
Some combination of copy and assembly number give you a point in life-object space if i am reading correctly so far.
Realistically, you're right about an iPhone having a much lower assembly number than a person, but that makes me curious how an iPhone would compare to a bacteria, but to a point you rightfully made, there are incomparably more bacteria than iPhones. Also, while I'm tempted to think of something like a phone as having a high assembly number given the complexities of things like screens and ICs, realistically once you have one pixel and one gate, scaling things up by 1e6 or 1e9 makes manufacturing quite a bit trickier, but doesn't innately increase the assembly number. On the other hand, I suppose that a single bacteria which is made up of a bunch of organelles, each of which is going to be made up of a bunch of specialized molecules is going to have a lot of unique things rather than many copies of a few things, so I suppose it does seem plausible that a bacteria could have a vastly higher assembly number than a phone in addition to its higher copy number.
I’ve been wanting to read up more on assembly theory for a while. Thanks for the recommendation!
Sounds like a metric that is a proxy for “whoa there is some different sort of shit going on here”
Cool title! ⚛️ 🧬
