Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "Angela Collier " channel.

  1. I guess it depends on what you call alien. I would define "life" as anything that self-replicates and has evolution (no matter how slow). It would seem possible that in suitable environment on another planet, self-replicating molecules could be based on silicon instead of carbon. That said, I'd assume silicon based life to have a lot lower probability because carbon is a lot more abundant element than silicon so there's a lot more changes for "life" to randomly build self-replicating molecule sequence with carbon simply because there's more carbon where the first self-replicating molecule could appear by change. That said, if somebody can build really simple self-replicating silicon-based molecule, that would totally change things. I would expect minimum self-replicating molecule to have roughly same complexity regardless if it's carbon-based or silicon-based. Right now, we don't know any simple carbon-based or silicon-based molecule capable of self-replication.
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