[FRIAM] Friam Digest, Vol 190, Issue 1

[uǝlƃ ☣]

I can only try.  And the people who actually know what they're talking about can correct my mangle.

Adjacent possible means something like one point mutation away from where we are now.  Like, it would be possible I wouldn't be bald if I could just tweak this one gene.  Iteration is applying a function to the output of a previous application.  E.g. "+"... +·+ (or +²) means (x+y)+z so that (x+y) is the input to the 2nd application of +.  In this sense, 2 is adjacent to 1 and 3.  So, if we're "at" the universe where x=2, then we can move to the adjacent universe with x+1 (or x-1).

A cellular automaton does this, applies a function over and over again to whatever the last state was.  The idea of exploring the possibilities that are only one point mutation away from where we are is like a cellular automaton.  If we change reality by point mutations, then we can slowly chunk along from where we are now to some *other* universe that looks kinda like ours but different in whatever ways that iterative function produced.

To take your example, if "everyone has the same annual income" is a reality that we could achieve by making a tiny change to our current reality (like maybe passing a law), then that's an adjacent possiblity.  We could move from this reality to that reality by making that change.  Then we could move from that new reality to some other reality by making a similarly small change.  Etc.

If all these possible universes already exist, then the mutation from where we are to a different reality is like a lens focusing on only one part of the whole.  Movement to the next universe over is just moving the lens a tiny bit.

My question is are the people who care about this stuff thinking the lens grows or shrinks as it moves?

But there are many other questions, like where does the function that's being iterated come from?  What are the requirements for that function?  (E.g. for any non-trivial universe, it would be super complicated... Is it invertible?  Using "comonads" helps answer some of those.)  Is the space of possible universes being explored smooth? ... convex? (can't get there from here), etc.

On 4/1/19 2:50 PM, Nick Thompson wrote:
> Nothing spooks me so much as when people I know and respect are using words I know and respect in combinations that make no sense to me.  You have often taken mercy on me in the past.  Can you provide a rough, English major's guide to what you-guys are talking about? 

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☣ uǝlƃ