Power objects!

I have added a short new chapter to Category Theory: Notes towards a gentle introduction. Just four-and-a-bit pages on “power objects” (i.e. objects which behave in a certain way as a powerset does in the category Set). This is really just an exercise in making the definition look tolerably well-motivated. I don’t want/need to run very far with the idea: I just want to have it in play for when I get round to first introducing the notion of a topos.

So the end of Part I of the Notes is in sight. I need to have a chapter expanding the current half-chapter on natural number objects, and another chapter expanding the current half-chapter on group objects. Then the Part will finish with a new chapter  introducing the notion of a topos (all the ingredients are in place) and looking ahead, motivating the transition to Part II. As all my predictions about how long things will take turn out to be useless, I won’t venture one. But whenever I do get to the end of Part I, the plan is to pause and work through it again making it as clear and unified in level and approach as I can, rather than rush on to Part II.

Post-covid chez Logic Matters continuous to be exceedingly tedious. Tests may come back negative, but the fatigue continues with only very slow improvement. Par for the course we are told. If we had the energy to be really annoyed, we’d be really annoyed …

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