Bifibrations #184
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Bifibrations #184
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plt-amy
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# Description This PR refactors (co)limits to be defined in terms of kan extensions. The main motivation for doing so is to make preservation of limits less annoying to deal with; as it currently stands we need to define special functions for mapping cones, which makes life much harder. ## Notes As noted on discord, representability does not work due to (annoying!) universe level issues. This PR is also based off #184; I'll rebase when the time comes. --------- Co-authored-by: Amélia Liao <me@amelia.how>
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Description
This PR defines bifibrations, and characterizes them as cartesian fibrations with left adjoints to base change.
Doing so cleanly requires a minor refactor of some properties of weak cartesian morphisms, along with some new
definitions:
This PR also adds the (start) of a natural isomorphism API; we should improve this in the future!
Notes
I couldn't come up with a better name for
push-out. Suggestions would be appreciated!