From 4ae898dfe017403b6389f2057a0c6616190e0169 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Frederik=20Hangh=C3=B8j=20Iversen?= Date: Thu, 22 Mar 2018 14:51:43 +0100 Subject: [PATCH] Update backlog and changelog --- BACKLOG.md | 32 +++++++++++++++++++++++++------- CHANGELOG.md | 19 +++++++++++++++++++ 2 files changed, 44 insertions(+), 7 deletions(-) diff --git a/BACKLOG.md b/BACKLOG.md index c8fb54b..91d6b63 100644 --- a/BACKLOG.md +++ b/BACKLOG.md @@ -4,17 +4,37 @@ Backlog Prove postulates in `Cat.Wishlist`: * `ntypeCommulative : n ≤ m → HasLevel ⟨ n ⟩₋₂ A → HasLevel ⟨ m ⟩₋₂ A` +Prove that these two formulations of univalence are equivalent: + + ∀ A B → isEquiv (A ≡ B) (A ≅ B) (id-to-iso A B) + ∀ A → isContr (Σ[ X ∈ Object ] A ≅ X) + Prove univalence for the category of * the opposite category - * sets - This does not follow trivially from `Cubical.Univalence.univalence` because - objects are not `Set` but `hSet` * functors and natural transformations Prove: * `isProp (Product ...)` * `isProp (HasProducts ...)` +Ideas for future work +--------------------- + +It would be nice if my formulation of monads is not so "stand-alone" as it is at +the moment. + +We can built up the notion of monads and related concept in multiple ways as +demonstrated in the two equivalent formulations of monads (kleisli/monoidal): +There seems to be a category-theoretic approach and an approach more in the +style of functional programming as e.g. the related typeclasses in the +standard library of Haskell. + +It would be nice to build up this hierarchy in two ways: The +"category-theoretic" way and the "functional programming" way. + +Here is an overview of some of the concepts that need to be developed to acheive +this: + * Functor ✓ * Applicative Functor ✗ * Lax monoidal functor ✗ @@ -26,9 +46,7 @@ Prove: * Monoidal monad ✓ * Kleisli monad ✓ * Kleisli ≃ Monoidal ✓ - * Problem 2.3 in [voe] + * Problem 2.3 in [voe] ✓ * 1st contruction ~ monoidal ✓ * 2nd contruction ~ klesli ✓ - * 1st ≃ 2nd ✗ - I've managed to set this up so I should be able to reuse the proof that - Kleisli ≃ Monoidal, but I don't know why it doesn't typecheck. + * 1st ≃ 2nd ✓ diff --git a/CHANGELOG.md b/CHANGELOG.md index 625d640..42ab3e0 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -1,6 +1,25 @@ Changelog ========= +Version 1.4.1 +------------- +Defines a module to work with equivalence providing a way to go between +equivalences and quasi-inverses (in the parlance of HoTT). + +Finishes the proof that the category of homotopy-sets are univalent. + +Defines a custom "prelude" module that wraps the `cubical` library and provides +a few utilities. + +Reorders Category.isIdentity such that the left projection is left identity. + +Include some text for the half-time report. + +Renames IsProduct.isProduct to IsProduct.ump to avoid ambiguity in some +circumstances. + +[WIP]: Adds some stuff about propositionality for products. + Version 1.4.0 ------------- Adds documentation to a number of modules.