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·11 lat temu·discuss
We have something between the two in HoTT - universes of types is stratified by homotopy levels, corresponding to how many dimensions of structure a type has. A space with only points is thus a 0-type, a space with at most 1 point is a -1-type, and a space with only one is a -2-type.

The catch is that univalence is inconsistent with LEM at h-levels greater than -1, but assuming it is perfectly consistent for -1 types, which can be thought of as the "at most true" propositions of classical logic.
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·11 lat temu·discuss
A lot of work was going into the cubical model, but IIRC they realized it was a dead end about a month and a half ago. Right now the most promising work looks to be formalizing the set theoretic model in NuPRL.
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·11 lat temu·discuss
Why would it do that? Univalence is unrelated to the halting problem.

What the univalence axiom says is that you can treat types you have proven isomorphic as equal.