blog:2025-07-02
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blog:2025-07-02 [2025/07/03 06:58] – created pzhou | blog:2025-07-02 [2025/07/03 09:00] (current) – pzhou | ||
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What is the so called inflation-deflation, | What is the so called inflation-deflation, | ||
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let me try to understand (3.1.4). We start life with a cube worth of categories, and functors lining the edges. We assume there is a biCartesian fibration, which means there exists (up to contractible choices) a unique lift of an edge if we fix the starting point, or the ending point. | let me try to understand (3.1.4). We start life with a cube worth of categories, and functors lining the edges. We assume there is a biCartesian fibration, which means there exists (up to contractible choices) a unique lift of an edge if we fix the starting point, or the ending point. | ||
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+ | We look at a square in the cube, and project the cube to the square. Say a 3-dim cube, so we are left with 1-dim interval in the fiber. We start with the fiber in the upper right corner. we start with the initial node in that fiber, run co-cartesian extension to the full fiber, then for each fiber position, we have a natural transformation. what's wrong with that? why we need to do deflation? ok, whatever. we still get [1]^{n-1}, in which one direction is in the diagonal base direction, and (n-2) is the fiber direction. And this cube is in the category of functors from this tip to that tip. | ||
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+ | the total fiber of (3.1.5) as the BC defect. Question, if we permute the ordering of the index, is it still the same thing? why the first two indices? | ||
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+ | If we want to use ' | ||
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+ | OK, maybe I want to say, there are two ways of doing restriction, | ||
blog/2025-07-02.txt · Last modified: 2025/07/03 09:00 by pzhou