Kerodon

$\Newextarrow{\xRightarrow}{5,5}{0x21D2}$ $\newcommand\empty{}$
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$

Comments 1 to 20 out of 2623 in reverse chronological order.


On Weilong ZHAO left comment #2630 on Exercise 4.8.4.4 in The Homotopy Theory of $\infty $-Categories

It seems that the order constructed here lacks reflexivity hence is not a partial order. Thus is not a -category (Proposition 057U).


On Weilong ZHAO left comment #2629 on Proposition 4.8.2.19 in The Homotopy Theory of $\infty $-Categories

Little typo: In (2) it seems that should be corrected as .

Moreover, in the proof of implication , in my understanding the right oblique map is bijective because of 052G. Maybe it's better to attach such a reference here and assume that our is -coskeletal as the reduction made at the first paragraph, so that 052G (2) can be applied directly.


On Weilong ZHAO left comment #2628 on Theorem 5.4.9.2 in Fibrations of $\infty $-Categories

Little typos: 1. In the webpage, the brackets in seem not to be depicted as expectation (at least for me). 2. In the diagram of (a), it seems that one shouldn't take core at the left corner. 3. "... is an -simplex of...", it seems that should be corrected as . 4. In the definition of , the target is a simplicial set hence it should be corrected as . 5. The enumerations , , in the definition of aren't compiled well on the webpage (at least for me).

Moreover, in (02S0) and in the definition of , is the abbreviation for intended or just a typo?


On Weilong ZHAO left comment #2627 on Proposition 3.5.4.18 in Kan Complexes

Little typo: "(under the bijection provided by the the lower horizontal map)", a double "the" here.


On Weilong ZHAO left comment #2626 on Proposition 3.5.6.12 in Kan Complexes

In the proof, since one has lifted to a simplicial map , should be corrected as ?


On Weilong ZHAO left comment #2625 on Remark 3.1.2.8 in Kan Complexes

It seems that one can establish a stronger result: if is a Kan fibration of simplicial sets such that is surjective, then is a surjective simplicial map. In fact, for any vertex and vertex , if there exists an edge or in , one can lift it to an edge or in ; on the other hand, if and belong to the same component of , one can select a zig-zag diagram of edges in connecting them, which can be lifted inductively to a zig-zag diagram in connecting and a vertex of .


On Weilong ZHAO left comment #2624 on Proposition 3.5.5.12 in Kan Complexes

In the proof, "...we see that the degenerate -simplex coincides with on the horn ...", should be corrected as ? Otherwise we have directly without invoking the assumption is an -groupoid.


On Weilong ZHAO left comment #2623 on Example 9.1.1.7 in Large $\infty $-Categories

Little typo: A double "is" here.


On Weilong ZHAO left comment #2622 on Variant 5.5.5.9 in Fibrations of $\infty $-Categories

Here is the choice of terminology "-category of essentially -small -categories" intended or just a typo (with additional adjustive "essentially")?


On Weilong ZHAO left comment #2621 on Proposition 5.4.5.14 in Fibrations of $\infty $-Categories

Little typo: In the proof it seems that "" should be "", or "" by denoting .


On Weilong ZHAO left comment #2620 on Corollary 5.4.4.2 in Fibrations of $\infty $-Categories

Little typo: In the first sentence of the second paragraph of the proof, it seems that should be .


On Weilong ZHAO left comment #2619 on Proposition 5.4.3.8 in Fibrations of $\infty $-Categories

Little typo: it seems that in the expression of (c), should be .


On Weilong ZHAO left comment #2618 on Example 5.6.2.20 in Fibrations of $\infty $-Categories

Here it seems that to obtain one makes use of some functoriality of category of elements construction and sadly I failed to find a related discussion in the text. When we have a general natural transformation in , a possible way to introduce the associated simplicial map over is to apply Lemma 00B1 on and . However, since here is not assumed to be an -category, we lack the cocartesian hypothesis in Lemma 00B1 so that this kind of method doesn't work...


On Weilong ZHAO left comment #2617 on Example 7.3.9.5 in Limits and Colimits

It seems that the content of this Example coincides with that of Corollary 02XX ('s dualilty).


On Weilong ZHAO left comment #2616 on Proposition 7.3.9.1 in Limits and Colimits

Little typo: Here it seems that "" is a morphism in , not .


On Weilong ZHAO left comment #2615 on Proposition 7.3.8.23 in Limits and Colimits

Little typo: In the proof, it seems that "" should be corrected as ""; the same error also appears in the subsequent sentence.


On Kerodon left comment #2614 on Proposition 7.3.8.15 in Limits and Colimits

Yep. Thanks!


On Weilong ZHAO left comment #2613 on Proposition 7.3.8.15 in Limits and Colimits

Little typo: In diagram 0317, it seems that right bottom term should be corrected as .


On Kerodon left comment #2612 on Proposition 7.3.8.11 in Limits and Colimits

Yep. Thanks!


On Kerodon left comment #2611 on Proposition 7.3.8.8 in Limits and Colimits

Yep. Thanks!