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Comments 161 to 180 out of 9050 in reverse chronological order.

\begin{equation*} \DeclareMathOperator\Coim{Coim} \DeclareMathOperator\Coker{Coker} \DeclareMathOperator\Ext{Ext} \DeclareMathOperator\Hom{Hom} \DeclareMathOperator\Im{Im} \DeclareMathOperator\Ker{Ker} \DeclareMathOperator\Mor{Mor} \DeclareMathOperator\Ob{Ob} \DeclareMathOperator\Sh{Sh} \DeclareMathOperator\SheafExt{\mathcal{E}\mathit{xt}} \DeclareMathOperator\SheafHom{\mathcal{H}\mathit{om}} \DeclareMathOperator\Spec{Spec} \newcommand\colim{\mathop{\mathrm{colim}}\nolimits} \newcommand\lim{\mathop{\mathrm{lim}}\nolimits} \newcommand\Qcoh{\mathit{Qcoh}} \newcommand\Sch{\mathit{Sch}} \newcommand\QCohstack{\mathcal{QC}\!\mathit{oh}} \newcommand\Cohstack{\mathcal{C}\!\mathit{oh}} \newcommand\Spacesstack{\mathcal{S}\!\mathit{paces}} \newcommand\Quotfunctor{\mathrm{Quot}} \newcommand\Hilbfunctor{\mathrm{Hilb}} \newcommand\Curvesstack{\mathcal{C}\!\mathit{urves}} \newcommand\Polarizedstack{\mathcal{P}\!\mathit{olarized}} \newcommand\Complexesstack{\mathcal{C}\!\mathit{omplexes}} \newcommand\Pic{\mathop{\mathrm{Pic}}\nolimits} \newcommand\Picardstack{\mathcal{P}\!\mathit{ic}} \newcommand\Picardfunctor{\mathrm{Pic}} \newcommand\Deformationcategory{\mathcal{D}\!\mathit{ef}} \end{equation*}

On left comment #9577 on Lemma 32.2.2 in Limits of Schemes

Between the first and second paragraph of the proof, for clarity, I suggested explaining that because is filtered, the morphisms for induce compatible morphisms for any .

On Chris left comment #9574 on Lemma 31.31.1 in Divisors

Perhaps I am a bit confused, in the local setting how does this show that the closed subscheme is ?

On Lucas Henrique left comment #9572 on Lemma 26.11.1 in Schemes

There's a slight hypothesis missing: any nonempty irreducible closed subset. Otherwise, the proof fails when it claims that is nonempty for at least one .

On Kevin Buzzard left comment #9571 on Lemma 11.6.2 in Brauer groups

Re comment 9206: you have now removed the word "central" from the statement of 074R and now the lemma is incorrect, as was pointed out in comment 4168 in 2019.

On Liam Nutley left comment #9570 on Section 4.19 in Categories

Typo at "An diagram M over I"

On Branislav Sobot left comment #9569 on Exercise 111.2.4 in Exercises

You probably meant "The set on the left hand side"

On Zhenhua Wu left comment #9568 on Section 9.15 in Fields

Nevermind, I found that the proof in that link was false.

On Branislav Sobot left comment #9567 on Section 110.27 in Examples

In the second paragraph, it should be "We claim there is no quasi-compact open " and "dense in ". In the third paragraph, it whould be "lying over the specialization ".

On Erhard Neher left comment #9566 on Lemma 34.7.11 in Topologies on Schemes

The statement of Lemma 021V could be more precise: the proof of the lemma shows that the functor is special cocontinuous, not only cocontinuous. The same remark applies to Lemma 0DBP for the ph topology

On Zhenhua Wu left comment #9565 on Section 9.15 in Fields

The link didn't appear as expected, so here it is: https://math.stackexchange.com/questions/4959185/if-e-sep-f-is-normal-then-e-f-is-normal-or-give-a-counter-example

On Zhenhua Wu left comment #9564 on Section 9.15 in Fields

For tag 0EXK, the reverse is also true, which is kind of counter-intuitive. So that lemma can be written in the form of if and only if. For a proof, see \ref{https://math.stackexchange.com/questions/4959185/if-e-sep-f-is-normal-then-e-f-is-normal-or-give-a-counter-example}.

On left comment #9563 on Lemma 59.96.5 in Étale Cohomology

The first sentence needs to state that the map from the section on coh of sites is from right to left. Pointed out by Felix Baril Boudreau.

On Branislav Sobot left comment #9559 on Lemma 31.31.4 in Divisors

In the equality there a union missing on the right-hand-side

On Luming Zhao left comment #9558 on Example 6.11.4 in Sheaves on Spaces

a small typo in the last sentence: "an element of (instead of if) is the same thing as ..." ?

On Branislav Sobot left comment #9557 on Lemma 31.15.12 in Divisors

Maybe number from should have other notation, since is also the number of associated points

On Branislav Sobot left comment #9556 on Lemma 31.15.8 in Divisors

Also, for the proof of the final statement, what happens with the irreducible components of which have codimension zero in ? For instance, what if is irreducible and , how do you find ?

On Branislav Sobot left comment #9555 on Lemma 31.15.8 in Divisors

Are you assuming in the statement that there are finitely many divisors ? If so, I suggest you add it. If not, then I don't understand what would the sum of these divisors be since we only defined finite sums of (effective Cartier) divisors. It also doesn't hurt to add to the statement that are nonnegative integers.

On Tony Scholl left comment #9554 on Lemma 20.4.3 in Cohomology of Sheaves

Shouldn't that be in the first construction, so as to be consistent with the preimage of being the original torsor ? (Also in 03AJ)

On Olivier Benoist left comment #9553 on Lemma 59.52.4 in Étale Cohomology

typo: K should be the pullback of K_0 (and not K) to X

On Erik left comment #9552 on Example 29.38.3 in Morphisms of Schemes

It should say relatively very ample instead of very ample in the sentence "In this case is a very ample invertible sheaf on ".


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