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Does the Sheafsheaf $\mathcal{O}^*$ on a Complex Manifold Havecomplex manifold have an Acyclic Coveracyclic cover?

Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related questionthis related MathSE question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds: https://math.stackexchange.com/questions/1232364/does-a-complex-manifold-always-admit-an-acyclic-cover-for-the-sheaf-of-holomorph.

Therefore, the result would follow if the open sets and all intersections of this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.

Does the Sheaf $\mathcal{O}^*$ on a Complex Manifold Have an Acyclic Cover?

Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds: https://math.stackexchange.com/questions/1232364/does-a-complex-manifold-always-admit-an-acyclic-cover-for-the-sheaf-of-holomorph

Therefore, the result would follow if the open sets and all intersections of this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.

Does the sheaf $\mathcal{O}^*$ on a complex manifold have an acyclic cover?

Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related MathSE question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds.

Therefore, the result would follow if the open sets and all intersections of this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.

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Josh Lackman
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Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds: https://math.stackexchange.com/questions/1232364/does-a-complex-manifold-always-admit-an-acyclic-cover-for-the-sheaf-of-holomorph

Therefore, the result would follow if the open sets inand all intersections of this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.

Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds: https://math.stackexchange.com/questions/1232364/does-a-complex-manifold-always-admit-an-acyclic-cover-for-the-sheaf-of-holomorph

Therefore, the result would follow if the open sets in this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.

Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds: https://math.stackexchange.com/questions/1232364/does-a-complex-manifold-always-admit-an-acyclic-cover-for-the-sheaf-of-holomorph

Therefore, the result would follow if the open sets and all intersections of this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.

Source Link
Josh Lackman
  • 1.2k
  • 8
  • 14

Does the Sheaf $\mathcal{O}^*$ on a Complex Manifold Have an Acyclic Cover?

Let $X$ be a complex manifold and let $\mathcal{O}^*$ be the sheaf nonvanishing holomorphic functions on it. Does it have an acyclic cover? That is, a cover for which all open sets and all intersections are acyclic for this sheaf.

According to this related question, the sheaf $\mathcal{O}$ does since any complex manifold can be covered by Stein manifolds: https://math.stackexchange.com/questions/1232364/does-a-complex-manifold-always-admit-an-acyclic-cover-for-the-sheaf-of-holomorph

Therefore, the result would follow if the open sets in this cover by Stein manifolds could be taken to be contractible, due of the long exact sequence in cohomology associated to the short exact sequence

$0\to \mathbb{Z}\to \mathcal{O}\to \mathcal{O}^*\to 0\,.$

But I don't know if this can be done.