[Merged by Bors] - feat(AlgebraicGeometry): schemes are universally open over fields

[erdOne]

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[github-actions]

PR summary 99884c2730

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.RingTheory.Spectrum.Prime.Chevalley	1866	1867	+1 (+0.05%)

Import changes for all files

Files	Import difference
Mathlib.RingTheory.Spectrum.Prime.Chevalley	1

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Declarations diff

+ instance (priority := low) [IsIntegral Y] [Subsingleton Y] :
+ isOpenMap_comap_algebraMap_tensorProduct_of_field

You can run this locally as follows

## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>

The doc-module for scripts/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[joelriou]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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• ci (staging) / Build
• ci (staging) / Post-Build Step
• ci (staging) / Post-CI job