[Merged by Bors] - feat(Algebra/Lie): a Lie algebra is solvable iff it is solvable after faithfully flat base change

[jcommelin]

---

[github-actions]

PR summary 57c8589a72

Import changes exceeding 2%

%	File
+31.88%	Mathlib.Algebra.Lie.Nilpotent
+43.78%	Mathlib.Algebra.Lie.Solvable

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Algebra.Lie.Solvable	1126	1619	+493 (+43.78%)
Mathlib.Algebra.Lie.Nilpotent	1258	1659	+401 (+31.88%)

Import changes for all files

Files	Import difference
Mathlib.Algebra.Lie.Weights.RootSystem	328
Mathlib.Algebra.Lie.Weights.Killing	332
Mathlib.Algebra.Lie.Weights.Chain	353
7 files Mathlib.Algebra.Lie.Derivation.Killing Mathlib.Algebra.Lie.Killing Mathlib.Algebra.Lie.LieTheorem Mathlib.Algebra.Lie.TraceForm Mathlib.Algebra.Lie.Weights.Basic Mathlib.Algebra.Lie.Weights.Cartan Mathlib.Algebra.Lie.Weights.Linear	354
Mathlib.Algebra.Lie.CartanExists Mathlib.Algebra.Lie.Rank	357
4 files Mathlib.Algebra.Lie.CartanSubalgebra Mathlib.Algebra.Lie.EngelSubalgebra Mathlib.Algebra.Lie.Engel Mathlib.Algebra.Lie.Nilpotent	401
Mathlib.Algebra.Lie.Character Mathlib.Algebra.Lie.InvariantForm	418
3 files Mathlib.Algebra.Lie.Semisimple.Basic Mathlib.Algebra.Lie.Semisimple.Defs Mathlib.Algebra.Lie.Solvable	493

---

Declarations diff

+ derivedSeriesOfIdeal_baseChange
+ derivedSeries_baseChange
+ instance {A : Type*} [CommRing A] [Algebra R A] [IsSolvable L] : IsSolvable (A ⊗[R] L) := by
+ isSolvable_tensorProduct_iff
+ one_tmul_eq_zero_iff

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 script/declarations_diff.sh contains some details about this script.

---

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).

[ocfnash]

I like where this is heading :)

Thanks!

bors d+

[mathlib-bors]

✌️ jcommelin can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

[jcommelin]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• Build
• Lint style