feat: immersed submanifolds - #26391
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Sadly, we cannot prove most nice things about them yet, as we don't have the inverse function theorem yet.
I'd merely like to ask for equality on the source of the inverse extChart
In finite dimensions, that certainly holds; need to think about inf-dim
The naive proof certainly fails (we get a coordinate change between the two charts in the middle, which can be anything, and need not be linear at all). Can we always "modify" a slice chart to match a modification downstairs? I presume no, but would need to think...
…f composition (coming next, after lunch)
…osition lemmas with diffeos.
…what I need is mostly in mathlib.
Need to assume interior points for some of the statements, and also n being at least 1. (If a map is not differential, its mfderiv certainly doesn't split.)
Otherwise, proving continuity of immersions at boundary points runs into an issue. This matches the definition in Roig-Domingues (and Lang seems to glance over that issue/doesn't consider manifolds with boundary anyway), so should be fine.
PR summary f2e9b91e31Import changes for modified filesNo significant changes to the import graph Import changes for all files
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| Current number | Change | Type |
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| 840 | 2 | erw |
Current commit cf367500fe
Reference commit f2e9b91e31
You can run this locally as
./scripts/technical-debt-metrics.sh pr_summary
- The
relativevalue is the weighted sum of the differences with weight given by the inverse of the current value of the statistic. - The
absolutevalue is therelativevalue divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).
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This PR/issue depends on: |
- my construction only makes sense if H and M are both non-empty - if both are empty, there is another construction - *if* we knew M has a charted space, we'd deduce that non-emptiness of M implies that of M. but we do not know yet... need to think!
…hought" This reverts commit 3ceab66.
8b8a4b4 to
696ac29
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This pull request has conflicts, please merge |
Still under construction
SliceModeltypeclass for models with corners for embedded submanifolds #26087Better version of #24549.