Charts on regular zero sets of sections over Banach manifolds #
A source chart and the complemented-kernel implicit function theorem give coordinates on regular zeros of a bundle section. The charts are on the actual zero set. Their sources are restricted to the bundle trivialization's base set and the neighbourhood where the implicit coordinate map has invertible derivative. A surjective Fredholm derivative of constant index identifies each kernel with the same finite-dimensional model.
sectionZeroChartedSpace assembles this atlas. Smoothness of transitions and the inclusion are
proved in Section.Manifold. The source is modelled on a Banach space without boundary.
References #
- D. McDuff, D. Salamon, J-holomorphic Curves and Symplectic Topology, 2nd ed., Appendix A.3.
The construction uses Mathlib's complemented-kernel implicit function theorem and
OpenPartialHomeomorph.subtypeCoord.
The preferred chart at a regular Fredholm zero, in source-manifold coordinates. Its source is restricted to the bundle trivialization and the regular implicit-coordinate neighbourhood, and its kernel coordinates are identified with the index model.
Instances For
A preferred chart's source consists of zeros in the source-chart and bundle trivialization domains, whose coordinates belong to the regular implicit-function source.
The preferred chart reads source-chart displacement through the kernel projection.
The target is the implicit zero slice whose inverse stays in the regular neighbourhood, the source-chart target, and the bundle-trivialization domain.
On the target, the inverse preferred chart is the inverse ambient source chart applied to the inverse implicit coordinates on the zero slice.
The inverse chart remains in the ambient source-chart source, the bundle-trivialization base set, and the regular implicit-function neighbourhood.
A preferred chart is centred at its zero.
Every zero lies in the source of its preferred chart.
The origin belongs to the preferred chart target.
The inverse chart sends the origin to its zero.
The atlas of preferred implicit-function charts on the actual section zero set.
Instances For
The installed preferred charts are sectionZeroChartAt.
The installed atlas consists exactly of the preferred charts.