English
An analogous unit element exists in the tangent space for a complex Icc model with corners at Real coordinates.
Русский
Существует аналогичный единичный элемент в касательном пространстве для сложной модели Icc с углами.
LaTeX
$$$\text{One in } \mathrm{TangentSpace}(\text{modelWithCornersEuclideanHalfSpace } 1)\; z$$$
Lean4
/-- Unit vector in the tangent space to a segment, as the image of the unit vector in the real line
under the canonical projection. It is also mapped to the unit vector in the real line through
the canonical injection, see `mfderiv_subtype_coe_Icc_one`.
Note that one cannot abuse defeqs for this definition: this is *not* the same as the vector
`fun _ ↦ 1` in `EuclideanSpace ℝ (Fin 1)` through defeqs, as one of the charts of `Icc x y` is
orientation-reversing. -/
def oneTangentSpaceIcc :=
val_proj @wrapped✝.{}
