OAI/Geometry/Arnold/Involution.lean
13 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.ArnoldCounterexample.Quadric.involutionLinearline 13Source documentation
The linear involution fixing the first coordinate.
def involutionLinear : CV ≃ₗ[ℂ] CV where …
Mentions: OAI.ArnoldCounterexample.CV
- lemma
OAI.ArnoldCounterexample.Quadric.involutionLinear_applyline 21 - lemma
OAI.ArnoldCounterexample.Quadric.involutionLinear_twiceline 24 - lemma
OAI.ArnoldCounterexample.Quadric.involutionLinear_quadricPolynomialline 27 - lemma
OAI.ArnoldCounterexample.Quadric.involutionLinear_normSquaredline 33 - lemma
OAI.ArnoldCounterexample.Quadric.involutionLinear_unitline 39 - lemma
OAI.ArnoldCounterexample.Quadric.linearEquiv_ne_zeroline 45Source documentation
An injective complex-linear symmetry of the cone acts on the actual projective quadric, not on a substitute abstract model.
lemma linearEquiv_ne_zero (D : CV ≃ₗ[ℂ] CV) {z : CV} (hz : z ≠ 0) : D z ≠ 0 := by …Mentions: OAI.ArnoldCounterexample.CV
- def
OAI.ArnoldCounterexample.Quadric.mapline 49 - lemma
OAI.ArnoldCounterexample.Quadric.map_mkline 57 - def
OAI.ArnoldCounterexample.Quadric.involutionline 65Source documentation
The Hamiltonian involution's underlying projective equivalence.
def involution : Q3 ≃ Q3 where …
Mentions: OAI.ArnoldCounterexample.Q3
- theorem
OAI.ArnoldCounterexample.Quadric.involution_sqline 83 - lemma
OAI.ArnoldCounterexample.Quadric.involution_projectline 86 - theorem
OAI.ArnoldCounterexample.Quadric.involution_fixed_project_iffline 91Source documentation
The +1 eigenline is not on the quadric. All projectively fixed lines therefore lie in precisely the hyperplane z0=0.
theorem involution_fixed_project_iff (z : UnitQuadric) : involution (project z) = project z ↔ (z : CV) 0 = 0 := by …Mentions: OAI.ArnoldCounterexample.UnitQuadric, OAI.ArnoldCounterexample.Quadric.involution, OAI.ArnoldCounterexample.project, OAI.ArnoldCounterexample.CV