The General Linear group $GL(n, R)$ #
THIS FILE IS SYNCHRONIZED WITH MATHLIB4. Any changes to this file require a corresponding PR to mathlib4.
This file defines the elements of the General Linear group general_linear_group n R
,
consisting of all invertible n
by n
R
-matrices.
Main definitions #
matrix.general_linear_group
is the type of matrices over R which are units in the matrix ring.matrix.GL_pos
gives the subgroup of matrices with positive determinant (over a linear ordered ring).
Tags #
matrix group, group, matrix inverse
GL n R
is the group of n
by n
R
-matrices with unit determinant.
Defined as a subtype of matrices
The determinant of a unit matrix is itself a unit.
The GL n R
and general_linear_group R n
groups are multiplicatively equivalent
Given a matrix with invertible determinant we get an element of GL n R
Equations
Given a matrix with unit determinant we get an element of GL n R
Equations
Given a matrix with non-zero determinant over a field, we get an element of GL n K
An element of the matrix general linear group on (n) [fintype n]
can be considered as an
element of the endomorphism general linear group on n → R
.
This is the subgroup of nxn
matrices with entries over a
linear ordered ring and positive determinant.
Equations
Instances for ↥matrix.GL_pos
- matrix.GL_pos.has_neg
- matrix.GL_pos.has_distrib_neg
- matrix.special_linear_group.matrix.GL_pos.has_coe
- upper_half_plane.mul_action
- upper_half_plane.matrix.GL_pos.has_coe
- upper_half_plane.SL_on_GL_pos
- upper_half_plane.SL_to_GL_tower
- upper_half_plane.subgroup_GL_pos
- upper_half_plane.subgroup_on_GL_pos
- modular_form.complex.slash_action
Formal operation of negation on general linear group on even cardinality n
given by negating
each element.
Equations
- matrix.GL_pos.has_neg = {neg := λ (g : ↥(matrix.GL_pos n R)), ⟨-↑g, _⟩}
Equations
- matrix.GL_pos.has_distrib_neg = function.injective.has_distrib_neg coe matrix.GL_pos.has_distrib_neg._proof_1 matrix.GL_pos.has_distrib_neg._proof_2 matrix.GL_pos.has_distrib_neg._proof_3
special_linear_group n R
embeds into GL_pos n R
Equations
- matrix.special_linear_group.to_GL_pos = {to_fun := λ (A : matrix.special_linear_group n R), ⟨↑A, _⟩, map_one' := _, map_mul' := _}
Coercing a special_linear_group
via GL_pos
and GL
is the same as coercing striaght to a
matrix.
The matrix [a, -b; b, a] (inspired by multiplication by a complex number); it is an element of
$GL_2(R)$ if a ^ 2 + b ^ 2
is nonzero.
Equations
- matrix.plane_conformal_matrix a b hab = matrix.general_linear_group.mk_of_det_ne_zero (⇑matrix.of ![![a, -b], ![b, a]]) _
This instance is here for convenience, but is not the simp-normal form.