mathlib

7e5eebd7 - feat(linear_algebra/clifford_algebra/equivs): There is a clifford algebra isomorphic to the dual numbers (#10730)

feat(linear_algebra/clifford_algebra/equivs): There is a clifford algebra isomorphic to the dual numbers (#10730) This adds a brief file on the dual numbers, and then shows that they are equivalent to the clifford algebra with `Q = (0 : quadratic_form R R)`.