 The new symmetry of 'inversion' is given by the 3-tensor formula_11 This symmetry becomes Poincaré symmetry if we set formula_12 When formula_13 the second condition requires that formula_3 is an orthogonal matrix.This transformation is 1-1 meaning that each point is mapped to a unique point only if we theoretically include the points at infinity.The invariants for this symmetry in 4 dimensions is unknown however it is known that the invariant requires a minimum of 4 space-time points.