Afterwards, Larmor in 1897 and Lorentz in 1899[A 7] derived equations in an algebraically equivalent form to those, which are used up to this day (however, Lorentz used an undetermined factor l in his transformation). In his paper Electromagnetic phenomena in a system moving with any velocity smaller than that of light (1904)[A 3] Lorentz attempted to create such a theory, according to which all forces between the molecules are affected by the Lorentz transformation (in which Lorentz set the factor l to unity) in the same manner as electrostatic forces. In other words, Lorentz attempted to create a theory in which the relative motion of earth and aether is (nearly or fully) undetectable.