  It has been shown earlier that Noether symmetry does not admit a form of F(R)
corresponding to an action in which F(R) is coupled to scalar-tensor action for
gravity or even for pure F(R) gravity taking anisotropic model into account.
Here, we prove that F(R) theory of gravity does not admit Noether symmetry even
if it is coupled to Tachyonic field and considering a gauge in addition. To
handle such a theory, a general conserved current has been constructed under a
condition which decouples higher order curvature part from the field part. This
condition in principle, solves for the scale factor, independently. Thus
cosmological evolution remains independent of the form of the chosen field,
whether it be a scalar or a tachyon.
