§Covariant
energy conservation:
§Note:
phantom if r+P(r)<0
§Remarks:
1.If for a
given EoS function P=P(r) there
exists a rL such that P(rL) = - rL, then rL has the dynamical role of an effective cosmological constant.
2.A given
non-linear EoS P(r) may admit
more than one point rL. If these
points exist, they are fixed points of the energy conservation equation.