  The standard LambdaCDM model of cosmology is usually understood to arise from
demanding that the Friedmann-Lemaitre-Robertson-Walker (FLRW) metric satisfy
the General Relativity dynamics for spacetime metrics. The FLRW data-based
dominant parameter values, Omega_Lambda=0.73 and Omega_m=0.27 for the dark
energy and dark matter+matter, respectively, are then determined by fitting the
supernova red-shift data. However in the pressure-less flat-space case the
LambdaCDM model is most easily derived from Newtonian gravity, and which was
based on the special case of planetary motion in the solar system. Not
surprisingly when extended to galactic rotations and cosmology Newtonian
dynamics is found to be wanting, and the fix-up involves introducing dark
matter and dark energy, as shown herein. However a different theory of gravity
leads to a different account of galactic rotations and cosmology, and does not
require dark matter nor dark energy to fit the supernova data. It is shown that
fitting the LambdaCDM model to this new model, and so independently of the
actual supernova data, requires the LambdaCDM model parameters to be those
given above. Hence we conclude that dark energy and dark matter are no more
than mathematical artifacts to fix-up limitations of Newtonian gravity. Various
other data are also briefly reviewed to illustrate other successful tests of
this new theory of gravity.
