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Observations of the universe on very small and large scales have revealed a surprising economy in its basic laws and structure. In contrast, our theories have become increasingly complex and contrived, introducing many new particles, fields and even dimensions of space which are, as yet, unobserved. In this talk, I will outline a more economical and predictive program, aiming to solve cosmology’s main puzzles using only the Standard Model including neutrino masses and general relativity. Instead of postulating a period of inflation before the hot big bang, we extrapolate the observed simple universe all the way back to the singularity. Instead of adding new particles and forces, we assume a minimal modification of the Standard Model which improves the vacuum and preserves local scale symmetry. The symmetry ensures that the hot plasma filling the early universe is insensitive to the size of the universe as it shrinks to zero at the singularity. Mathematically, the singularity is replaced by a kind of mirror. The simplest-yet proposed dark matter candidate -- a stable, right handed neutrino – becomes viable, a possibility to be tested by galaxy surveys in the next few years. We calculate the gravitational entropy for realistic cosmologies, with radiation, matter, lambda and space curvature. We find that the entropy favours flat, homogeneous and isotropic universes like ours, with a small positive cosmological constant. We compute the primordial fluctuations which seeded the formation of galaxies and other structures in the universe, ab initio, in terms of Standard Model couplings. Remarkably, subject to two key theoretical assumptions, the amplitude and spectral tilt of these fluctuations agree with the observed values, with no free parameters. In principle, all features of the standard LambdaCDM model for cosmology are thereby explained in a highly predictive new framework which does not require inflation. I'll review forthcoming observational tests as well as remaining theoretical challenges.