Unified Dark Energy and Dust Dark Matter Dual to Quadratic Purely Kinetic K-Essence

2016, February 20
E.I. Guendelman, E. Nissimov and S. Pacheva
European Physics Journal C76:90 (2016)
  s10052-016-3938-7
We consider a modified gravity plus single scalar-field model, where the
scalar Lagrangian couples symmetrically both to the standard Riemannian
volume-form (spacetime integration measure density) given by the
square-root of the determinant of the Riemannian metric, as well as to
another non-Riemannian volume-form in terms of an auxiliary maximal-rank
antisymmetric tensor gauge field. The pertinent scalar field dynamics
provides an exact unified description of both dark energy via dynamical
generation of a cosmological constant, and dark matter as a “dust” fluid
with geodesic flow as a result of a hidden Noether symmetry. The associated
quantum Wheeler-De Witt equation acquires the form of a Schroedinger-like
equation with an effective potential of inverted harmonic oscillator. The
quantum average value of the Friedmann-Lemaitre-Robinson-Walker scale
factor does not exhibit any singularities in its time evolution thus
implying absence of Big Bang creation and supporting the idea of "emerging"
universe.