Towards Cosmological Dynamics from Loop Quantum Gravity
  We present a systematic study of the cosmological dynamics resulting from an
effective Hamiltonian, recently derived in loop quantum gravity using
Thiemann's regularization and earlier obtained in loop quantum cosmology (LQC)
by keeping the Lorentzian term explicit in the Hamiltonian constraint. We show
that quantum geometric effects result in higher than quadratic corrections in
energy density in comparison to LQC causing a non-singular bounce. Dynamics can
be described by the Hamilton's or the Friedmann-Raychaudhuri equations, but the
map between the two descriptions is not one-to-one. A careful analysis resolves
the tension on symmetric versus asymmetric bounce in this model, showing that
the bounce must be asymmetric and symmetric bounce is physically inconsistent,
in contrast to the standard LQC. In addition, the current observations only
allow a scenario where the pre-bounce branch is asymptotically de Sitter,
similar to a quantization of the Schwarzschild interior in LQC, and the
post-bounce branch yields the classical general relativity. For a quadratic
potential, we find that a slow-roll inflation generically happens after the
bounce, which is quite similar to what happens in LQC.
