Effects of the quantisation ambiguities on the Big Bounce dynamics

Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

RevTeX4, 28 pages, 11 figs; rev.2 new section on exact solutions; (v3) published version

Scientific paper

10.1007/s10714-008-0689-2

In this paper we investigate dynamics of the modified loop quantum cosmology models using dynamical systems methods. Modifications considered come from the choice of the different field strength operator $\hat{F}$ and result in different forms of the effective Hamiltonian. Such an ambiguity of the choice of this expression from some class of functions is allowed in the framework of loop quantisation. Our main goal is to show how such modifications can influence the bouncing universe scenario in the loop quantum cosmology. In effective models considered we classify all evolutional paths for all admissible initial conditions. The dynamics is reduced to the form of a dynamical system of the Newtonian type on a 2-dimensional phase plane. These models are equivalent dynamically to the FRW models with the decaying effective cosmological term parametrised by the canonical variable $p$ (or by the scale factor $a$). We find that for the positive cosmological constant there is a class of oscillating models without the initial and final singularities. The new phenomenon is the appearance of curvature singularities for the finite values of the scale factor, but we find that for the positive cosmological constant these singularities can be avoided. For the positive cosmological constant the evolution begins at the asymptotic state in the past represented by the deSitter contracting (deS$_{-}$) spacetime or the static Einstein universe H=0 or $H=-\infty$ state and reaches the deSitter expanding state (deS$_{+}$), the state H=0 or $H=+\infty$ state. In the case of the negative cosmological constant we obtain the past and future asymptotic states as the Einstein static universes.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Effects of the quantisation ambiguities on the Big Bounce dynamics does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Effects of the quantisation ambiguities on the Big Bounce dynamics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effects of the quantisation ambiguities on the Big Bounce dynamics will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-506827

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.