41 research outputs found
Generating function techniques for loop quantum cosmology
Loop quantum cosmology leads to a difference equation for the wave function
of a universe, which in general has solutions changing rapidly even when the
volume changes only slightly. For a semiclassical regime such small-scale
oscillations must be suppressed, by choosing the parameters of the solution
appropriately. For anisotropic models this is not possible to do numerically by
trial and error; instead, it is shown here for the Bianchi I LRS model how this
can be done analytically, using generating function techniques. Those
techniques can also be applied to more complicated models, and the results
gained allow conclusions about initial value problems for other systems.Comment: 22 pages, 5 figures; version to appear in CQ
Separable sequences in Bianchi I loop quantum cosmology
In this paper, we discuss the properties of one-parameter sequences that
arise when solving the Hamiltonian constraint in Bianchi I loop quantum
cosmology using a separation of variables method. In particular, we focus on
finding an expression for the sequence for all real values of the parameter,
and discuss the pre-classicality of this function. We find that the behavior of
these preclassical sequences imply time asymmetry on either side of the
classical singularity in Bianchi I cosmology.Comment: 5 pages, 3 figures, published versio
