The quantized Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) model minimally
coupled to a free massless scalar field is studied and interpreted in the
Bohm-de Broglie framework. We analyze the quantum bohmian trajectories
corresponding to a certain class of gaussian packets, solutions of the
Wheeler-DeWitt equation. We show that these bohmian trajectories undergo an
accelerated expansion in the middle of its evolution due to the presence of
quantum cosmological effects in this period. It is shown that the
luminosity-redshift relation in the quantum cosmological model can be made
close to the corresponding relation coming from the classical model suplemented
by a cosmological constant, for z<1. In this way we have the posibility of
interpreting the present observations of high redshift supernovae as the
consequence of a quantum cosmological effect.Comment: Talk given at X Marcell Grossmann Meeting, Rio de Janeiro, 2003.
Added references and some minor typos correction