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We derive the Wheeler-de Witt equation for the scalar field of mass m > 0 in a Bianchi-type I universe. We argue that classical trajectories become possible at h2 ⩽ αtp-2, h being the mean Hubble value and tp the Planck time. We feel justified to set the numerical constant α ≈︁ 1. We discuss this condition in geometrically invariant quantities and compare it with ⩽tp-4. The proposed quantum boundary of classical trajectories represents a 3-dimensional sphere in the 4-space of the dynamical system. Equipartition of the initial energy over field (m < mp) and shear variables at the quantum boundary will cause inflation with a probability p of the order p = 1 - m/mp thus, p = 1 - 10-4 for m taken from GUT. In the course of the inflationary stage the initially arbitrarily large shear-anisotropy exponentially decays. 相似文献
2.
Gangabrata Mukherjee 《Journal of Astrophysics and Astronomy》1986,7(4):259-273
We present the condition of vanishing shear in a spatially homogeneous spacetime in terms of the Ricci rotation co-efficients
corresponding to an orthonormal tetrad (ν
α.
A
η
α) (whereν
α is the unit vector along the time axis and
A
η
α are the three independent reciprocal group vectors). Assuming that the velocity vector can be expanded in the direction ofν
α and any one of the
A
η
α’s it is shown that shear-free motion is possible only in case of some special Bianchi types, and these cases are studied
assuming the velocity vector to be geodetic and that there may be a nonvanishing heat flux term. 相似文献
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