Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The classical action for a Bianchi VI_h model   An estimate for the classical action for a Bianchi VI_h homogeneous spatially
closed cosmology is presented as a function of b, a parameter of the model that
is proportional to the relative rotation of the average inertial frame and the
bulk of matter in the universe. It is assumed (through the equation of state)
that a relativistic early universe is followed by a matter-dominated late
universe. The action is used in a saddlepoint approximation to a semiclassical
estimate for the wave function in quantum cosmology to explain why our inertial
frame seems not to rotate relative to the stars. The saddlepoint is at b=0, as
would be expected. Application of the saddlepoint approximation leads to the
result that only those classical geometries whose action differs from the
saddlepoint value for the action by an amount less than Planck's constant
contribute significantly to the integration to give the present value of the
wave function. Using estimates for our universe implies that only those
classical geometries for which the present relative rotation rate of inertial
frames and matter are less than about 10^(-130) radians per year contribute
significantly to the integration. This is well below the limit set by
experiment. The result depends on the ratio of the Hubble distance to the
Planck length, but does not depend on the details of the theory of quantum
gravity.

16
The categories of this paper are: stat
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org