Decoherence in the density matrix describing quantum three-geometries and the emergence of classical spacetime

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

78

Scientific paper

We construct the quantum gravitational density matrix ρ(gαβ,g'αβ) for compact three-geometries by integrating out a set of unobserved matter degrees of freedom from a solution to the Wheeler-DeWitt equation Ψ[gαβ,qk(matter)]. In the adiabatic approximation, ρ can be expressed as exp(-l2) where l2(gαβ,g'αβ) is a specific ``distance'' measure in the space of three-geometries. This measure depends on the volumes of the three-geometries and the eigenvalues of the Laplacian constructed from the three-metrics. The three-geometries which are ``close together'' (l2<<1) interfere quantum mechanically; those which are ``far apart'' (l2>>1) are suppressed exponentially and hence contribute decoherently to ρ. Such a suppression of ``off-diagonal'' elements in the density matrix signals classical behavior of the system. In particular, three-geometries which have the same intrinsic metric but differ in size contribute decoherently to the density matrix. This analysis provides a possible interpretation for the semiclassical limit of the wave function of the Universe.

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

Decoherence in the density matrix describing quantum three-geometries and the emergence of classical spacetime 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 Decoherence in the density matrix describing quantum three-geometries and the emergence of classical spacetime, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Decoherence in the density matrix describing quantum three-geometries and the emergence of classical spacetime will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1875344

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