GT4 - Inertial Forces, Optical Metrics and Particle Motion Properties |
Speaker_ |
Nester, James M |
Co-autors |
C.-M. Chen and J.-L. Liu |
Talk _ |
Quasilocal energy for cosmological models |
Abstract _ |
Our covariant Hamiltonian formalism gives a certain preferred Hamiltonian boundary term for quasilocal quantities which depends on the boundary conditions, plus a reference and displacement vector choice. With appropriate choices we found the quasilocal energy for the cosmological models. Homogeneous choices give vanishing energy for all regions of Bianchi class A models and positive energy for class B. Isotropic choices give energies proportional to the curvature parameter k: ie, vanishing for the flat case, positive for the closed model and negative(!) for the open model. Our values are consistent with the requirement that the energy vanishes for closed models. We have some conclusions regarding the best reference choice and two quasilocal desiderata: positivity and zero energy iff Minkowski space. |