6 papers
Einstein's Equations and Equivalent Hyperbolic Dynamical Systems
Arlen Anderson, Yvonne Choquet-Bruhat, James W. York
We discuss several explicitly causal hyperbolic formulations of Einstein's dynamical 3+1 equations in a coherent way, emphasizing throughout the fundamental role of the ``slicing f…
Generalized Einstein theory with fundamental cosmological stress tensor
Arlen Anderson
Careful analysis of parametrized variational principles in mechanics and field theory leads to a generalization of Einstein theory that includes a cosmological stress tensor. This…
Clocks and Time
Arlen Anderson
A general definition of a clock is proposed, and the role of clocks in establishing temporal pre-conditions in quantum mechanical questions is critically discussed. The different s…
Evolving Constants of Motion
Arlen Anderson
A critical presentation of Rovelli's ``evolving constants of motion'' is given. Previous criticisms by Kuchař concerning the role of factor ordering and the non-existence of observ…
Thawing the Frozen Formalism: The Difference Between Observables and What We Observe
Arlen Anderson
In a parametrized and constrained Hamiltonian system, an observable is an operator which commutes with all (first-class) constraints, including the super-Hamiltonian. The problem o…
The Global Problem of Time
Arlen Anderson
Time does not obviously appear amongst the coordinates on the constrained phase space of general relativity in the Hamiltonian formulation. Recent work in finite-dimensional models…