- qc / 0 41 01 04 v 1 2 0 O ct 2 00 4 CAUSAL SITES AS QUANTUM GEOMETRY

ar X iv : g r - qc / 0 41 01 04 v 2 2 8 Se p 20 05 CAUSAL SITES AS QUANTUM GEOMETRY

We propose a structure called a causal site to use as a setting for quantum geometry, replacing the underlying point set. The structure has an interesting categorical form, and a natural " tangent 2-bundle, " analogous to the tangent bundle of a smooth manifold. Examples with reasonable finiteness conditions have an intrinsic geometry, which can approximate classical solutions to general relati...

ar X iv : h ep - l at / 0 01 00 50 v 1 2 7 O ct 2 00 0 Geometry of 4 d Simplicial Quantum Gravity with a U ( 1 ) Gauge Field ∗

The geometry of 4D simplicial quantum gravity with a U(1) gauge field is studied numerically. The phase diagram shows a continuous transition when gravity is coupled with a U(1) gauge field. At the critical point measurements of the curvature distribution of S 4 space shows an inflated geometry with homogeneous and symmetric nature. Also, by choosing a 4-simplex and fixing the scalar curvature ...

ar X iv : g r - qc / 0 51 01 27 v 1 3 1 O ct 2 00 5 Imprints of Spacetime Topology in the Hawking - Unruh Effect

X iv : g r - qc / 0 11 01 09 v 1 2 4 O ct 2 00 1 Acceleration - induced nonlocality : kinetic memory versus dynamic memory

The characteristics of the memory of accelerated motion in Min-kowski spacetime are discussed within the framework of the nonlocal theory of accelerated observers. Two types of memory are distinguished: kinetic and dynamic. We show that only kinetic memory is acceptable, since dynamic memory leads to divergences for nonuniform accelerated motion.

ar X iv : g r - qc / 0 61 01 42 v 1 2 7 O ct 2 00 6 Is quantum mechanics based on an invariance principle ?

Non-relativistic quantum mechanics for a free particle is shown to emerge from classical mechanics through the requirement of an invariance principle under transformations that preserve the Heisenberg position-momentum inequality. These transformations acting on the position and momentum uncertainties are induced by isotropic space dilatations. This invariance imposes a change in the laws of cl...