The Issue of the Beginning in Quantum Gravity

Abstract

AbstractTreatises on Time, the Beginning and the End date back at least twenty-five centuries. Does the flow of time have an objective, universal meaning beyond human perception? Or, is it fundamentally only a convenient, and perhaps merely psychological, notion? Are its properties tied to the specifics of observers such as their location and state of motion? Did the physical universe have a finite beginning, or has it been evolving eternally? Leading thinkers across cultures meditated on these issues and arrived at definite but strikingly different answers. For example, in the sixth century B.C.E., Gautama Buddha taught that ‘a period of time’ is a purely conventional notion; time and space exist only in relation to our experience, and the universe is eternal. In the Christian thought, however, the universe had a finite beginning, and there was debate as to whether time represents ‘movement’ of bodies or whether it flows only in the soul. In the fourth century C.E., St. Augustine held that time itself started with the world.KeywordsQuantum GravityClassical TrajectoryLoop Quantum GravityQuantum GeometryLoop Quantum CosmologyThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.