Speaker
Description
We draw a picture of physical systems that allows us to recognize what
“time” is by requiring consistency with the way that time enters the
fundamental laws of Physics. Elements of the picture are two
non-interacting and yet entangled quantum systems, one of which acting
as a clock. The setting is based on the Page and Wootters mechanism,
with tools from large-N quantum approaches. Starting from an overall
quantum description, we first take the classical limit of the clock
only, and then of the clock and the evolving system altogether; we thus
derive the Schrödinger equation in the first case, and the Hamilton
equations of motion in the second.
Once the classical formalism is connected with a full quantum
description, ideal tools emerge for breaking through some of the
obstacles that make quantum gravity so difficult to process. In
particular, we suggest that our approach may provide a link between the
geodesic principle and the Schrödinger equation; furthermore, taking
into account a possible interaction between evolving system and clock.
Work in this direction is in progress and will be also reported,
particularly referring to the case of Schwartzschild black holes and
Hawking radiation.
