Institute for Astronomy and Astrophysics

The quantum clock: a critical discussion on (space-)time

Montag 8.06
Luciano Burderi (University of Cagliari)

Abstract:

We critically discuss the measure of very short
time intervals. By means of a Gedankenexperiment, we describe
an ideal clock based on the occurrence of completely random
events. We show that the minimum time interval dt that this
clock can measure scales as the inverse of its size dr.
This implies an uncertainty relation between space and time:
dr dt >= Gh/(2pi c^4)
where G, h, and c are the gravitational constant, the Planck
constant, and the speed of light, respectively.
We outline and briefly discuss the implications of this
uncertainty principle. Finally we will discuss an experiment,
based on a balloon-borne very large area detector, capable to
investigate (sub)millisecond structures in the prompt emission
of Gamma Ray Bursts. We show that energy-dependent time lags
in these phenomena could probe the granular structure of the
space-time fabric down to the Planck scale.