We aim at deepening our understanding of the notion of observer in physics by investigating the nature of observers at the overlap of quantum theory and relativity. We will employ recently developed techniques from quantum information, quantum metrology and their interplay with relativity, to develop a notion of clocks and spacetime probes which will provide ultimate bounds on possible measurements of physically accessible quantities. This will help us unveil the fundamental limitations imposed by the laws of Nature on observations. We will then exploit the channel capacity formalism to describe physical processes at the overlap of relativity and quantum physics as channels, which can transmit information between different regions of spacetime. Understanding the transmission rates and the bounds on the channel capacities will provide further indications on fundamental limitations imposed by Nature on human endeavours to measure and probe the Universe. Finally, we will discuss the philosophical implications of the notion of “observing the observer” within our relativistic and quantum framework. At last, we will attempt to understand if the limitations that Nature imposes on measurements are indeed fundamental or they cannot be distinguished from the human interaction with the world and are therefore  inextricably linked to human perception.

Coordinator: Prof. Ivette Fuentes (University of Vienna, Austria)

Start Date/end Date Progetto: August 2016/August 2018

Info at:



University of York, UK, Partner
Physics of the observer
Foundational Questions Institute (through Sylicon Valley Community Foundation)
Prof. Stefano Mancini