Probability, unitarity, and realism in generally covariant quantum information

TL;DR

This paper discusses a covariant quantum information framework compatible with general relativity, emphasizing unitarity, realism, and new predictions related to the quantum Zeno effect.

Contribution

It introduces a covariant quantum information formalism that maintains unitarity and realism, resolving interpretational ambiguities of previous covariant quantum theories.

Findings

Agreement with standard quantum mechanics in the appropriate limit

Framework is fully unitary and realist

Predicts new phenomena related to the quantum Zeno effect

Abstract

The formalism of covariant quantum theory, introduced by Reisenberger and Rovelli, casts the description of quantum states and evolution into a framework compatable with the principles of general relativity. The leap to this covariant formalism, however, outstripped the standard interpretation used to connect quantum theory to experimental predictions, leaving the predictions of the RR theory ambiguous. Here we discuss in detail some implications of our recently proposed description of covariant quantum information (CQI), which addresses these problems. We show explicit agreement with standard quantum mechanics in the appropriate limit. In addition to compatability with general covariance, we show that our framework has other attractive and satisfying features -- it is fully unitary, realist, and self-contained. The full unitarity of the formalism in the presence of measurements allows us to invoke time-reversal symmetry to obtain new predictions closely related to the quantum Zeno effect.