Fundamental decoherence from quantum spacetime

Understanding whether quantum gravitational effects can lead to a fundamental decoherence, affecting all systems regardless of their environment, is a long standing open challenge. Here we provide a rigorous derivation of decoherence within a full-fledged model of quantum spacetime, encoded by noncommutativity at the Planck scale. Specifically, we obtain a generalized time evolution of quantum systems in which pure states can evolve into mixed states. This takes the form of a Lindblad-like time evolution for the density operator when the action of time translations generator is deformed by the effects of spacetime noncommutativity. The decoherence time for the evolution of a free particle is used to show that the Planck mass is the maximum allowed mass for elementary quantum systems. Bridging quantum mechanics and general relativity, two pillars of modern physics, lies at the forefront of scientific research. In this manuscript, the authors shed light on this problem by showing that the fundamental properties of spacetime at the Planck scale dictate quantum decoherence that transforms a pure quantum state into a mixed state.

Automated summary

In this paper, the authors provide a rigorous derivation of quantum decoherence within a quantum spacetime model, showing that pure states can evolve into mixed states due to the effects of spacetime noncommutativity. This study sheds light on the fundamental properties of spacetime at the Planck scale, bridging quantum mechanics and general relativity, and holds significant importance in scientific research.