Quantum Discord of Cosmic Inflation: Can we Show that CMB Anisotropies are of Quantum-Mechanical Origin?

Understand

We investigate the quantumness of primordial cosmological fluctuations and its detectability.

• The quantum discord of inflationary perturbations is calculated for an arbitrary splitting of the system, and shown to be very large on super-Hubble scales.
• This entails the presence of large quantum correlations, due to the entangled production of particles with opposite momentums during inflation.
• To determine how this is reflected at the observational level, we study whether quantum correlators can be reproduced by a non-discordant state, i.e.