Decoherence in Conformal Field Theory

TL;DR

This paper investigates decoherence in conformal field theories, linking it to heat capacity and central charge, analyzing entanglement decay, and exploring holographic duals in AdS/CFT, revealing effects on black hole horizons.

Contribution

It provides a detailed analysis of decoherence dynamics in CFTs, connecting quantum information measures to thermodynamic and holographic properties, and explores gravity duals of decoherence.

Findings

Decoherence time proportional to heat capacity.

Purity and negativity decay monotonically over time.

Decoherence rate proportional to central charge.

Abstract

Noise sources are ubiquitous in Nature and give rise to a description of quantum systems in terms of stochastic Hamiltonians. Decoherence dominates the noise-averaged dynamics and leads to dephasing and the decay of coherences in the eigenbasis of the fluctuating operator. For energy-diffusion processes stemming from fluctuations of the system Hamiltonian the characteristic decoherence time is shown to be proportional to the heat capacity. We analyze the decoherence dynamics of entangled CFTs and characterize the dynamics of the purity, and logarithmic negativity, that are shown to decay monotonically as a function of time. The converse is true for the quantum Renyi entropies. From the short-time asymptotics of the purity, the decoherence rate is identified and shown to be proportional to the central charge. The fixed point characterizing long times of evolution depends on the presence degeneracies in the energy spectrum. We show how information loss associated with decoherence can be attributed to its leakage to an auxiliary environment and discuss how gravity duals of decoherence dynamics in holographic CFTs looks like in AdS/CFT. We find that the inner horizon region of eternal AdS black hole is highly squeezed due to decoherence.