Thermality isn't boring

You might think that thermal states aren't interesting from an information-theoretic or computational point of view, since they're maximally entropic. But the dynamics that leads quantum systems to thermalize in the first place can also be harnessed for useful quantum information tasks. In this talk, I'll review the eigenstate thermalization hypothesis (ETH), a foundational paradigm in quantum many-body physics which describes how thermal quantum systems look to local probes. I'll discuss two ways in which systems which obey ETH are amenable to QI techniques, based on recent work with Shozab Qasim at FU Berlin. First, I'll discuss the surprising effectiveness of Petz recovery on thermal states. Then I'll show how maximally chaotic thermal systems naturally host error-correcting codes, and how their code parameters are related to their thermodynamic properties. I'll comment on holographic and gravitational interpretations of these results.