English

It costs nothing to teleport information into a black hole

High Energy Physics - Theory 2025-05-26 v2 General Relativity and Quantum Cosmology Quantum Physics

Abstract

It is often claimed that adding a qubit to a black hole requires energy ΔETHlog2\Delta E \geq T_H \log 2 so that the extra Bekenstein-Hawking entropy can accommodate the qubit. In this essay, we explain how the recently discovered phenomenon of black hole decoherence allows quantum information to be teleported into a black hole, with arbitrarily small energy cost. The generalized second law is not violated and there is no conflict with unitarity because the teleportation creates new entanglement, analogous to Hawking radiation, between the black hole interior and exterior. In accordance with Landauer's principle, a nonzero minimum energy cost only appears when there is a net erasure of information and noise from the exterior or, equivalently, when ``zerobits'' are sent into the black hole.

Keywords

Cite

@article{arxiv.2504.01058,
  title  = {It costs nothing to teleport information into a black hole},
  author = {Jonah Kudler-Flam and Geoff Penington},
  journal= {arXiv preprint arXiv:2504.01058},
  year   = {2025}
}

Comments

10 pages, 2 figures; v2: included explicit protocols demonstrating resource equalities. Awarded 2nd prize in Gravity Research Foundation 2025 Awards for Essays on Gravitation