Granger, LéoDinis Vizcaíno, Luis IgnacioHorowitz, Jordan M.Rodríguez Parrondo, Juan Manuel2023-06-172023-06-172016-090295-507510.1209/0295-5075/115/50007https://hdl.handle.net/20.500.14352/17693© EPLA, 2016. This work has been supported by grants ENFASIS (FIS2011-22644) and TerMic (FIS2014-52486-R) from the Spanish Government. JMH is supported by the Gordon and Betty Moore Foundation through Grant GBMF4343.We present a feedback protocol that is able to confine a system to a single microstate without heat dissipation. The protocol adjusts the Hamiltonian of the system in such a way that the Bayesian posterior distribution after measurement is in equilibrium. As a result, the whole process satisfies feedback reversibility - the process is indistinguishable from its time reversal- and assures the lowest possible dissipation for confinement. In spite of the whole process being reversible it can surprisingly be implemented in finite time. We illustrate the idea with a Brownian particle in a harmonic trap with increasing stiffness and present a general theory of reversible feedback confinement for systems with discrete states. editor's choice Copyright (C) EPLA, 2016.engjournal articlehttp://dx.doi.org/10.1209/0295-5075/115/50007http://iopscience.iop.org/https://arxiv.org/abs/1609.06461open access539.1ThermodynamicsInformationPrincipleFísica nuclear2207 Física Atómica y Nuclear