Michał Horodecki is a physicist at the University of Gdańsk working in the field of quantum information theory, notable for his work on entanglement theory.
Together with Jonathan Oppenheim and Andreas Winter, he discovered quantum state-merging and used this primitive to show that quantum information could be negative. He also co-discovered the Peres-Horodecki criterion for testing whether a state is entangled, and used it to find bound entanglement together with his brother Paweł Horodecki and father Ryszard Horodecki. He co-discovered with Jonathan Oppenheim, Paweł Horodecki and Karol Horodecki that secret key can be drawn from some bound entangled states. Together with Fernando Brandao he proved that every one-dimensional quantum state with a finite correlation length obeys an area law for entanglement entropy.