Imagine shuffling a deck of cards where some of the cards are fading just because of the way they interact with the external environment as you shuffle them. Your job is to figure out the interplay between the shuffling, or “imposed randomness,” due to the way you shuffle your cards and how that relates to the fading as cards are exposed to the external environment.

That’s a rough analogy for what Matthew Duschenes and his Ph.D. advisers were doing in a paper that received an Editors’ Suggestion in the journal Physical Review A.

Duschenes is currently a postdoctoral researcher at the University of Guelph, and he earned his Ph.D. at Perimeter Institute and the University of Waterloo with the late Ray Laflamme, a Perimeter founding faculty member and founding director of the Institute for Quantum Computing, who died in 2025.