Recasting
Mermin's multi-player game into the framework of pseudo-telepathy
(pp538-550)
Gilles Brassard, Anne Broadbent, and
Alain Tapp
doi:
https://doi.org/10.26421/QIC5.7-2
Abstracts:
Entanglement is perhaps the most non-classical manifestation of quantum
\mbox{mechanics}. Among its many interesting applications to information
processing, it can be harnessed to \emph{reduce} the amount of
communication required to process a variety of distributed computational
tasks. Can it be used to eliminate communication
altogether? Even though it cannot serve to signal information between
remote parties, there are distributed tasks that can be performed
without any need for communication, provided the parties share prior
entanglement: this is the realm pseudo-telepathy.
One of the earliest uses of multi-party entanglement
was presented by Mermin in 1990. Here we recast his idea in terms of
pseudo-telepathy: we provide a new computer-scientist-friendly analysis
of this game. We prove an upper bound on the best possible classical
strategy for attempting to play this game, as well as a novel, matching
lower bound. This leads us to considerations on how well imperfect
quantum-mechanical apparatus must perform in order to exhibit a
behaviour that would be classically impossible to explain. Our results
include improved bounds that could help vanquish the infamous detection
loophole.
Key words:
entanglement |