Unbounded entanglement can be needed to achieve the optimal success probability
Quantum entanglement is known to provide a strong advantage in many two-party distributed tasks. We investigate the question of how much entanglement is needed to reach optimal performance. For the first time we show that there exists a purely classical scenario for which no finite amount of entanglement suffices. To this end we introduce a simple two-party nonlocal game H, inspired by a paradox of Lucien Hardy. In our game each player has only two possible questions and can provide answers in a countable set. We exhibit a sequence of strategies which use entangled states in increasing dimension d and succeed with probability 1-O(d-c) for some c ≥ 0.13. On the other hand, we show that any strategy using an entangled state of local dimension d has success probability at most 1 - Ω(d-2). In addition, we show that any strategy restricted to producing answers in a set of cardinality at most d has success probability at most 1 - Ω(d-2). © 2014 Springer-Verlag.
2-s2.0-84904209519
Centre for Quantum Technologies
University of California, Berkeley
2014
978-3-662-43947-0
978-3-662-43948-7
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics); 8572 LNCS
1611-3349
0302-9743
PART 1
835
846
REVIEWED
OTHER
| Event name | Event acronym | Event place | Event date |
ICALP 2014 | Denmark | 2014-07-08 - 2014-07-11 | |