Haifa University - Dept. of CS Theory Seminar

Speaker : Oded Regev, Tel-Aviv University.

Title: "Unique Games with Entangled Provers are Easy ".

Date: Thursday, June 12.

Place: Haifa U. Education Building, room 566.

Time: 12:15 - 13:30


We consider one-round games between a classical verifier and two provers who share entanglement. We show that
when the constraints enforced by the verifier are `unique' constraints (i.e., permutations), the value of the
game can be well approximated by a semidefinite program. Essentially the only algorithm known previously was
for the special case of binary answers, as follows from the work of Tsirelson in 1980. Among other things,
our result implies that the variant of the unique games conjecture where we allow the provers to share
entanglement is false. Our proof is based on a novel `quantum rounding technique', showing how to take a
solution to an SDP and transform it to a strategy for entangled provers.

NOTE: This talk requires absolutely no prior knowledge of quantum computation.

Joint work with Julia Kempe and Ben Toner.