TY - GEN
T1 - Solution of the propeller conjecture in ℝ 3
AU - Heilman, Steven
AU - Jagannath, Aukosh
AU - Naor, Assaf
PY - 2012
Y1 - 2012
N2 - It is shown that every measurable partition {A 1,..., A k} of ℝ 3 satisfies (Equation Presented) Let {P 1,P 2,P 3} be the partition of ℝ 2 into 120° sectors centered at the origin. The bound (1) is sharp, with equality holding if A i=P i x ℝ for i ∈ {1,2,3} and A i = ∅ for i∈ {4,...,k}. This settles positively the 3-dimensional Propeller Conjecture of Khot and Naor (FOCS 2008). The proof of (1) reduces the problem to a finite set of numerical inequalities which are then verified with full rigor in a computer-assisted fashion. The main consequence (and motivation) of (1) is complexity-theoretic: the Unique Games hardness threshold of the Kernel Clustering problem with 4 x 4 centered and spherical hypothesis matrix equals 2π/3.
AB - It is shown that every measurable partition {A 1,..., A k} of ℝ 3 satisfies (Equation Presented) Let {P 1,P 2,P 3} be the partition of ℝ 2 into 120° sectors centered at the origin. The bound (1) is sharp, with equality holding if A i=P i x ℝ for i ∈ {1,2,3} and A i = ∅ for i∈ {4,...,k}. This settles positively the 3-dimensional Propeller Conjecture of Khot and Naor (FOCS 2008). The proof of (1) reduces the problem to a finite set of numerical inequalities which are then verified with full rigor in a computer-assisted fashion. The main consequence (and motivation) of (1) is complexity-theoretic: the Unique Games hardness threshold of the Kernel Clustering problem with 4 x 4 centered and spherical hypothesis matrix equals 2π/3.
KW - grothendieck inequalities
KW - kernel clustering
KW - semidefinite programming
KW - unique games hardness
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U2 - 10.1145/2213977.2214003
DO - 10.1145/2213977.2214003
M3 - Conference contribution
AN - SCOPUS:84862635715
SN - 9781450312455
T3 - Proceedings of the Annual ACM Symposium on Theory of Computing
SP - 269
EP - 276
BT - STOC '12 - Proceedings of the 2012 ACM Symposium on Theory of Computing
T2 - 44th Annual ACM Symposium on Theory of Computing, STOC '12
Y2 - 19 May 2012 through 22 May 2012
ER -