Sciweavers

Share
ICALP
2003
Springer

A Direct Sum Theorem in Communication Complexity via Message Compression

11 years 12 months ago
A Direct Sum Theorem in Communication Complexity via Message Compression
We prove lower bounds for the direct sum problem for two-party bounded error randomised multipleround communication protocols. Our proofs use the notion of information cost of a protocol, as defined by Chakrabarti et al. [CSWY01] and refined further by Bar-Yossef et al. [BJKS02]. Our main technical result is a ‘compression’ theorem saying that, for any probabilitydistribution£ over the inputs, a ¤ -round private coin bounded error protocol for a function ¥ with information cost ¦ can be converted into a ¤ round deterministic protocol for ¥ with bounded distributionalerror and communication cost §©¨¤¦ . We prove this result using a substate theorem about relative entropy and a rejection sampling argument. Our direct sum result follows from this ‘compression’ result via elementary information theoretic arguments. We also consider the direct sum problem in quantum communication. Using a probabilisticargument, we show that messages cannot be compressed in this man...
Rahul Jain, Jaikumar Radhakrishnan, Pranab Sen
Added 06 Jul 2010
Updated 06 Jul 2010
Type Conference
Year 2003
Where ICALP
Authors Rahul Jain, Jaikumar Radhakrishnan, Pranab Sen
Comments (0)
books