Ryan Williams recently published a draft proving new lower bounds for ACC circuits. ACC (often known as ACC0) is the class of constant depth circuits with unbounded fan-in gates, where the usual AND/OR/NOT gates are supplemented by MODm gates for some constant m.
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4 April 2011
9 November 2010
New ACC circuit lower bounds
28 August 2010
deterministic 3SAT in O*(1.334^n) time
Robin Moser and Dominik Scheder have put an end to the stream of slight improvements in derandomizing Schöning’s randomized k-SAT algorithm from 1999. (more…)
27 August 2010
InfiniteStack / TheoryOverflow / CSTheory public beta
The initial batch of questions and answers at the Theoretical Computer Science Q&A forum seems promising. I encourage theoretical computer scientists to take a look, and to consider contributing.
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15 August 2010
A simple reduction
Recent online discussion about computational complexity included the notion that the structure of solutions of SAT might be useful in proving separation results. I want to point out a further obstacle to this idea. (more…)
13 August 2010
P not equal to NP (P ≠ NP) consequences
During the discussion about Vinay Deolalikar’s manuscript, many people commented about the consequences that would follow if we knew that P ≠ NP. I’d like to discuss these consequences in a little more detail.
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Constraints 
Beware normal hypergraph landmine
Tags: papers
In a classic 1972 paper László Lovász proved the (little) Perfect Graph Theorem, that the complement of every perfect graph is perfect. Another theorem from this paper links normal hypergraphs and perfect graphs. Perhaps this discussion will help someone avoid unnecessary grey hairs.
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