Ryan Williams recently published a draft proving new lower bounds for ACC circuits. ACC (often known as ACC^{0}) is the class of constant depth circuits with unbounded fan-in gates, where the usual AND/OR/NOT gates are supplemented by MOD_{m} 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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## 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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