אירועים
אירועים והרצאות בפקולטה למדעי המחשב ע"ש הנרי ומרילין טאוב
ראול סנתנאם (אונ' אדינבורג)
יום רביעי, 11.05.2011, 12:30
חדר 337, בניין טאוב למדעי המחשב
Random restrictions are commonly used for proving complexity lower bounds,
eg. lower bounds
on constant-depth circuits (Ajtai, Furst-Saxe-Sipser, Yao,
Hastad) and lower bounds on formula
size (Subbotovskaya, Impagliazzo-Nisan,
Paterson-Zwick,
Hastad).
I will show how to use results on random restrictions to bound the running
time of
certain algorithms for Satisfiability which beat brute-force search.
Specifically I will present an
algorithm which runs in time 2^{n -
\Omega(n)} on Boolean formulae of linear size and an
algorithm which runs in
time 2^{n - n^{1/d+1}) on unbounded fan-in circuits of poly(n) size and
depth $d$.
I will also mention some more recent results motivated by our
work and make some general remarks on the connections between complexity
lower bound techniques and algorithmic analysis.