Håstad’s switching lemma

E120579

Håstad’s switching lemma is a fundamental result in computational complexity theory that provides powerful bounds on the simplification of Boolean formulas under random restrictions, with major applications in circuit lower bounds.

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Statements (42)

Predicate Object
instanceOf mathematical theorem ⓘ
result in computational complexity theory ⓘ
appearsIn Johan Håstad’s work on almost optimal lower bounds for small-depth circuits ⓘ
appliesTo CNF formulas ⓘ
DNF formulas ⓘ
small-depth Boolean circuits ⓘ
assumption random restriction chosen independently for each variable ⓘ
characterizes simplification of Boolean formulas under random restrictions ⓘ
field circuit complexity ⓘ
computational complexity theory ⓘ
theoretical computer science ⓘ
implies that random restrictions often yield shallow decision trees ⓘ
importance central tool in modern circuit lower bound proofs ⓘ
foundational result in the theory of AC0 circuits ⓘ
influenced subsequent switching lemmas and refinements ⓘ
mainConcept Boolean formulas ⓘ
circuit lower bounds ⓘ
decision trees ⓘ
random restrictions ⓘ
namedAfter Johan Håstad ⓘ
provides probabilistic bounds on decision tree depth after restriction ⓘ
relatedTo Ajtai’s lower bounds for constant-depth circuits ⓘ
Fourier analysis of Boolean functions ⓘ
Furst–Saxe–Sipser lower bounds ⓘ
random restriction method ⓘ
relates width of CNF or DNF to resulting decision tree depth ⓘ
shows probability that restricted formula has large decision tree depth is exponentially small in depth bound ⓘ
random restrictions simplify small-width CNF and DNF formulas ⓘ
strengthenedBy Håstad’s multi-switching lemma ⓘ
multi-switching lemmas ⓘ
toolFor Håstad’s optimal lower bounds for small-depth circuits ⓘ
Razborov–Smolensky style arguments for AC0[⊕] ⓘ
typicalConclusion restricted formula has small-depth decision tree with high probability ⓘ
typicalDomain formulas of bounded width ⓘ
usedFor AC0 circuit lower bounds ⓘ
correlation bounds between AC0 circuits and parity ⓘ
hardness amplification arguments in circuit complexity ⓘ
hierarchy theorems for small-depth circuits ⓘ
proving lower bounds for constant-depth circuits ⓘ
pseudorandomness constructions for AC0 ⓘ
showing limitations of small-depth circuits computing majority ⓘ
showing limitations of small-depth circuits computing parity ⓘ

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Referenced by (3)

Full triples — surface form annotated when it differs from this entity's canonical label.

Johan Håstad → knownFor → Håstad’s switching lemma ⓘ
Håstad’s switching lemma → strengthenedBy → Håstad’s multi-switching lemma ⓘ
linked to: Håstad’s switching lemma
Almost optimal lower bounds for small depth circuits → relatedTo → Håstad switching lemma ⓘ
linked to: Håstad’s switching lemma