Some Meet-in-the-Middle Circuit Lower Bounds
نویسندگان
چکیده
We observe that a combination of known top-down and bottom-up lower bound techniques of circuit complexity may yield new circuit lower bounds. An important example is this: Razborov and Wigderson showed that a certain function f in ACC cannot be computed by polynomial size circuits consisting of two layers of MAJORITY gates at the top and a layer of AND gates at the bottom. We observe that a simple combination of their result with the H̊astad switching lemma yields the following seemingly much stronger result: The same function f cannot be computed by polynomial size circuits consisting of two layers of MAJORITY gates at the top and an arbitrary AC circuit feeding the MAJORITY gates.
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