On P-selective Sets and EXP Hard Sets
نویسنده
چکیده
Let PSel be the class of all P-selective sets. We show that DTIME(2nk+a) 6 Pnk T(PSel) for all k; a > 0. It implies EXP 6 Pnc T(PSel) for all c > 0. This greatly improves Toda's result that EXP 6 Ptt(PSel) since Ptt(PSel) is equal to PO(logn) T(PSel). We construct an oracle A such that DTIME(2nk)A PAnk+1+a-T(PSel). We also show that the symmetric di erence of a EPm-hard set and a P-selective set is a EP2 T-hard. This generalizes a result by Rao [18] who showed the symmetric di erence of a EPm-hard set and a P-selective set is exponentially dense. 3 Symbols used in the paper: a; b; c; d; e; f; g; h; i; j; k; l;m;n; o; p; q; r; s; t; u; v; w; x; y; z A;B;C;D;E;F;G;H; I; J;K;L;M;N;O; P;Q;R; S; T; U; V;W;X; Y; Z [;\; ; ; ; ; ; ; ;9;8; ; ;4;k; [; ](; ); f:g; ();=); !; 6=;=; 2; ; ;; ; 6 ;8;^
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تاریخ انتشار 1997