PSPACE-hard

PSPACE-hard

In computational complexity theory, a decision problem "p" is said to be PSPACE-hard if, given any decision problem "q" in PSPACE, "q" can be reduced to "p" in polynomial time. PSPACE-hardness is distinguished from PSPACE-completeness by the fact that PSPACE-hardness does not require the problem to be in PSPACE. For example, the halting problem is PSPACE-hard, but not PSPACE-complete.


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