18.404J/6.840J The Theory of Computation(Fall 2020, MIT OCW). Instructor: Prof. Michael Sipser. This course emphasizes computability and computational complexity theory. Topics include regular and context-free languages, decidable and undecidable problems, reducibility, recursive function theory, time and space measures on computation, completeness, hierarchy theorems, inherently complex problems, oracles, probabilistic computation, and interactive proof systems.
(from ocw.mit.edu)
Lecture 17 - Space Complexity, PSPACE, Savitch's Theorem
Quickly reviewed last lecture. Introduced space complexity. Defined SPACE (f(n)), NSPACE (f(n)), PSPACE, and NPSPACE. Proved TQBF ∈ PSPACE, LADDERDFA ∈ NSPACE(n), and LADDERDFA ∈ SPACE(n2).