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CMP.11:1 - Problem frame

Use this when repeated attempts to accelerate a computation leave a question about what any algorithm could achieve under the available access. You can construct different admitted inputs that require different answers but remain indistinguishable before enough queries, comparisons, communication or stored information.

The gain is a lower bound tied to an explicit computational model, or a concrete change of access or requested answer that escapes that bound. This can stop fruitless optimization, reveal a needed index or observation, and separate an intrinsic restriction of the chosen model from a poor implementation.

The reader needs to follow the input family, allowed observations and the demanded answer. Counting, elementary probability or a mathematical adversary argument is used according to the branch. The adversary is a proof construction: it keeps several inputs consistent with what an algorithm has learned.

Use a known applicable bound directly when no new argument is needed. Timing one program establishes its performance, not a lower bound for every program. Undecidability through an effective reduction uses CMP.1; physical energy or transport limits use their physical formulation. The present method establishes computational information requirements under specified access.