Lax Lean Archive

Proof of `The halting problems are undecidable` (2nd statement)

groundedproofs/Lax624099Proofs/Bridge.lean · lax-624099

What this proof establishes

thm✓Lax624099.HaltingUndecidable (2nd statement)

Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.

Read the Lean proof on GitHub

Description

The halting problem is RE-hard, and every RE-hard problem is undecidable.