Time-Lock Puzzles in the Random Oracle Model (2011) (people.seas.harvard.edu)

I think the impact of advancements in computing could be mitigated by giving certain guarantees about the best-case and worst-case scenarios for computing advancements. For example, rather than saying "this will take 35 years to crack" you could say "this will decrypt in 20-45 years, depending on how much computing efficiency improves".