Otherwise, all of that cryptocurrency's mining power could instantly abandon that cryptocurrency for the other thing if market flucations give it a higher ROI than PoW.
This doesn't really exist though, since you can heat a house with a mining rig. It's no less efficient than resistive heating.
Take primes. How do you know the person generated new primes and didnt just have a bunch saved up? With hashes you have to hash the current block which is unpredictable, and also means as time goes on it gets harder and harder to have a competing chain, because you dont just have to solve the current block but also be better for all the preceeding chains.
Additionally NP-complete problems are hard because the average complexity tends not to be super hard, which is a major sticking point in this application. So you have to somehow verify the person is solving a hard instance of the problem and not an easy instance.
Even factoring large semiprimes isn't inherently useful -- it's an interesting mathematical exercise, but isn't a goal unto itself.
examples would be: Multiple PoWers independently producing solutions and then verifying each other (although this is wasteful as work is being duplicated)
PoWers achieving increasing status levels when not cheating over time, incentivising long-term honest behaviour
> PoWers achieving increasing status levels when not cheating over time, incentivising long-term honest behaviour
We're talking millions of dollars here (if not more). In the real world people would easily spend years doing a long-con with that type of pay out. Why wouldn't they do so on the internet?
It won't work in the PoW scheme because there is presumably some cryptocurrency involved as a reward
For PoW you dont just need work, you need work that can be easily verified, easily scaled difficulty levels, and difficult to cheat with - all with no centralized trusted authority.
Even when SETI/F@H was worth only fake internet points they already had problems with people cheating. What happens when its worth real money?