31–40 of 146 posts
For most cryptocoins, you want a proof-of-work to be: (1) easy for a computer to verify, (2) hard for a computer to perform, (3) impossible to predict for a given 'block' and (4) decentralized and untrusted. If it's a novel scientific problem it won't be all of these. An interesting exception is prime numbers. Primecoin [1] has a useful proof-of-work: it finds Cunningham chains of primes. If you don't like the energy…
If mining an invalid chain is "useful" in some way, the security guarantee disappears.
How is it verified? I thought the problem with doing useful work instead of normal PoW was that producing and verifying are equally hard, while Bitcoin's PoW scheme is hard to produce but easy to verify (so other miners can easily see that you've actually found the hash without doing any computations themselves).
For most cryptocoins, you want a proof-of-work to be: (1) easy for a computer to verify, (2) hard for a computer to perform, (3) impossible to predict for a given 'block' and (4) decentralized and untrusted. If it's a novel scientific problem it won't be all of these. An interesting exception is prime numbers. Primecoin [1] has a useful proof-of-work: it finds Cunningham chains of primes. If you don't like the energy…
Folding can be verified easier than it can be produced.
This may be misunderstanding the function of PoW. Bitcoin PoW provides three things: selection, security, and incentive. The compute resource burn is an externality, although, it also ends up providing an important function, economic distribution. For PoW to work,it has to be hard to produce, easy to verify, and most importantly, attest to one and only one state of the blockchain. The last part is where this fails as…
Can you just hash a new solution to the puzzle with the new proposed block?
Earlier quoted context omitted.
Even if you have people doubling or tripling up the work on something useful, the end result is infinitely more useful than bruteforced hashes.
Don't forget that the usefulness of brute forced hashes is that it lets you have decentralized trust, so, you may be off by a factor of infinity.
It’s ultimately a quixotic goal. So compromising a bit on mathematical decentralized trustlessness to accomplish some of the other goals of cryptocurrency while addressing the massive waste is a valid goal IMHO.
Earlier quoted context omitted.
There's plenty of usefull work that we won't run out of. SAT solving is the prime candidate, because we have A LOT of NP hard problems in our day to day lives. Weather simulations are another one, drug research is another one. For the latter I'd argue that if we're at a point where we've erredicated all disease, we've also transcended as a society to a point where money has become obsolete.
This is besides the point, and the parent didn't quite explain it correctly. If there is no opportunity cost for mining, there is no penalty for mining an invalid chain therefore no security.
Earlier quoted context omitted.
Can you just hash a new solution to the puzzle with the new proposed block?
Solution has to depend on the proposed block, so that a solution is not reusable for the next block
Earlier quoted context omitted.
Folding can be verified easier than it can be produced.
There's no points for partial credit. It cannot be decentralized, untrusted and unpredictable. If anything other than an automaton produces the PoW inputs, it's at least centralized and we must trust that no one is cheating the PoW.
EDIT: Anyone using an online wallet is already compromising trustlessness. Heck, using common software packages that you didn’t personally inspect is also compromising trustlessness. But does this matter in practicality? Yes (such online wallets and even sometimes soft wallets have been compromised or have lost coins occasionally), but not enough to necessarily get rid of all of the utility of cryptocurrency.