You see, now this doesn't make sense to me. When starting a block, I see it like a lottery. There are a finite number of possibilities to test. Granted it is a large number, but finite just the same. When you test one possibility and it fails, the number of possibilities available to the next test is one less. Until the block that you are working on is found, your odds against finding it would decrease. When the block is found, you are starting over in the sense that you have to create a new input to hash and go back to having that very large number of possibilities to work from. I'm told that this way of looking at it is wrong, and i accept that, it just doesn't make any sense to me.
That sounds very interesting and plausible to me. I hadn't considered it in those terms before.
However I think the reality is very different as I don't think anyone is keeping track of actual "progress" of the permutations that have been tried.
Edit: I believe time and date are part of the data being hashed. So being that the solution is time traveling, is there really a finite number of possible solutions?
Edit 2: Also the hash we are looking for isn't a static/specific one. We are just looking for one that meets or exceeds the current difficulty. So there could be an infinite number of solutions, or so it seems to me.
There's 2^256 possible hashes. That number is much bigger than a human mind can actually comprehend. There are a *LOT* of solutions. There's also nothing to prevent a duplicate hash (other than the statistical near-impossibility), since hashing involves changing a single bit to get a completely different result hash. There really is *nothing* that resembles progress when mining. Every hash is independent. This is why the rest of the network has no impact on your luck/variance (outside of influencing how quickly the next difficulty adjustment happens).
Oh, and work is updated every 30 seconds, meaning more transactions are included, different merkle root. This means a whole new set of hash data even if you repeated the same time, nonce, and extranonce as before for some reason.
