MaiaVictor

You don't need to be sure the person *actually* mined that block in the right interval. I can mine the 12:20 block even 1 day later if you want to. But you can't mine the 1000th block, if the network has lived for only 2 hours. I.e., on the first 10 minutes, your node won't accept chains larger than 1 block. On the 20th minute, it accepts chains up to 2 blocks. On the 30th minute, it accepts chains up to 3 blocks. I.e., each node would define a maximum acceptable length as a function of its internal clock:

Fair enough, but what that gets you? Let's say you're mining the 38th block on top of your private 37th block that has a score of 1000. The current public 37th block has a score of 800. People are now mining the 38th block on top of it.

So, you're lonely mining on top of your 1000-score block, with your, say, 10 hashes per second. The rest of the network is mining on top of the 800-score block with its total of 1000 hashes per second. So, 1 hour later the network has the 37th and 38th block with `800 + 1000` score, and you have the 37th and 38th block with `1000 + 10` score. If you just ha…