I have seen numerous sites referring to sealing a block and mining a block. I understand a miner seals a block but I do not really understand what sealing actually involves.
On that point, how does the VM actually know that a miner was 'first' in PoW consensus algorithms?
I assume a miner could just fake a response and listening on the network and then taking the correct answer and presenting that as the miner's own one.
The VM must have a means of controlling this.
On another related issue, the question of validation has come up. Is a validator a miner in a PoW based network?