sharding has the same problem: if you want to check whether a coin has been double spent, then you need to go look at all the relevant shards anyway. http://di

sharding has the same problem: if you want to check whether a coin has been double spent, then you need to go look at all the relevant shards anyway. http://diyhpl.us/wiki/transcripts/scalingbitcoin/sharding-the-blockchain/ http://diyhpl.us/wiki/transcripts/scalingbitcoin/sharding-th...