RE: Crypto's Achilles Heel 51% Double-Spending Attack Possible on Some Blockchains, Like BTG

[scalextrix]

51% hash power allows you to author every block in a row with a certainty of 1. 40% hash power gives you 0.5 certainty of mining 6 blocks in a row. There is a calculator online somewhere, can't find it now. This is why mining pools are such a disaster for PoW security.