How do you modify a transaction that occurred 100 blocks ago? You’d have to also modify the 99 other blocks since that modification. But for those new blocks to be valid you need to find the new magic number that brings the hash below a certain threshold, 99 times. But there aren’t enough machines.
False.
How do you modify a transaction that occurred 100 blocks ago? You’d have to also modify the 99 other blocks since that modification. But for those new blocks to be valid you need to find the new magic number that brings the hash below a certain threshold, 99 times. But there aren’t enough machines.