I can not actually get my head across the empty block factor. I do not see the purpose in doing that. If an empty block goes onto the chain, it should nonetheless comprise the hash of the earlier block, and the following block has to comprise the hash of the empty block.
All an empty block would do is trigger everybody who’s mining to must restart mining once more as a result of the hash has modified. The rogue state would even have to begin mining from the present block too.

However as I perceive it, each transaction within the block can also be signed by the proprietor of the pockets with their secret key. So they may solely forge transactions if they’d entry to everybody’s secret key. I might be quick sighted right here, however the one factor {that a} 51% assault can obtain that I see is reversing transactions (by publishing a block-chain that ignores the unique transaction). If they’d 51% and will beat the community to publishing transactions they may money of their bitcoins, obtain the fiat cash or items, then return to the block earlier than their transaction and mine a brand new block with out their transaction printed.

It is one of many causes they are saying you must wait as much as 7 blocks to verify one thing is de facto, actually locked in. To undo that, the rogue state with 51% processing energy would wish to begin from 7 or 8 blocks again and begin mining blocks till they’ve extra blocks than the present chain. The unique chain continues to develop, so it turns into a race for the rogue state. They must catch up, then over-run the unique chain. The protocol dictates that the LONGEST fork of the chain wins. So that they must overtake it, after which I presume announce to the community that they’ve rejoined. Everybody then sees they’ve an extended chain that begins from that seventh or eighth block again they usually settle for it because the king.

To carry out this assault, not solely do you want greater than 50% processing energy however you additionally want to make sure you keep forward of the processing energy. You could possibly have 51% however then a bunch of energy is added to the 49% and the stability has gone from 51:49 to 48:51.

Additionally, I’m not 100% positive however there’s the mechanism to extend complexity when blocks are found too rapidly. It is not modified usually from reminiscence but when the common block creation is lower than 10 minutes then complexity will increase to make it more durable. I believe this mechanism can be ingrained within the rogue states chain as nicely so whether it is trying to carry out this over a protracted interval there could also be a difficulty with the complexity not matching as much as what it ought to and it might be rejected by the community when becoming a member of.

All thought of I do not actually have a lot information of the workings of Bitcoin however I joined right here to ask just a few questions and felt like I had one thing to contribute right here, so I hope that helps. Take it with a grain of salt.