Forking Bitcoin how to prevent a 51% majority attack Lets say I fork Bitcoin, to lets call it StackCoin. How do I prevent a 51% majority attack when miners are not in abundance? Would I have to setup a lot of miners to create the infrastructure of the network?
How do I prevent a 51% majority attack when miners are not in abundance? 


If an amount of hashpower larger than your network decides to 51% attack, there isn't much you can do. Ways to mitigate this include:

-Using a hashing algorithm that does not place your miners in direct competition with a larger coin (note: relevant to ASIC mineable coins more than GPU mineable)

-Enticing a group of miners to join your network right off the start

-Create a coin with a unique value proposition, so that others are less likely to attack. A coin that wants to directly compete with btc may be attacked by btc miners, for example. 

Remember that an attacker has opportunity costs to consider, if it is more profitable to just keep mining another coin, rather than destroy your network, then you'll have a better chance of bootstrapping your network.  

There are likely other ways you can introduce (centralized) 'administrator controls' for your network, but I won't go into any details on those, as such a system would be counter to the ethos of cryptocurrencies in the first place.