Once you control 50%+1 of the votes, you vote for forks that give you equal or more voting power.
Check-points can help guard against this, but can be a central point of failure if not carefully implemented (possibly leveraging the Bitcoin PoW blockchain).
what you are explaining is a 51% attack not a "history attack" which is what BombaUcigasa was trying(and failing) to explain and what you have just said does not answer the question i asked.
see this is what im talking about.. no one can provide
the math to prove this? or give a technical explanation of exactly how you would do thisshow the math and the technical explanation or its pure tripe.
You can't mathematically prove it, because the other stake-holders can roll back to any point of time of
their choosing.
In other words, PoS does not actually form a consensus.
Edit: I am not sure I understand the distinction between a 51% and "history" attack. The point of the block-chain is to document and order transactions.