I have read that a block contains several bitcoin transactions and an attacker can forge fake blocks.
Does these forged fake bitcoin blocks cost the attackers money for mining or was it just generated for free from the attacker node?
The blockchain is safe from attacks because the blockchain was programmed by Satoshi to validate and keep the longest chain.
So the forge block will disappear from the blockchain network. This is wonderful but what happens if an attacker forge bitcoin blocks?
I even read that some of these forge blocks can have 2 to 3 confirmations. Is this true?
So how do you identify these forge bitcoin blocks immediately?