Is Selfish Mining Common in Cryptocurrencies?

Many cryptocurrencies rely on a system called proof-of-work. This means certain people, often called miners, solve complex math problems to validate transactions. It’s thought that this system is secure because miners are rewarded for following the rules. But there’s a worry that some miners might try to cheat by keeping their new blocks secret. This is called a selfish mining attack. To find out if this happens, researchers looked at five popular cryptocurrencies: Bitcoin, Litecoin, Monacoin, Ethereum, and Bitcoin Cash. They used a statistical test to see if any miners were acting strangely. They also used a method called address clustering to make these behaviours more visible. Interestingly, they found that some miners in Monacoin and Bitcoin Cash were acting suspiciously. There were also some signs of this in Ethereum. Moreover, they discovered that in Monacoin, some miners might be secretly working together to share information about new blocks before everyone else. This research is important because it shows that these cheating strategies do happen in real life. It raises questions about the security of cryptocurrencies and how we can prevent these attacks in the future.