Nothing at Stake Problem

The nothing-at-stake problem is a theory speculated by the crypto-community in the Proof of Stake space. Unlike Proof of Work (PoW), PoS doesn’t require computational power in order to validate transactions. Therefore, in case of a potential fork in the blockchain, a PoW-powered blockchain incentivize validators to mine over a single chain since maximum computational power maximizes their chances of earning a reward. Whereas, in case of PoS-powered blockchain, a validator or stakeholder would not be incentivized to only resume staking ETH on a single chain but may choose to do on multiple chains creating a greater likelihood of attackers or mal-intent validators to spent and then fork the blockchain, since they would have nothing to lose, or as the theory puts it, nothing at stake.