What Is the “Nothing-at-Stake” Problem and How Do PoS Protocols Address It?

The "nothing-at-stake" problem is a theoretical issue in early PoS designs where validators, facing a chain split, have no cost to validate on both competing chains. This could prevent the network from reaching consensus.

Modern PoS protocols solve this by implementing 'slashing,' which penalizes validators who sign blocks on multiple competing chains, thus creating a financial cost to misbehavior.

How Does ‘Slashing’ in Pure PoS Systems Attempt to Solve ‘Nothing-at-Stake’?
What Is the ‘Nothing-at-Stake’ Problem in PoS?
What Is the “Nothing at Stake” Problem in Proof of Stake?
What Is the ‘Nothing at Stake’ Problem Unique to Some PoS Systems?
How Does the “Nothing at Stake” Problem Challenge the Security of Some PoS Implementations?
What Is a “Fork Choice Rule” and How Does It Prevent the Nothing-at-Stake Problem?
How Does the “Nothing at Stake” Problem Relate to PoS Security and Forks?
What Is the “Nothing at Stake” Problem in PoS and How Is It Addressed?

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