Glossary
Nothing-at-Stake
A theoretical proof-of-stake flaw where validators face no cost to vote on every competing fork at once, undermining the chain's ability to converge on a single history.
The nothing-at-stake problem describes a weakness in naive proof-of-stake designs: because signing a block costs almost nothing, a rational validator can vote on every fork simultaneously to collect rewards no matter which one wins. Under proof-of-work the same trick would split a miner's limited hashrate, but staking has no such physical constraint.
If everyone hedges across all forks, the network struggles to reach consensus and becomes easier to attack. Modern protocols answer this with slashing, which destroys the stake of validators caught signing conflicting blocks, restoring a real cost to equivocation.