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Is there any possibility for one token (e.g. Augur's REP) to become more valuable than the total Ether market cap? If so, how would that be possible?
In Security of PoS if/when Assets (Tracked or Native) to Ethereum exceed the total Value of Ether, the security of the asset(s) whose total value is greater than Ethereum's is discussed, but not the mechanism through which such a scenario could arise.