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Comment by practicalpants | Hacker News Reader

Fyi Bitcoin can be manipulated and your wealth effectively redistributed if more than 51% of miner nodes act adversarially. (By some calculations it's only 1/3 required). If entities with billions want to hack bitcoin they theoretically could.

Surprising many don't know that Bitcoin has these takeover risks.

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No, a 51% attack only allows the attackers to double-spend and block future transactions while they have control over the network.

Re-writing historical transactions from before the 51% attack is impossible, unless he can somehow re-write the hard drives in each node's computer.

https://en.bitcoin.it/wiki/Weaknesses#Attacker_has_a_lot_of_...

I disagree with the "only", yes if a capital-intensive takeover happened they cannot take your bitcoins from your wallet, but they can still straight up destroy bitcoin or quietly enrich select parties through double spends as btc inflates.

Fwiw the history can be re-written if over a long time a miner produces a longer chain due to hash power advantages in secret; when released it would by default invalidate all transactions since the secret mining began.

Those entities with billions COULD do that, fully aware that it would utterly wipe out their billions in BTC assets. So why in the world WOULD they choose to do so?

When it comes to having control over a society I don't think some of these powerful groups care about wiping out a few billion. See covid-19 extended economy shut downs.

unlike other economies that are resistant to manipulation from majority stake holders?

I suspect this line of thinking will usually end with "world economies are backed by military groups.", to which I have no rebuttal.

Not saying Bitcoin is worse just that its vulnerable... Since we don't know for sure who controls what hash power, it's even possible that quiet manipulation already takes place.

On brighter side blockchain projects that require memory bound hashing algorithms are less vulnerable to takeovers since massive ASIC farms don't work afaik. Ethereum is one such approach (but ofc when they decided to undo transaction history after TheDao hack, it isn't immutable either).

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