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Comment by seanalltogether | Hacker News Reader

"It seems disappointing (?) that significant chunks of the finite amount of possible Bitcoins might be lost 'forever.'"

So I'm kinda curious, as the power of the collective network grows, how difficult would it be to turn the incredible hashing rate toward discovering the the private keys of wallets lost long ago?

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Hashing doesn't help you crack private keys. Bitcoin uses ECDSA to sign transactions, which means you need to be able to solve the discrete logarithm problem over an elliptic curve. In any case, even the combined computational resources of the entire planet probably aren't enough to break a 256-bit ECDSA key in a reasonable amount of time.

True, if by "break" you mean "break by brute force" (and of course with current, non-quantum computing technologies).

Most one-time pubkeys are wrapped in RIPEMD-160 and SHA256, so you have to crack those first before you even get to cracking ECDSA. This also offers temporary protection against sudden appearance of quantum computer. QC can break ECDSA, but cannot break hashes fast enough. So people would have time to switch to another algorithm or at least agree on the last valid blockchain state and stop all transactions.

The protocol could be updated to allow "mining" of addresses that didn't move for sufficiently long time. But that's never going to happen.

The interesting thing here is that Bitcoin isn't set in stone to forever exist exactly as it does today — it depends on the majority of miners not modifying the protocol. I'm talking about what's essentially a 51% attack, but rather than it being performed by a malicious party, what if a technical/political decision with very strong opinions on both sides had to be made? It would be like a democracy where those with the most computing power win.

Or most money, or depending when it happens, most guns.

I suppose you could try and reach a consensus when possible, rather than have a majority dictatorship.

I wouldn't see any real opposition to changing the protocol to allow mining of lost coins for example if some precise and correct definition of a lost coin could be specified.

How do you know if the wallet is lost? I'm guessing most people who lost their wallets, probably lost their public address too. (Unless they were using it as a donation sink or something). Plus, if you can crack the keys, you would just target the biggest wallet and be done with it.

I imagine that cracking wallets that have been dormant for a long time carries less risk of being noticed and/or caught.

Cracking a wallet can be done completely offline. I guess if you mean extracting the coins, yeah. I suppose that's what you'd use a bitcoin laundry service for. (a "mixer" I believe)

There's no difference between a lost bitcoin and one that is unused.

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