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Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

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Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#61
post #38

Earlier quoted context omitted.

There was a much lower price point originally, before he got sort of famous from the book, and subsequently a TV-show (Going Deep). The current price is basically to keep people from ordering, but still having it open if someone REALLY wants to get one.

Honestly, what is getting me is that his book on sharpening pencils is actually 224 pages long. That seems awful long on such a simple subject!

I guess the joke is that sharpening pencils is what you do when you have writer's block, so if you really have writer's block, you write a whole book on sharpening pencils?

Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#63
post #24
post #9

Around when this was published I looked into the feasibility of pencil-and-paper wallets. What would it take to generate a key-pair using just pencil and paper? There are tricks like big tables of precomputed multiples of the generator that make it easier, but you still need to do hundreds of 77 digit modular multiplications. And you want to be absolutely sure you made no mistake.

Well secp256k1 private keys are just 32 random bytes (with some minor exceptions) so I think you could arrange something with a plain dice and a little bit of time.

Generating the private key is the easy part; Just 77 rolls with a ten-sided die and re-try if it exceeds the prime. Or 256 coin flips, if you prefer binary.

It is computing the public key that is so hard.

Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#64
post #38

Earlier quoted context omitted.

There was a much lower price point originally, before he got sort of famous from the book, and subsequently a TV-show (Going Deep). The current price is basically to keep people from ordering, but still having it open if someone REALLY wants to get one.

Honestly, what is getting me is that his book on sharpening pencils is actually 224 pages long. That seems awful long on such a simple subject!

There's only a few sentences on each page.

Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#65
post #9

Around when this was published I looked into the feasibility of pencil-and-paper wallets. What would it take to generate a key-pair using just pencil and paper? There are tricks like big tables of precomputed multiples of the generator that make it easier, but you still need to do hundreds of 77 digit modular multiplications. And you want to be absolutely sure you made no mistake.

may as well create and sign the transaction on paper also.

For signing, both your private key and a random number k need to be kept secret. The process then involves scalar multiplication, modular inversion and two more multiplications — strictly more work than generating a key-pair.

Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#67
post #9

Around when this was published I looked into the feasibility of pencil-and-paper wallets. What would it take to generate a key-pair using just pencil and paper? There are tricks like big tables of precomputed multiples of the generator that make it easier, but you still need to do hundreds of 77 digit modular multiplications. And you want to be absolutely sure you made no mistake.

A mechanical wallet would be awesome!

Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#68
post #9

Around when this was published I looked into the feasibility of pencil-and-paper wallets. What would it take to generate a key-pair using just pencil and paper? There are tricks like big tables of precomputed multiples of the generator that make it easier, but you still need to do hundreds of 77 digit modular multiplications. And you want to be absolutely sure you made no mistake.

It is theoretically possible, as there are just a few moving parts ( 2 tweets worth ): https://twitter.com/ribasushi/status/939954274569785344

Whether it is feasible... the amount of calculations around secp256k1 is likely practically prohibitive for pencil/paper.

Re: Mining Bitcoin with pencil and paper: 0.67 hashes per day (2014)

#70

>"Currently, a successful hash must start with approximately 17 zeros, so only one out of 1.4 x 10^20 hashes will be successful." Can someone elaborate on the math here? How do we get to 1 in 1.4 x 10^20 ?

Assuming uniformly random hashes, shouldn't it be 1/2^17?
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