5 ms·

Empirical explanation for Craig Wright's selfish mining Bitcoin bet

35 points by grano 9y ago

tromp 9y ago
Closely related, [1] previously discussed the paradoxical fact that: If you pick a random point in time, you expect 20 minutes between the previous block and the next block on average. [1] https://news.ycombinator.com/item?id=16469382 https://news.ycombinator.com/item?id=16469382
- usmannk 9y ago
  Not quite. The paradoxical fact is that if you pick a random point in time, it’s expected that there is 20 minutes between that point and the next block. Even if there’s already been 20 minutes since the previous block! Edit: woops! See below.
  - tgb 9y ago
    The original poster had it right - you are mistakenly thinking that the block time is 20 minutes when it's 10. Once you make that correction, you are both correct.
- barbegal 9y ago
  And it's relatively easy to prove intuitively. If you pick a random point in time, the time from that point to the point of finding the next block will be 10 minutes. That is globally true. The point will also be randomly distributed in an interval, so on average there is as much time between the random point and the next block as between the random point and the previous block. Thus at a random point in time the average interval is 10 minutes + 10 minutes = 20 minutes.
barbegal 9y ago
Craig Wright would be correct if not for the information that the dishonest miners found the "next" block. If anyone could have found the next block and the dishonest miners simply found a block at t=0 then the expected time for the honest miners to find a block would be at t=5 minutes.
- madavidj 9y ago
  That is still incorrect. Assuming a poisson process, the expected time to find the next block from T+0 is T+15 no matter what information was given or not given. edit: and assuming 2/3 hashing power
- __blockcipher__ 9y ago
  Nope, this is totally wrong. To put it bluntly, please stop spreading this garbage. CSW completely misunderstood memorylessness (which, just to state the obvious, is solid bayesian evidence that he is not Satoshi). Regardless of the knowledge of the participants, it will always take an EV of 10 minutes when alpha = 1, or an EV = 15 given alpha = 2/3 in this example.
  - barbegal 9y ago
    I completely agree but in this formulation of the problem the honest miners started at t=-10 so may have found the block before the dishonest miners in the timeframe from t=-10 to t=0.
    - __blockcipher__ 9y ago
      They did not, that is (perhaps implicitly) part of the problem description. It never says the honest miner finds block N, it asks when they are expected to implying it hadn't happen up to that point. Also, the dishonest miner found the "next block" but did not broadcast it at t=0, which is essentially irrelevant information because it doesn't matter whether the honest miners know about the hidden block or not, either way it will take them an EV of 15 minutes at any given point in time regardless of knowledge
munro 9y ago
This makes me think of the classic Monty Hall problem, where Monty opens a door and asks if you would like to switch or stay.. which is actually giving you information that the door opened was a goat (which he had to do if you picked the door with the other goat). So when try to understand "how long until the block is mined?" at t=10, you're given information that the block has not been mined yet and have to update your predictions, thus making the average time from t=10 another 10 minutes away. The hard part I have internalizing is if I were to make a progress bar for block mining, it would be totally useless because it'd always show 10 minutes away, until BOOM it hits 100% when a block is found (or someone else does). Then I had a realization that it's the wrong question to ask because the time is truly unknown, but instead we could show a "progress" bar of the percentile! So starts at 0.1%, then 5%, then 50% (median time whatever that is). Thinking this way becomes very intuitive, because now you're no longer wondering when it will finish, but instead are given a benchmark of survival time and can think things like "crazy, only 1% of blocks have taken more than 40 minutes to mine." and at the same time get the piece of mind of seeing something "progress" while at the same time being comfortable that it will never finish, until it does.
- madavidj 9y ago
  It's almost like a reverse Monty Hall problem. In the Monty Hall, the extra bit of information seems useless, but is actually useful. In a poisson process, the extra bit of information seems useful, but is actually useless.
908087 9y ago
Something I've rarely seen asked in regards to the "Bitcoin will become the main global currency" fever dream fantasy is this: Who would want to live in a world where a new multi-trillionaire class is created out of thin air, particularly given the shady history of many who would be among those people? What blows my mind is that the people I see hoping for this are often the same ones claiming Bitcoin will improve global wealth inequality. If you think high wealth individuals have too much control and too little accountability now, just think about what would happen if people who hoarded Bitcoin drug profits and people like Brock Pierce suddenly held hundreds of billions of dollars or more, all of which was liquid.
- bdcravens 9y ago
  Not really sure how this comment relates to the submitted article. This feels more like if (HN_title.contains('Bitcoin')) { express_generic_opinion(); }
- test6554 9y ago
  The ranks of wealthy people are not chosen by a committee who get to vet them based on desirable traits. You either have wealth or you do not. The wealth either belongs to you or it does not.
- XR0CSWV3h3kZWg 9y ago
  > Something I've rarely seen asked in regards to the "Bitcoin will become the main global currency" fever dream fantasy is this Then you haven't been looking. At the end of the day expressing an opinion that the world shouldn't be a certain thing doesn't do much to prevent that from happening. Whats your plan for preventing what you laid out?
KirinDave 9y ago
I knew Wright was shady, but did he seriously bet that an exponential distribution doesn't have the properties it is known to have? Cuz, uh, wow.
CyberDildonics 9y ago
Don't promote this guy, it should be obvious he is a conman. He claimed to be the creator of bitcoin ten years ago using C++ and Qt, yet there is no other software that he has written anywhere to be found. He claimed he would sign a message with the private key from the genesis block, yet never did. Instead he used a previously signed message to dupe people. Here is a blog post that he edited to make it look like he was working on cryptocurrency in 2008: https://i.imgur.com/hAbPhW3.png https://i.imgur.com/hAbPhW3.png Here is a compilation of evidence against his claims: https://www.reddit.com/r/btc/comments/89bui6/buterin_about_csw_why_is_this_fraud_allowed_to/dwq8egl/ https://www.reddit.com/r/btc/comments/89bui6/buterin_about_c... He made these claims to get funding for his company which is now on a tear to patent everything they can: https://www.reuters.com/investigates/special-report/bitcoin-wright-patents/ https://www.reuters.com/investigates/special-report/bitcoin-... His selfish mining paper was also found to have large parts plagiarized from previous papers published in the 90s.
oh_sigh 9y ago
Wright getting simple math(relative to the math in Bitcoin) wrong is even more evidence that he is not Satoshi - not that anyone particularly needed more evidence

35 points by grano 9y ago

Closely related, [1] previously discussed the paradoxical fact that: If you pick a random point in time, you expect 20 minutes between the previous block and the next block on average. [1] https://news.ycombinator.com/item?id=16469382 https://news.ycombinator.com/item?id=16469382

usmannk 9y ago
Not quite. The paradoxical fact is that if you pick a random point in time, it’s expected that there is 20 minutes between that point and the next block. Even if there’s already been 20 minutes since the previous block! Edit: woops! See below.
- tgb 9y ago
  The original poster had it right - you are mistakenly thinking that the block time is 20 minutes when it's 10. Once you make that correction, you are both correct.
barbegal 9y ago
And it's relatively easy to prove intuitively. If you pick a random point in time, the time from that point to the point of finding the next block will be 10 minutes. That is globally true. The point will also be randomly distributed in an interval, so on average there is as much time between the random point and the next block as between the random point and the previous block. Thus at a random point in time the average interval is 10 minutes + 10 minutes = 20 minutes.

barbegal 9y ago

Craig Wright would be correct if not for the information that the dishonest miners found the "next" block. If anyone could have found the next block and the dishonest miners simply found a block at t=0 then the expected time for the honest miners to find a block would be at t=5 minutes.

madavidj 9y ago
That is still incorrect. Assuming a poisson process, the expected time to find the next block from T+0 is T+15 no matter what information was given or not given. edit: and assuming 2/3 hashing power
__blockcipher__ 9y ago
Nope, this is totally wrong. To put it bluntly, please stop spreading this garbage. CSW completely misunderstood memorylessness (which, just to state the obvious, is solid bayesian evidence that he is not Satoshi). Regardless of the knowledge of the participants, it will always take an EV of 10 minutes when alpha = 1, or an EV = 15 given alpha = 2/3 in this example.
- barbegal 9y ago
  I completely agree but in this formulation of the problem the honest miners started at t=-10 so may have found the block before the dishonest miners in the timeframe from t=-10 to t=0.
  - __blockcipher__ 9y ago
    They did not, that is (perhaps implicitly) part of the problem description. It never says the honest miner finds block N, it asks when they are expected to implying it hadn't happen up to that point. Also, the dishonest miner found the "next block" but did not broadcast it at t=0, which is essentially irrelevant information because it doesn't matter whether the honest miners know about the hidden block or not, either way it will take them an EV of 15 minutes at any given point in time regardless of knowledge

munro 9y ago

This makes me think of the classic Monty Hall problem, where Monty opens a door and asks if you would like to switch or stay.. which is actually giving you information that the door opened was a goat (which he had to do if you picked the door with the other goat). So when try to understand "how long until the block is mined?" at t=10, you're given information that the block has not been mined yet and have to update your predictions, thus making the average time from t=10 another 10 minutes away. The hard part I have internalizing is if I were to make a progress bar for block mining, it would be totally useless because it'd always show 10 minutes away, until BOOM it hits 100% when a block is found (or someone else does). Then I had a realization that it's the wrong question to ask because the time is truly unknown, but instead we could show a "progress" bar of the percentile! So starts at 0.1%, then 5%, then 50% (median time whatever that is). Thinking this way becomes very intuitive, because now you're no longer wondering when it will finish, but instead are given a benchmark of survival time and can think things like "crazy, only 1% of blocks have taken more than 40 minutes to mine." and at the same time get the piece of mind of seeing something "progress" while at the same time being comfortable that it will never finish, until it does.

madavidj 9y ago
It's almost like a reverse Monty Hall problem. In the Monty Hall, the extra bit of information seems useless, but is actually useful. In a poisson process, the extra bit of information seems useful, but is actually useless.

908087 9y ago

Something I've rarely seen asked in regards to the "Bitcoin will become the main global currency" fever dream fantasy is this: Who would want to live in a world where a new multi-trillionaire class is created out of thin air, particularly given the shady history of many who would be among those people? What blows my mind is that the people I see hoping for this are often the same ones claiming Bitcoin will improve global wealth inequality. If you think high wealth individuals have too much control and too little accountability now, just think about what would happen if people who hoarded Bitcoin drug profits and people like Brock Pierce suddenly held hundreds of billions of dollars or more, all of which was liquid.

bdcravens 9y ago
Not really sure how this comment relates to the submitted article. This feels more like if (HN_title.contains('Bitcoin')) { express_generic_opinion(); }
test6554 9y ago
The ranks of wealthy people are not chosen by a committee who get to vet them based on desirable traits. You either have wealth or you do not. The wealth either belongs to you or it does not.
XR0CSWV3h3kZWg 9y ago
> Something I've rarely seen asked in regards to the "Bitcoin will become the main global currency" fever dream fantasy is this Then you haven't been looking. At the end of the day expressing an opinion that the world shouldn't be a certain thing doesn't do much to prevent that from happening. Whats your plan for preventing what you laid out?

KirinDave 9y ago

I knew Wright was shady, but did he seriously bet that an exponential distribution doesn't have the properties it is known to have? Cuz, uh, wow.

CyberDildonics 9y ago

Don't promote this guy, it should be obvious he is a conman. He claimed to be the creator of bitcoin ten years ago using C++ and Qt, yet there is no other software that he has written anywhere to be found. He claimed he would sign a message with the private key from the genesis block, yet never did. Instead he used a previously signed message to dupe people. Here is a blog post that he edited to make it look like he was working on cryptocurrency in 2008: https://i.imgur.com/hAbPhW3.png https://i.imgur.com/hAbPhW3.png Here is a compilation of evidence against his claims: https://www.reddit.com/r/btc/comments/89bui6/buterin_about_csw_why_is_this_fraud_allowed_to/dwq8egl/ https://www.reddit.com/r/btc/comments/89bui6/buterin_about_c... He made these claims to get funding for his company which is now on a tear to patent everything they can: https://www.reuters.com/investigates/special-report/bitcoin-wright-patents/ https://www.reuters.com/investigates/special-report/bitcoin-... His selfish mining paper was also found to have large parts plagiarized from previous papers published in the 90s.

oh_sigh 9y ago

Wright getting simple math(relative to the math in Bitcoin) wrong is even more evidence that he is not Satoshi - not that anyone particularly needed more evidence