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Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

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Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#41

Post by k_sze »

paulmendoza wrote: post #31
bluesign wrote: post #5

- I think 80 tons of CO2 for BTC is wrong. It should be around 15-20 tons (75% of BTC is mined with renewables, I think approx 20-25% is coal) - for US, CO2 per $ GDP should be around 0.3 kg - so if BTC is 50000$ value, it is almost same CO2 then something else US produce, (it would be 50000* 0.3 = 15 tons) - if we assume those numbers correct, lets assume they are both 15 tons, it means 50% of the things US produce…

That last point is key. Bitcoins once created exist forever.

Until somebody loses their wallet in a discarded HDD.

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#42

Post by AshamedCaptain »

paulmendoza wrote: post #31
bluesign wrote: post #5

- I think 80 tons of CO2 for BTC is wrong. It should be around 15-20 tons (75% of BTC is mined with renewables, I think approx 20-25% is coal) - for US, CO2 per $ GDP should be around 0.3 kg - so if BTC is 50000$ value, it is almost same CO2 then something else US produce, (it would be 50000* 0.3 = 15 tons) - if we assume those numbers correct, lets assume they are both 15 tons, it means 50% of the things US produce…

That last point is key. Bitcoins once created exist forever.

But obviously people will by then move into NewerCoin (TM) . Would there be _any_ reason, considering the primary motivations and utility behind bitcoin, not to do it?

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#43

Post by Imnimo »

SahAssar wrote: post #30
mensetmanusman wrote: post #21

Are there any good papers on the BTC network robustness in the event of war. It is well known that major military powers have the ability to cut essentially every ocean-floor optical fiber bundle handling the backbone of the internet at a moment’s notice. If this happens, how would the bitcoin network respond without active connections to other mining nodes? E.g. would the Chinese miners automatically (algorithmicall…

I'm guessing that when they all reconnect again the longest chain would win and basically all the other forks would roll back, so essentially only the transactions of the continent with the most hash power would stay. IIRC bitcoin does not have any conflict resolution besides "most work wins".

But won't each continent adjust its difficulty to account for its local hashrate? And would a high difficulty fork accept that a low difficulty longer fork is valid? Or would it reject it for having invalid blocks?

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#44

Post by Jimmc414 »

Hydraulix989 wrote: post #35
nooneiswatching wrote: post #27

Earlier quoted context omitted.

Very interesting thought. I believe that chains would initially split, effectively being forks of each other. However, the consensus algorithm of Bitcoin dictates that the chain with the most work is the valid one, meaning that in the event of a "reconnection", one of the chains would be abandoned (and everyone would agree which one to keep, namely the one with the most work). In the case of a total disconnect betwee…

Philosophical question: At what point do divergent chains become irreconcilably and separately valid? Is this a property we would ever want in a should-be decentralized currency? One way this can happen today is with intentional forks.

That is actually a good and very practical question.

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#45

Post by ashtonkem »

Imnimo wrote: post #43
SahAssar wrote: post #30

Earlier quoted context omitted.

I'm guessing that when they all reconnect again the longest chain would win and basically all the other forks would roll back, so essentially only the transactions of the continent with the most hash power would stay. IIRC bitcoin does not have any conflict resolution besides "most work wins".

But won't each continent adjust its difficulty to account for its local hashrate? And would a high difficulty fork accept that a low difficulty longer fork is valid? Or would it reject it for having invalid blocks?

The algorithm is tuned so that a block is mined about every 10min no matter what the hashing power available is. In the case of a serious and persistent network partition, both “sides” would continue to mine blocks at roughly the same rate as before, minus the first blocks that would take a while as the algorithm tried to catch up to the drastically reduced local hashing power.

The real issue is what happens once the partition is healed, and it’s not a technical problem. The technical solution is straightforward: longest chain wins. The real issue is a social one: how do you deal with finding out that the last N months worth of transactions are just gone?

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#46

Post by Imnimo »

ashtonkem wrote: post #45
Imnimo wrote: post #43

Earlier quoted context omitted.

But won't each continent adjust its difficulty to account for its local hashrate? And would a high difficulty fork accept that a low difficulty longer fork is valid? Or would it reject it for having invalid blocks?

The algorithm is tuned so that a block is mined about every 10min no matter what the hashing power available is. In the case of a serious and persistent network partition, both “sides” would continue to mine blocks at roughly the same rate as before, minus the first blocks that would take a while as the algorithm tried to catch up to the drastically reduced local hashing power. The real issue is what happens once the…

If I'm stranded in Antarctica, and decide to compute hashes with my pocket calculator to pass the time, and drop the difficulty to zero (because I can do one hash every 10 min, so they all have to be winners), does the bitcoin protocol say that my chain of empty blocks is a valid contender for longest chain? Or does "longest chain" also take into account difficulty? (Setting aside the obvious fact that in reality everyone would obviously just ignore me)

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#47

Post by ashtonkem »

Imnimo wrote: post #46
ashtonkem wrote: post #45

Earlier quoted context omitted.

The algorithm is tuned so that a block is mined about every 10min no matter what the hashing power available is. In the case of a serious and persistent network partition, both “sides” would continue to mine blocks at roughly the same rate as before, minus the first blocks that would take a while as the algorithm tried to catch up to the drastically reduced local hashing power. The real issue is what happens once the…

If I'm stranded in Antarctica, and decide to compute hashes with my pocket calculator to pass the time, and drop the difficulty to zero (because I can do one hash every 10 min, so they all have to be winners), does the bitcoin protocol say that my chain of empty blocks is a valid contender for longest chain? Or does "longest chain" also take into account difficulty? (Setting aside the obvious fact that in reality eve…

This isn’t quite how the algorithm works.

To make a valid block, you have to start with another valid block. The difficulty is set (edit: I was wrong, and I fixed this) every 2016 blocks based on how long they took to mine. This works out to about 2 weeks at the expected rate of mining. The average time of those 2016 blocks is then used to calculate the difficulty of the next 2016 blocks, and the difficulty is marked down in the chain itself.

So in your hypothetical you’d have to solve around two weeks worth of blocks at the current difficulty level, which isn’t possible in a human lifespan. After that the difficulty for your chain would rapidly fall, but your sub-chain would already be very far behind and would never catch up.

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#48

Post by benchaney »

Imnimo wrote: post #46
ashtonkem wrote: post #45

Earlier quoted context omitted.

The algorithm is tuned so that a block is mined about every 10min no matter what the hashing power available is. In the case of a serious and persistent network partition, both “sides” would continue to mine blocks at roughly the same rate as before, minus the first blocks that would take a while as the algorithm tried to catch up to the drastically reduced local hashing power. The real issue is what happens once the…

If I'm stranded in Antarctica, and decide to compute hashes with my pocket calculator to pass the time, and drop the difficulty to zero (because I can do one hash every 10 min, so they all have to be winners), does the bitcoin protocol say that my chain of empty blocks is a valid contender for longest chain? Or does "longest chain" also take into account difficulty? (Setting aside the obvious fact that in reality eve…

In practice you wouldn’t be able to mine at all, because the difficulty updates infrequently, so you would have to mine several blocks at the old difficulty. Obviously this is impossible on a pocket calculator.

I’ve always assumed that the notion of longest chain takes difficulty into account, although I haven’t really been able to find confirmation of this.

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#49

Post by Imnimo »

ashtonkem wrote: post #47
Imnimo wrote: post #46

Earlier quoted context omitted.

If I'm stranded in Antarctica, and decide to compute hashes with my pocket calculator to pass the time, and drop the difficulty to zero (because I can do one hash every 10 min, so they all have to be winners), does the bitcoin protocol say that my chain of empty blocks is a valid contender for longest chain? Or does "longest chain" also take into account difficulty? (Setting aside the obvious fact that in reality eve…

This isn’t quite how the algorithm works. To make a valid block, you have to start with another valid block. The difficulty is set (edit: I was wrong, and I fixed this) every 2016 blocks based on how long they took to mine. This works out to about 2 weeks at the expected rate of mining. The average time of those 2016 blocks is then used to calculate the difficulty of the next 2016 blocks, and the difficulty is marked…

That makes sense, I remembered that it adjusted every 2 weeks, but I forgot that the 2 weeks was actually measured in blocks, not wall time.

Re: Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

#50

Post by zMiller »

Articles like this while well meaning and coming from a good place are extremely naive and myopic. Do a bit of research in terms of the costs in lives and “, yes c02, of the current status quo and petro dollar complex. Do some research on how many human productive hours where lost in debasement and irresponsible monetary policy (fun fact the GFC cost around 70,000$ per American) I can go on forever and should you be interested id be more than happy to point you in the direction of sound research that has been done on this topic rather than this click bait
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