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    An important notice, since it is buried at the end: xor filter is immutable. You can’t add or delete items once it is constructed. (You can’t delete in Bloom filter either, but you can add. Counting bloom filter supports both, but with worse overhead.)

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      In theory you create Bloom filter that would allow for removal of the entries (if you are sure that the entry was previously added). Just instead bits as flags you store count of elements that has that flag. Unfortunately that enormously increase the size of the filter.

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        If you want a filter which supports both adding and substraction with log(n) space, take a look at this new datastructure: Utreexo https://eprint.iacr.org/2019/611.pdf

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        I’ve been using TabNine for some time now (just package install it in Sublime text), it’s amazing what it autocompletes sometimes.

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          Agreed. I’ve been using it since it was announced and it’s very nice.

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          Oh great, another currency. I’m so excited. The world really needed facebux to solve its problems.

          At least it’s not PoW I guess.

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            I believe the technically correct name is “ZuckBucks”.

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              Why is that so good, PoW would actually make it decentralised.

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                Because PoW is an absolute waste of electricity engineering solution to a social problem. Have you ever wondered how much “mining” is done off coal power? Are there no ethical qualms there?

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                  Why would it be a waste, that is just relative to the utility of what it is used for. Currently Bitcoin uses an amount of electricity infamously likened to the electricity usage of Ireland. That sounds like a lot but you have to know it is only household electricity usage (not cars/transportation/industry) and Ireland has 5 million people, which use on average about 1/4 of electricity of a typical American. So we are really talking about household usage of about 1 million Americans. For that you get a completely decentralised currency, the utility of that far outweighs that tiny amount. The power usage also does not have to increase, the amount of computing power behind mining only has to be big enough that a large player (say NSA) can not take it over. And it is powered by electricity, using the cheapest electricity possible, so there is no reason to think it uses more coal than say a Tesla. In fact it is more likely to use renewables and take some unused capacity in peak times, since that is cheaper.

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                    You missed the part where I considered PoW a wasteful non-solution in the first place. However you want to measure up the power consumption, it is substantial. And imo, it’s for solving an imaginary problem, and really just lends to making early adopters money. You’re arguing past me here is all I’m saying. Whether the electric usage is one Ireland or three Irelands, it’s still on the scale of an entire country’s electricity, and it still puts carbon in the air, all for ludicrous magical thinking about the relationship of regulatory bodies, fiat, and exceptionally privileged and sheltered notions of “freedom”.

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                      Well if your position is to assume cryptocurrencies are useless, and you have a better consensus mechanism (it seems you like consensus by centralised authority) then yeah, there is not much to argue there. All I can say is that the majority of the world population does not need to be convinces that depending on currencies of your government is dangerous and alternatives are needed, we are in privileged positions where the euro / dollar has been relatively stable for now, although we’ll see how long that lasts.

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                        Those privileged and sheltered notions of freedom - i.e. the ability to transact digitally even if government and corporate regulators have it out for you or don’t care about whether you fit into their systems - are important, and worth some of the world’s electricity. You can get electricity by other means than burning coal, and providing for the existence of industrial civilization while moving off fossil fuel power is a problem humanity needs to solve regardless of whether or not PoW cryptocurrencies exist.

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                          You can get electricity by other means than burning coal

                          Ok, but the majority of society runs their power off fossil fuels. This is more magical thinking, when I’m talking about what currently is the state of things. PoW could be ran off clean energy! It could somehow make the world more free in some abstract magical way that anyone is yet to have really made clear and concrete to me! But meanwhile millions of lives are in the crosshairs of disasters driven by climate change, and first world libertarians have made obvious through their priorities they are more concerned about their LibertyBux than those millions of lives. It’s telling.

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                            Exactly - everything electricity-powered in our society runs largely off fossil fuels, and switching to renewable electricity generation sources is important for everything electricity-relatrd that anyone might want to do. Saying that something uses a lot of electricity is a fully-general argument against anything you don’t like. Maybe you don’t like video games so you say that climate change implies that it’s wrong to allocate electricity to all the video game consoles and gaming PCs and GPU chip fabs out there.

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                              🤯

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                                @kel there’s no reasoning about this with PoW proponents. Within the framework of blockchains secured by PoW the expenditure of energy is the whole point.

                                FWIW, there are a lot of other human endeavors with questionable value to society that expend a lot of energy - online gambling, cultivation and manufacture of illegal drugs, delivering adult entertainment online. PoW blockchains are just another expression of that, and not very large in the grand scheme of things.

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                                  Very true.

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                I’m mostly surprised how low on details the paper is. How are the coins distributed, how are transactions verified, how decentralised is it? I’m guessing it’s gonna be essentially facebook who signs transactions and the plebs can only hope their transactions will get it.

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                  Speculation follows (I have better things to do than to read marketing copy in the form of white papers)

                  In BTC terms, all wallets are SPV wallets.

                  The transactions will not be public, that would be a massive privacy issue as each wallet can be tied to a FB/IG/Whatsapp account.

                  Issuance will be at the discretion of the entitiy that’s tasked with keeping the ZuckBuck (Z$) stable against its basket of currencies. So it will be dictated by the forex markets.

                  The transactions will be seen only be the partners, mainly as a way to keep each other in check, and for netting - see below.

                  For the end user, it will be seamless - they send Z$ to someone else, it arrives instantly. No confirmation delays. This will be accomplished by netting between the participating partners.

                  Transactions will probably not be irreversible, because as soon as some poor tyke loses their Z$ pocket money to some Pokemon Go clone scam FB will face a massive publicity backlash.

                  Don’t expect to be able to buy pr0n, drugs, alchohol, firearms, or send money to Lashkar-e-Taiba.

                  In short, this is an attempt to be able to mint money without being burdened by banking regulations.

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                    Yeah I think you are right, still competition in this space of federated currencies is still a good thing. I would applaud anything that can compete with the domination of credit cards taking 3% of every transaction while consumers pretend ‘I don’t pay it, the retailer does’, sucking value out of the economy. If anything, this at least makes people think about what a currency is.

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                      Sure! Of course VISA is a Libra participant so value will be sucked out regardless.

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                    I’m guessing it’s gonna be essentially facebook who signs transactions

                    I don’t want to bore myself with rereading it but the consensus section basically alludes to this, although Facebook is not named

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                    This guy was really amazing, bordering between complete insanity and creativity. His story really needs a whole documentary one day.

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                        I feel that “documentary” focuses too much on the (very much real) decline of his mental health and his very public interactions (mostly the negative ones and those with trolls, which had the most outside attention), and not nearly enough on his life and work and actual beliefs and output.

                        While not overly offensive, I think that most people would just get the impression of “oh, crazy person”, and while he might have been partly the case (he even acknowledged it - sometimes in a joking manner, sometimes somberly), that shouldn’t define who Terry was, because he was much more than that.

                        He was never fully incapacitated, as he was very much aware of his disability, and while he wasn’t always able to be in control of every moment, he was never completely unaware or blind to his mental state and level of functioning.

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                          That gap in content is what I hope to fill. It’s hard for people to understand operating systems and the massive amount of work they take to make. That youtuber was really trying to make content catered towards his audience first and foremost.

                          The crazy people are the ones who literally see and experience things we do not. Hell when I had a crazy bout I was painfully aware of it. I personally view Terry Davis as a source of inspiration for how to design simpler and more resilient technology, if only because of his bout with insanity.

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                          Damn how didn’t I find this before! thanks!