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When the host explains double spend around 22 minutes was just great!!! She gets it!!!
well done @ioptio !!!
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This video is fantastic. But what does half a trillion safe coins mean? Tell me like I’m a 5 year old.
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Except the part about adding probabilities 
One can’t do P = P1+P2 with probabilities 
I believed she quoted the wrong number for 2^32, which is in the 4 billion range, not in the 400 billion. Also, US billion, not UK billion (which is 1000x as much as the former.)
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4,310,000,000ish correct?
Google tells me it’s 4,294,967,296.
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Divisible to the 43rd decimal I think
i believe she was referring to the supply of MAID which is around 450m, not to the future suppy of Safecoins…that would be half a billion though…not trillion…
She did both. 14m15s – “How many safe coins will there be?” – “430 billion-ish”
Next question: “Is this the same number of how many Maidsafe coins …?” For which she responded with something like “no, it’s just a fraction.”
Then, the other lady asked her “so are these 430 million coins …”
There were many arbitrary numbers thrown around in that section
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I remember seeing a post about that it can be halved again and again, to an almost arbitrary depth. I can’t remember what was limiting the number of divisions in the end. 43 decimals equal to something around 142 consecutive halvings; if that’s the number, I can’t imagine why 
One was dividing using the other 32 bits, so 1/4billionth. But that would require one SD per 1/4billionth, and as anyone can imagine that is a lot of SDs to create
I suggest another solution that simply meant that everyone has a SD associated with their SAFEcoin account that holds a number representing the fraction of a coin in their account. Kept as a fixed point decimal
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Another way is to relax precision. Actual payments don’t usually require 32 bits of precision; something like 24 (or even 16) is enough, and then we could use the remaining bits to store the exponent. Then you can use a kind of floating point system to represent given amounts of coins of different denominations. In the rare cases when one needed more precision, he could combine two separate payments. But I may think in bitcoin terms, where the “coins” themselves are not numbered…
Well the idea was for SAFEcoin division. When amount >= 1.0000…000 then a coin is unfrozen and the amount reduced by one. If a subtraction gave < 0, then one of the safe coins in the transaction is frozen and 1 added.
And use a 64 bit signed integer (so simple add/subtract can be done) which allows a representation of an 18 digit fixed point number. 64 bit to future proof it and could use 128 bit if want it forever proof.
thus 0.2 SAFE coin would be 200000000000000000 (2 & 17 zeros)
+ve numbers only are stored in the SD
And to prevent some attacks like ballooning each account usually has one “coindust” SD and always used in transactions where fractions of a coin are involved. It is handled by the same core code as for coins.
Additionally to help prevent those attacks we need to limit the precision to a level that the system can handle additional SD’s created etc. So initially we could see 2 places and they can be SAFEcents.
So to store 2 SAFEcents 0.02 SAFEcoins is 20000000000000000 (2 & 16 zeros) stored in the integer. So the system allows 0 to 10000000000000000 to 990000000000000000 100 values effectively in steps of 1000000000000000
Later on we could decide to have 3 places or 6 places, and the core code has that precision changed during an update. There is no issue with the current values because all we’ve done is simply allowed more places. 1 SAFEcent is still same number stored
And a configuration parameter in the client can define how the decimal places are shown to the user. Just like most programs allow different date formats.
Total supply of maidsafecoin is 453 million and total supply of safecoin is 4 billion. Assuming safecoin to be more than $1/coin marketcap must be over $4 billion when the total supply of safe reaches 4.5 billion and all safecoins are mined.
If it reaches around $4B in marketcap when the total supply of safe is less than the total capacity the the price would be more than $1/coin. If all this weird stuff I am saying actually makes sense then why is it so hard for her to believe that it could be a very possible problem that safecoin will go over $1/coin.
If you’re referring to Paige, she thought there would be 430 billion safecoins in the future 
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Re: number of coins… oops! Never got the number stuck in my head and I tend to guess because it’s not that important. But I promise to remember now!! Actually, at Liberty Forum when I was talking to Amanda, she asked the same thing about number of coins and @frabrunelle was right next to me and had the answer but it didn’t stick then, either. 
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This sounds very different from the original whitepaper (referenced from this short thread), where it’s talking about strictly binary subdivisions (i.e. no decimal places, just consecutive halvings.) However, the whitepaper isn’t talking about coindust either, so maybe things have changed since.
As for my idea from above, each coin (whole or subdivided) is a uniquely numbered, fixed sized unit, so there’s no way to express something like “a coin that is worth 17 x 1/4th of a safecoin.” Which is a pity, but is also a reasonable limitation based on the (pretty clever) addressing scheme that’s being used.
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Yes, that was my idea to solve the possible number of SD objects needed for SAFEcoinage being 4 Billion * 4 billion subdivision when doing a full binary subdivision.
My way means one extra SD per account rather than expanding to a possible 16 billion billion SD objects which would be a nightmare.
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Oh okay, I get it then. Well, the possible number is unimaginable vaster than just 16 billion, by the way 
The good news is that it would be done on a “need to” basis, so there’s less reason to panic. The bad news is that I can’t see a way to “un-split” coins: it’s unlikely the two halves would end up in the same hands ever again, so: once split, always split.
Bitcoin’s model, where coins are just an abstract idea, and only transactions exist, is better for expressing arbitrary amounts, but Safecoin’s model of “actual coins” is probably what makes it possible to use it as truly anonymous cash.