Bitcoin can be thought of as a clock, but the unit that is being transfered can't be thought as time because for it to be mappable to time, you need a linear function and Bitcoin's emission is exponential because of the halvings.
For what it's worth, I agree with you that Grin's emission scheme is the 'correct' one.
The effect of adding one coin to a pool of coins, on a steady schedule, results in inflation along a logarithmic curve. Inflation is about how much money is created relative to how much exists, so the second minute of Grin is 100% inflation, the third minute is 66%, and so on.
Also, people lose their cybercoins. It might average out that Grin hits a steady state, or even deflates a bit, depending on how frequently people or corporations lose their keys, die without heirs, send to a nonexistent address, and so on.
But even without this, the mining reward remains consistent even as overall inflation becomes negligible. Inflation never stops, but it does hit a point where it may as well have.
Bitcoin, by contrast, is guaranteed to be deflationary, and in fact the property that everyone holding BTC gets a permanent bump in asset value every time a bit of the ledger is lost strikes me as... moderately hazardous to the health of those who hold large allocations of the ledger.
I don't think this has much bearing on the article though, just wanted to tip the hat to another Grin respecter.
I'm glad you mentioned this. Indeed, there are two different things. First is the linearity of blocks and the second is the linearity of the emission of units with which we transact. Bitcoin has the former, but does not have the latter. You can't unambiguously say "I'm going to buy an hour of Bitcoin" because this hour depends on _when_ you plan on buying them - the emission over any time interval (including one hour) changes over time due to the halvings. This is why I think coins with a constant emission (especially Grin where 1 coin is emitted every second) can bring to life the saying "time is money" because money becomes time. There is no difference between calling your 100 Grins "100 Seconds" and buying an hour of Grin. So yes, you're correct that the article talks about the "block time", but I think this can be pushed further where you not only have a global clock for events, but your unit of money is time itself.
P.S. I prefer thinking of a blockchain as a "drunk" clock, because of the variance that comes with the finding of a valid PoW. It might sway a bit left and right, but it mostly goes in the straight line in the end.
Thanks for linking the Grin article! Now you've sent me on a rabbit hole reading about different emission strategies and ideas. (I follow Beam development, so I love to read about both projects).
Doesn't the consistent emission of Grin depend upon the number of users and transactions also rising at the same consistent rate? Can we really count on that like we can count on the ticking of time?
Glad to hear that. In Grin, each block creates 60 coins. The time to mine a block is set to be 1 minute on average, so it will average out as 60 coins each minute and hence 1 coin per second. This won't be _exact_ of course due to the variance in block times so you definitely can't count on that - just like you can't count on Bitcoin getting exactly 24*6 blocks each day. But these systems are defined such that if the blocks start coming in too fast, they make them come slower and if they are coming in too slow, they make sure to make the puzzle easier to solve so the blocks can come faster. I think this follows the models they have good enough.
That does seem like a cool feature. It just requires a bit of a mindset change.
Compared with gold, yes you can estimate when new gold is unearthed, but at the same time, there is a theoretical limit to the total amount of gold in the ground, right?
I don't think Grin does this but you can adjust the emission schedule based on the clock time (Sia does) so that the number of total coins produced on a given date is within a very tight bound of its expected amount, regardless of how much the hashrate has changed.
It's a stepped linear emission that mimics an inverse exponential emission. You can even see it in that chart if you expand it. Between the halving periods the emission is constant.
If you zoom in enough, you won't see these exponential steps. If you were able to zoom out completely, you'd see _only_ the exponential function. Bitcoin's emission is an exponential function (dropping exponentially), the fact that there is some time period between these exponential steps does not make it non-exponential. This would have been obvious if the halvings were every 30 minutes, but it's much less obvious when the "in-between step interval" is 4 years.
The block subsidy is constant between halvings. And is thus a step function.
But "emission" refers to cumulative block subsidies. And thus is piecewise linear, with 34 pieces of exponentially decreasing slope, the last one ending up flat.
Bitcoin can be thought of as a clock, but the unit that is being transfered can't be thought as time because for it to be mappable to time, you need a linear function and Bitcoin's emission is exponential because of the halvings.