My point is that unless the currency fluctuation is extreme to the point of causing general economic malaise, then the users of that currency as a unit-of-account have no appreciable individualized risk risk w.r.t. to the international exchange fluctuations.
I got your point here and it's perfectly acceptable for me. I have some doubts if it's possible for a cryptocurrency to become that stable (that's why I mentioned national fiat currencies). Ideally it should be that way, yes. I don't want to profoundize this issue because I think it's not that relevant for the discussion of Proof-of-burn's security.
Thus if a crypto-currency is intended to become a currency (e.g. a unit-of-account), then the "nothing at risk" will apply and my point is the "rich get richer" applies.
So let's take an ideal crypto-currency without significant price variations. Then the risk still is larger than zero because Proof of Burn does not return you exactly what you deposited, like Proof of Stake does. There are several variables that have incidence, being the most important the fluctuation of the amount of total "burnt" coins (if you burn, you cannot predict if there will be larger burns in the near future that may affect your profit).
In short, I don't see how adding risk to stake or burn deposits improves the issues with "nothing at stake" and advantage to those with the most to stake.
Here i think you misinterpreted me (I am sorry, I am not a native English speaker). I don't think PoB improves over PoS when considering the Nothing at stake problem. What I think is that in PoB there is a less direct relation between wealth and mining/minting rewards. That whole sentence was an answer to clemahieu's posting.
I also am aware of the "Short sell / Pirate attack".
It is a simple fact that volatility declines with increased liquidity (participation) and thus price. So by definition a more volatile and risky investment will have a smaller market cap and thus less security (relatively speaking). Even in my proposal to use "inertia" at the objective metric of consensus, the larger the participation, then the stronger the security of more inertia (at least the "inertia" I have in mind scales by n2 though).
That's completely true, my intention was not to put this into question.
Whereas, your described a design where risk declines as value increases, thus your security that depends on risk declines as the value increases which could provide more security. So you have two things working against each other in that design. Seems flawed.
That would be totally flawed, I agree
. But again, you misunderstood me. The equation of the Slimcoin and similar PoB designs is not "more risk - more security". It is totally true that in a mature market with less volatility also in Slimcoin's design the security is higher.
Perhaps I was not clear enough to make this distinction: In the first stage of a cryptocurrency - talking about the first six months, for example - in a Proof of Burn design like Slimcoin's, there
can be a high participation rate although the value still is small and volatile. In Slimcoin, this ocurred, because many people saw burning in the first stage as an opportunity to grow their amount of coins and speculated on a increasing or at least stable price. But that does not mean that it's security is higher in this first volatile phase. First, because in a mature market participation should be high too because of the lesser risk, as you correctly point out, and second, because of the then probably higher price of the coins you must burn to have a possibility to attack the chain.