" approximates the rate at which commodities like gold " are mined. I keep seeing this, and this is in the Bitcoin wiki. But we always mine 1% to 5% of the total gold supply per year?
It's a poor analogy. A really poor analogy. When people say that, the idea they are trying to get across is that there is a limited total supply available to acquire and that initially access to that supply is eaiser. As time goes on, the easy to access supply is all acquired, and the remaining supply becomes progressively more and more difficult to get.
How does double hashing protect against birthday attacks? Never been able to see this explained on the internet no matter how I google search.
As far as I know, double hashing does not protect against birthday attacks. Where did you hear that?
The protection against birthday attacks is the incredibly large number number of possibilities in the address set, and a (hopefully) even distribution of addresses across all 160 bit values.
