Out of curiosity I just thought where do bitcoins came from??

Person A deposits $100 in a bank, which means he has $100 he can spend. In accordance with Federal Reserve regulations, the bank is allowed to loan up to 90% of this money to someone else, say, Person B.

Once Person B has $90 in his bank account, this makes a total of $190 available to be spent. But his bank can loan up to $81 (90% of $90) to someone else. Now a total of $271 is available to be spent. And so on.

Great to see such a pre-eminent organisation releasing papers, and in draft, for free.

Not having yet read the paper, but commenting purely on the picture:
The similarity isn't accurate: An individual of moderate means can still afford to contribute meaningfully at the ASIC level for BITmining, unlike gold mining.
Basic infrastructure for an ASIC can cost about $1k with a moderate-low ROI, but still some ROI, unlike Gold mining at the pit mining level. Even 1 truck, or digger is so unfathomably beyond reach of the average joe it is just ridiculous.

The scales just do not compare.

Crash