What a completely-decentralized cryptocurrency might look like It occurred to me that a more useful cryptocurrency would be one which didn't require a network to validate transactions. It would consist of some kind of (self-mined?) token that can be proven to be unique and to be &quot;owned&quot; only by the holder and likely be associated with a wallet. Spending it would simply change the token so that it's associated with a different wallet. Something like this might be even more fungible than a fiat note having a serial number.
Has a white paper been released describing a token which precludes doublespending without needing a network, at least after it is initially created?
Sounds nice, but may pose some challenges.
HashCash, bit gold, and b-money all tried to use self-mined proof of work as cash directly. Those projects were unable to solve the doublespending problem as they did not feature a global consensus system. DigiCash on the other hand was able to solve doublespending but required a central operator to clear payments and issue new tokens—shutting down the operator meant that the currency stopped existing.
Bitcoin's great breakthrough was that it provided a practical solution to the doublespending problem without a single point of failure. It combines the strengths of the above two approaches into a system where network participants both issue coins and decentrally author the global state. The latter removed the need for a central operator, while still providing the referee function which enabled every participant to locally resolve the doublespending problem.
What you describe as

&quot;some kind of (self-mined?) token that can be proven to be unique and to be &quot;owned&quot; only by the holder&quot;

is essentially a description of the doublespending problem: how do you guarantee that a digital good cannot be transferred multiple times?
So, your proposal boils down to a suggestion that we would &quot;only need to find another, even better way of solving the doublespending problem&quot; and then we'd be able to create an even better cryptocurrency. Sounds about right, but might be a bit optimistic since this solution already took a few decades to emerge, and the requirements you describe sound a lot more challenging.