This is not a very good explanation, but basically, you can have a "currency" using just asymmetric key cryptography: users simply sign "transactions". The problem is that you need a central authority to confirm the order of transactions, otherwise the recipient of a "transaction" will not know if the funds associated with that transaction have already been spent to someone else ("double spending"). You can solve this using hashcash to make the transaction order hard to reverse- creating a "proof-of-work" by doing something that is easy to verify but hard to determine (like reversing a hash function). Another method is "proof-of-stake" wherein transaction order is not signed by a central authority but instead general users that are guided by some internal incentive structure.
Cryptocurrency is often expensive to run or use because a cryptocurrency transaction has to be synchronized across the entire network of that cryptocurrency, and there are incentive structures like fees to prevent people from spamming the network.
There is also tech like zero-knowlege-proofs, multisig, etc. that can do interesting stuff. But this is the basic concept.
Is there any research on cryptomoney with central authorities, but also with reduced attack surfaces on a whole system? E.g. authority may be cryptographically bound in some way to only store the database and emit new tokens, but cannot spend them because they get freeze-signed by a receiver to their wallet. Then when you get a payment you check the path of money and algorithmically accept that path only. Anyone who accepts a similar subpath is on their own, because it is double-spending. Subpaths within few minutes self-cancel to prevent instant double-spend.
This is just a vague example, not a working idea. The point of it is that the level of security and trustlessness is not always required to be absolute. E.g. even with fully-secure pow crypto we still have to trust non-crypto claims about usdt, [non?]shitcoins, “hot” wallets, and other maybe-not-ponzis.
Yes, see David Chaum's original pre-bitcoin "e-cash" and the more recent GNU Taler project: https://taler.net/en/
The problem is that banks won't implement these systems unless they're forced to. They seem to benefit from the insecurity, surveillance, and bureaucracy of the existing system. So we will have to make new banks...
Perhaps CBDCs (Central bank digital currencies) are close to what you're looking at, the concept being digital money issued and verified by a central authority. There's been a bunch of research done by the central banks of various countries e.g.
This is not a very good explanation, but basically, you can have a "currency" using just asymmetric key cryptography: users simply sign "transactions". The problem is that you need a central authority to confirm the order of transactions, otherwise the recipient of a "transaction" will not know if the funds associated with that transaction have already been spent to someone else ("double spending"). You can solve this using hashcash to make the transaction order hard to reverse- creating a "proof-of-work" by doing something that is easy to verify but hard to determine (like reversing a hash function). Another method is "proof-of-stake" wherein transaction order is not signed by a central authority but instead general users that are guided by some internal incentive structure.
Cryptocurrency is often expensive to run or use because a cryptocurrency transaction has to be synchronized across the entire network of that cryptocurrency, and there are incentive structures like fees to prevent people from spamming the network.
There is also tech like zero-knowlege-proofs, multisig, etc. that can do interesting stuff. But this is the basic concept.