[ETH_start]

>>Per your example, ok Apple Pay got cut off. Is the transit system going to support crypto? Will they be able to run their business and make that transition with regulators?

That's the big question. But assuming for a moment that crypto can act as a substitute for traditional centralized payment systems, then it has significant advantages in some contexts over those systems.

[tsimionescu]

> But assuming for a moment that crypto can act as a substitute for traditional centralized payment systems, then it has significant advantages in some contexts over those systems.

Except that, fundamentally, distributed permission-less systems can't come close to the computational efficiency of centralized systems. So this is like "assuming perpetual motion machines existed, we could build a post-scarcity society" levels of assumption.

[ETH_start]

I don't think that is established. Distributed and permissionless systems don't need to handle the overhead of access control. They do have the computational overhead of massive redundancy, but that can be significantly reduced with zk-(SNARK/STARK) cryptography that provides succinct zero-knowledge proofs of validity.

With zk-proofs, the redundancy of a blockchain can be significantly reduced without comprimising security. What redundancy remains provides the high process integrity that critical applications like financial transactions require.

[throwaway413]

Do you have any recommended readings on zk-proofs? Familiar with crypto, familiar with zcash, but haven’t looked into this enough and sounds promising. I am going to look into it.

It’s been around for a bit already, why is it not more widely adopted compared to BTC/ETH, any thoughts?

[ETH_start]

This is a good write-up on how zk-proofs can be used to increase the scalability of blockchains:

https://polynya.medium.com/rollups-data-availability-layers-...

zcash initially used zk-proofs only for privacy. It is only now looking to utilize it for scalability.