You can’t really have identifiers in JSON-LD without using URIs which have information in them.
I know Mikeal Rogers when at Protocol Labs was working on JSON-LD over IPFS, not sure how far they got, but even then, an IPFS content hash or alias probably also has the same problem with carrying information
And that’s part of the problem. This problem seems so ingrained in ActivityPub that I don’t see any way to fix it in a backwards-compatible way. It seems like to fix this problem, a breaking protocol change or a new protocol (same thing I guess) would be required. Just another reason to eschew JSON-LD (see also Desired changes for a future revision of ActivityPub and ActivityStreams).
Yeah, but everything would need some form of addressing to resolve what a thing is. Whether that’s content hashes, URIs or something else. And with pure JSON, you still need to put it somewhere so others can fetch it, and they need to know how to do that.
I think nomadicness has it’s limits within the current technical constraints that exist.
Paths in ‘ap’ URLs are opaque strings (carry no information), I clarified that in the latest revision of the FEP. They are not tied to HTTP request routing scheme of a specific application.
For example, you can Create a post using software A, and then Update it using software B, installed on a different server, as long as you have the secret key.