Linking to a post from any instance

I'm just wondering if there's any strategy to link to a post in an instance agnostic kind of way.

Take for example this post which originates in !lemmy@lemmy.ml.

If someone sent me that link but I did not have a lemmy.ml account, then I can read it but not participate.

If I have an account at lemmy.world then it's not trivial to find that post on that instance. I can't just edit the url because the post ID is not the same. I'd have to navigate to lemmy.world/c/lemmy@lemmy.ml and find the post from that feed. This might be possible for recent posts but becomes very difficult with any posts even a little stale.

My understanding of "how lemmy works" is very naive, but I assume it's not possible to generate UUIDs for posts. That being the case you'd need separate lookup servers that maintain lists of urls for posts and can translate between them.