@reiver@mastodon.social1/
You could have a post on one server host attribute and account on another server host as its author.
All you have to do is set the "attributedTo" field appropriately.
https://www.w3.org/TR/activitystreams-vocabulary/#dfn-attributedto
For example....
2/
For example, at:
http;//example·com/object/123
You might have the activity-JSON (application/activity+json):
{
....
"attributedTo": "https;//mastodon·social/users/reiver",
...
}
I.e., a Note or Article or whatever is saying that the author is NOT an actor on the same server host (example·com), but an actor over on the server host mastodon·social.
...
3/
Now, this would probably break like counts, share counts, a replies to some degree.
But, if you didn't care about that, I think it should work.
...
4/
This needs some testing to see what extant Fediverse software actually does.
For example — with the extant Fediverse software —
Does the avatar image, the (actor) name, etc show up with the post?
Does the post show up?
Etc?
@reiver This'll likely fail validation in mature server implementations because, given the way you describe it, it lacks a mechanism to prevent adversarial attribution. Meaning I could use my own server to attribute abusive posts to you without your knowledge. Signature-based object integrity proofs could help with this.
See also: https://codeberg.org/fediverse/fep/src/branch/main/fep/fe34/fep-fe34.md
