@NEETzsche @lain @Moon so you intend on being wrong on purpose?

Let me quote the spec you love so much once again:
https://www.w3.org/TR/activitystreams-vocabulary/#dfn-url
>Identifies one or more links to representations of the object

Let's analyze this statement.

What is an object? It's a concrete thing, i.e. this specific omori cofe mug on my table, my computer mouse with serial number GB79G0158603A, my cellphone. It is a unique and specific thing, not a "class" of thing, object refers to an instance, object is not just any mug, any computer mouse, or a concept of a cellphone. In our case it's a document or what typical users would call "a post"

What is a representation? Essentially it's a projection or interpretation of the object. A digital photo of my mouse is a representation. A drawing of my cofe mug is a representation. A sheet of paper describing IMEI and technical specs of my phone is a representation. There is intentional one-way relationship between an object and representation. If i show you a picture of my computer mouse and say "that's your computer mouse" or "that's my keyboard" it would be factually incorrect, it's incorrect interpretation that representation is about different object.

In real world there are no clear definitions and relations, but in a computer database there are. You could ask database "what is this representation all about" and it should give you one concrete answer - "this is a representation of object X" however if you have several objects with same representation database would be confused whether it's object X or object Y or possibly object Z, therefore breaking this one-way relationship, we end up having a representation that can represent multiple object. A document spec with IMEI of my phone now can be representative of my phone or your phone, picture of my mouse can be representative of my mouse or my keyboard.

In our case the so-called "Pleroma Audio" is an object, and url is its representation. There is no mechanism to deduplicate and/or verify the url, or just update the "Pleroma Audio" document, so when you query https://www.youtube.com/watch?v=BJCEArh2E1s you'll get possibly half a dozen documents all titled "iteachvader - Getaway Submarine (Clean)" and possibly different spellings, translations and capitalization, even though there's still only one canonical YouTube link. From point of view of database, we have same representation point to several (possibly idential) copies of same object. And in case of url pointing towards a funkwhale audio we'll have several copies in our format as well as as one copy in funkwhale format, so which one is the "real" or "canonical" one?

Otherwise what is the reason or the point of having one representation point towards multiple objects?