SQLServer object_id for indexes?

Each object in the database has its own object_id.

We can find a list of objects and their object_ids either in sys.objects or to view specific types (sys.tables, sys.key_contraints, ...).

Now my question is, do indices have their own object_ids? From what I found, it seems not. If not, why not? It looks like any other object (PK, FK, ...) to me. Even the default constraints have their own object_id.

Thanks for the clarification. This is a question of the "internals", I am not trying to achieve anything, I just want to understand why everything is as it is.