PROV-ISSUE-466 (must-entities-invalidate): Must all entities invalidate? [prov-dm-constraints]

PROV-ISSUE-466 (must-entities-invalidate): Must all entities invalidate? [prov-dm-constraints]

http://www.w3.org/2011/prov/track/issues/466

Raised by: Stian Soiland-Reyes
On product: prov-dm-constraints

Do we have WG consensus on that all entities must be invalidated,
and all activities must terminate? Seems to talk about the future,
rather than the past.

>From Stian's review http://lists.w3.org/Archives/Public/public-prov-wg/2012Aug/0021.html :


> Inference 7 (entity-generation-invalidation-inference)

> From an entity, we can infer that existence of generation and invalidation events.

This REQUIRES entities to become invalidated (at some point). It is
consistent with entities requiring generation, but it means I get
inferred strange wasInvalidatedBy for real life entities like:

entity(math:pi)
entity(phys:universe)
entity(phys:vacuum)
entity(phys:energy)
entity(concept:existence)
entity(uk:2011census)
entity(uspolitics:resultOfPresidentialElection2012)

When are these destroyed? By what? Is it certain that everything is
destroyed? What about things that are still existing at the time of
provenance being written, with this you are requiring them all to die
- I thought PROV only talked about the past. "We are all going to die"
- but you don't know when or how - so why should the PROV imply
provenance statements about the future?

Received on Monday, 6 August 2012 15:26:56 UTC