Re: more closed-world chatter

On May 10, 9:55 am, Vadim Tropashko <vadimtro_inva..._at_yahoo.com> wrote:
> The generalized Date
> > identity is:
>
> > (A /\ B) \/ (A /\ 00) = A \ (A \ B)
>
> > where /\ is join, \/ is generalized union, and \ is antijoin.
>
> The reason why this formula is fascinating is that setting B=11
> reduces it to
>
> (A /\ 11) \/ (A /\ 00) = A
>
> the "fundamental" decomposition identity (Proposition 1 fromhttp://arxiv.org/abs/cs/0603044).

Writing in small increments... And setting B=00 gives

A /\ 00 = A / A

which is more obvious (and, therefore, less interesting:-) identity. Received on Thu May 10 2007 - 19:10:51 CEST