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Re: Relational lattice completeness

From: Jan Hidders <hidders_at_gmail.com>
Date: 30 Mar 2006 14:36:20 -0800
Message-ID: <1143758180.278282.43470@v46g2000cwv.googlegroups.com>

Mikito Harakiri wrote:
> Mikito Harakiri wrote:
> > Jan Hidders wrote:
> > > I'm asking the question for a specific model, not in general as you
> > > did. For example, boolean algebra for boolean value *is* complete.
> >
> > According to Matt all that I have to do to prove incompleteness is to
> > find 2 nonisomorphic relational lattices with the same cardinality...

That is under the assumption you are asking whether you are complete for all models of that cardinality. But here we only have *one* model, namely the (infinite) lattice over all relations as defined by the two operations. So, since there is only one, all the models you are considering are isomorphic.

Sorry for asking such hard questions.

Received on Thu Mar 30 2006 - 16:36:20 CST

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