Re: Unbounded intervals
P1788
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John Pryce
From: John Pryce <smajdp1@xxxxxxxx>
Date: 8 May 2012 20:07:34 GMT+01:00
To: stds-1788 <stds-1788@xxxxxxxxxxxxxxxxx>
Subject: Re: Unbounded intervals
Nate and all
I have at last had time to read most of this discussion, or counterpoint as Baker aptly called it. If Nate puts a solid basis on the OVR concept it will in the end come down to correct choice of quantifiers: e.g., which logical assertions are to be true for *some* member of his family of intervals, as opposed to for *all* members.
As a starter, Nate can you give me your definition of A \subseteq B for intervals A and B? Ideally phrased entirely in terms of the set theory primitive \in, but I would accept a definition that uses \subseteq for plain intervals (i.e. ordinary sets).
I'm particularly interested in the case where A = [a,+OVR] and B = [b,+OVR] for real a and b, but if you have formulae for all combinations, that would interest me too.
John Pryce