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Motion P1788/M003.01_Set_of_reals NO




I agree "we should think of Infinity as a set of values itself rather than a single value, that is, something representing many possible values from which no particular value can be determined."

My wording on my vote was imprecise.  "Infinity" may mean the mathematical concept which as Scott says is not a single value, or it may mean the bit pattern which is a single value of a variable or expession and which represents the concept which is an infinite set of infinite values.  In IEEE 754 it also represents an infinite set of finite overflow values, greater than the maximum representable finite value but less than infinity.  In my job the second meaning is more common.  Generally the context makes it clear, but in this case it did not.  I apologize for any confusion and thank Scott for the clarification.

- Ian McIntosh          Toronto IBM Lab   8200 Warden   D2-445

----- Forwarded by Ian McIntosh/Toronto/IBM on 20/04/2009 08:17 PM -----
Scott Ferson <scott@xxxxxxxxx>

20/04/2009 07:27 PM
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Motion P1788/M003.01_Set_of_reals NO





NO

I have two problems with the definitions.  An interval should be an abstraction.  A set of reals is one possible incarnation, but so is a set a probability distributions all of whose supports are constrained by the endpoints.  It doesn't seem like good mathematics to be unnecessarily specific.

I agree with most of Ian Macintosh's views, except to say that, from the perspective of non-standard analysis, it seems that we should think of Infinity as a set of values itself rather than a single value, that is, something representing many possible values from which no particular value can be determinied.  This goes for infinitesimals too, such as 1/Infinity, which are useful in defining open and partially open intervals.

Scott Ferson