Re: infinity



Virgil said:
> In article <MPG.1d88ece773ad803c98a20c@xxxxxxxxxxxxxxxxxxxxxxxxx>,
> Tony Orlow (aeo6) <aeo6@xxxxxxxxxxx> wrote:
>
> > Virgil said:
> > > In article <MPG.1d879fe6c1c5af7398a1e5@xxxxxxxxxxxxxxxxxxxxxxxxx>,
> > > Tony Orlow (aeo6) <aeo6@xxxxxxxxxxx> wrote:
> > >
> > > > Virgil said:
> > > > > In article <1125629551.621618.60990@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
> > > > > "William Hughes" <wpihughes@xxxxxxxxxxx> wrote:
> > > > >
> > > > > > Tony Orlow (aeo6) wrote:
> > > > >
> > > > > > > The only contradiction arises from your obsession with a last
> > > > > > > element, and conflation of it with finiteness for a set. I do
> > > > > > > not accept that a last element necessarily indicates a finite
> > > > > > > set,
> > > > >
> > > > > There are ordered sets with largest elements that are infinite,
> > > > > such as the closed unit interval, but there are no non-empty
> > > > > ordered sets without a largest element, at least according to the
> > > > > Cantor definition of finiteness.
> > > > >
> > > > > I challenge TO to produce either a set which does not allow any
> > > > > injections into proper subsets that is infinite by TO's definition
> > > > > or to
> > >
> > >
> > > > All whole numbers from 100...000 through 111...111.
> > >
> > > Now PROVE that there is no injection from the set of all those whatever
> > > they are to any proper subset!
> > >
> > > > > produce any set which does allow an injection into a proper subset
> > > > > that is finite by TO's definition.
> > > > >
> > > > > Absent TO's successful production of at least one of these two
> > > > > types of examples, we are free to impose the Cantor criterion for
> > > > > finiteness/infiniteness of sets on all his postings.
> > > > >
> > > > > The Cantor criteria are: A set is finite if and only if there do
> > > > > not exist any injections from that set to any proper subset; a set
> > > > > is infinite if and only if there exists at least one injection from
> > > > > that set to some proper subset.
> > > > >
> > > > > Note that according to these criteria, a non-empty ordered set
> > > > > without a maximum (or minimum) member, such as the set of (finite)
> > > > > naturals, is necessarily infinite.
> > >
> > > > Yes, Cantor-infinite, as you say, but not infinite by other thinking.
> > >
> > > Cantor-infinite is the only infinite until we have a workable
> > > alternative. So far none of TO's attempts have been workable
> > > > >
> > > > > > > therefore I see no contradiction between the set of finite
> > > > > > > naturals being finite and not having a last element.
> > > > >
> > > > > Then TO must have in mind some some definition of finiteness versus
> > > > > infiniteness of sets incompatible with Cantor's, and should
> > > > > immediately provide that definition to us so that we can understand
> > > > > what he is talking about.
> > >
> > > > The rules of finiteness that you seem to be ignoring are that a+b,
> > > > a*b and a^b are all finite for finite a and b. Do you disagree with
> > > > that statement?
> > >
> > > If a and b are any members of any ring, including the ring of integers
> > > or the field of reals, a+b and a*b will be members of that same ring,
> > > but a^b need not be.
> > a^b=a*a*a*a..., so why do you say a*b will be a member of the same ring, but
> > a*a*a... is not?
>
>
> I did not say that, what I said was that a*b need not be a member of the
> ring.
>
> In the ring of integers, 2^(-2) is not a member of that ring.
>
> In the ring of rationals, (2)^(1/2) is not a member of that ring.
>
> In the ring of reals, (-1)^(1/2) is not a member of that ring.
Okay, gotcha. Thanks for the examples. However, this doesn't affect the fact
that for finite positive non-zero whole numbers a and b, a^b is a finite
positive non-zero whole number, and that a^b can only be infinite if either a
or b is infinite. Do you honestly disagree with this fact?
> > >
> > > Since "standard" rings are of finite elements (their compactifications
> > > are not, in general, rings), the sum or product of two members will be
> > > as finite as their summands or factors.
> > Are you saying a^b can be infinite with finite a and b?
>
> I am saying that a^b need not be defined at all within the ring in
> question.
The "ring" of positive finite non-zero whole numbers? Even if that is not a
ring, that is the set we are discussing, so this whole point seems rather
impertinent.
>
> Learn some mathematics before pontificating about it.
Object only where your objection is valid, and stop dragging in irrelevant
information just to confuse.
>

--
Smiles,

Tony
.



Relevant Pages

  • Re: JSH: More on problem, algebraic integers
    ... I knew there was a reason I had the second condition, ... >> The second condition is that for every member m there exists ... that distinguishes your "object ring" from the ring of AI's. ... condition was not satisfactory before, ...
    (sci.math)
  • Re: Object ring: corrected definition
    ... > The object ring is a commutative ring that includes all numbers such ... where no non-unit member is a factor of any two integers that ... and where given a member x there must exist a nonzero ...
    (sci.math)
  • Re: Pioneering Gauss, properties of integrality
    ... > where the grouping had 3 key characteristics shared with the ring of ... For any member x there must exist a nonzero member y such that xy ... > They defined algebraic integers to be the roots of monic polynomials ... > the 3 key characteristics I mentioned above. ...
    (sci.math)
  • Re: Object ring: corrected definition
    ... >> The object ring is a commutative ring that includes all numbers such ... >> are coprime in the ring of integers, and where given a member x there ... >> must exist a nonzero member y such that xy is an integer. ... Is this the fifth or sixth adjustment? ...
    (sci.math)
  • Re: Object ring, new definition
    ... where given a member x there must exist a member y such that ... There still remains the problenm of instantiating such a ring, R, i.e., ... maximality of some sort. ...
    (sci.math)