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Topic: Skepticism, mysticism, Jewish mathematics
Replies: 115   Last Post: Aug 7, 2006 1:30 AM

 Messages: [ Previous | Next ]
 Rupert Posts: 3,810 Registered: 12/6/04
Re: Skepticism, mysticism, Jewish mathematics
Posted: Aug 4, 2006 3:41 AM

R. Srinivasan wrote:
> Rupert wrote:
> > R. Srinivasan wrote:
> > > Rupert wrote:
> > > > R. Srinivasan wrote:
> > > > > Barb Knox wrote:
> > > > > >
> > > > > > Consider that calculus too started out as a half-baked theory laden with
> > > > > > paradoxes, and that one of the great mathematical achievements was to
> > > > > > put it on a rigourous footing. And indeed, set theory was one of the
> > > > > > important tools in that enterprise.

> > > > >
> > > > > The presently accepted foundations of the calculus still does not
> > > > > resolve Zeno's paradoxes.

> > > >
> > > > Why not? What's the paradox?

> > >
> > > The paradox can be stated in two ways. Consider the example of Achilles
> > > chasing the tortoise along a straight line at a constant velocity
> > > higher than that of the tortoise's (constant velocity). The paradox is
> > > that Achilles has to "complete" infinitely many opertaions to catch up
> > > with the torotoise -- from the starting point he sees the tortoise at a
> > > particular location ahead, and he first has to reach that location.
> > > When he reaches, he sees the toroise ahead at another location, and
> > > Achilles has to reach there. And ad infinitum. The Greeks thought that
> > > this was a paradox presumably because they viewed infinity as
> > > "potential", i.e., the infinitely many operations required to reach the
> > > torotoise cannot never be completed in finite time.
> > >

> > > >From the modern point of view the paradox can be stated as follows.
> > > How can infinitely many finite, non-zero, non-inifnitesimal intervals
> > > of reals sum to a finite interval (why isn't the sum infinite)? I..e,
> > > suppose starting from location zero, Achilles first reaches 1/2, then
> > > 3/4, then 7/8,...... Then Achilles covers the distance
> > > 1/2+1/4+1/8.....=1, where he catches up with the tortoise. The paradox
> > > is -- why isn't the sum infinite, given that there are infinitely many
> > > finite, non-zero and non-infinitesimal intervals being summed (assume
> > > we are using some standard version of real analysis).
> > >

> >
> > Well, it just isn't. I don't see any reason why it should be. You
> > haven't shown a contradiction in standard real analysis.

>
>
> That is true. The same can be said of the Banach-Tarski paradox or many
> of the other paradoxes of classical measure theory. But these are
> paradoxes nevertheless, and highly counter-intuitive.
>
> Regards, RS

Well, they may be counter-intuitive for some people. I agree the
Banach-Tarski paradox is a rather surprising result. But the fact that
the sum of an infinite series of positive numbers can be finite I don't
find counterintuitive at all, myself. Do you really claim to have a
formulation of analysis where this result is avoided? Can you tell me
what it is?

Date Subject Author
7/25/06 David Petry
7/25/06 fishfry
7/25/06 Dr. David Kirkby
7/25/06 Dr. David Kirkby
7/25/06 lloyd
7/25/06 Doug Schwarz
7/25/06 Virgil
7/26/06 Mike Kelly
7/26/06 David Petry
7/26/06 Gene Ward Smith
7/26/06 Brian Quincy Hutchings
7/26/06 dkfjdklj@yahoo.com
7/26/06 herbzet
7/26/06 David Petry
7/28/06 herbzet
7/26/06 herbzet
7/26/06 lloyd
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7/26/06 dkfjdklj@yahoo.com
7/26/06 herbzet
7/26/06 Gene Ward Smith
7/26/06 Gerry Myerson
7/26/06 David Petry
7/26/06 Randy Poe
7/26/06 mensanator
7/27/06 Richard Herring
7/27/06 mensanator
7/27/06 Richard Herring
7/26/06 Gene Ward Smith
7/26/06 David Petry
7/26/06 Patricia Shanahan
7/26/06 Gene Ward Smith
7/28/06 herbzet
7/26/06 Dr. David Kirkby
7/26/06 Randy Poe
7/27/06 Rotwang
7/28/06 herbzet
7/30/06 Han de Bruijn
7/30/06 Barb Knox
7/30/06 zr
7/30/06 Virgil
7/30/06 Gene Ward Smith
7/30/06 zr
8/1/06 Virgil
7/30/06 T.H. Ray
7/31/06 Brian Quincy Hutchings
7/31/06 T.H. Ray
8/1/06 Brian Quincy Hutchings
8/1/06 David R Tribble
7/30/06 Gene Ward Smith
7/30/06 Ioannis
7/30/06 Dr. David Kirkby
7/30/06 zr
7/30/06 Dave Rusin
8/1/06 David Bernier
8/1/06 David R Tribble
8/2/06 Ioannis
7/31/06 Han de Bruijn
8/2/06 R. Srinivasan
8/3/06 Rupert
8/4/06 R. Srinivasan
8/4/06 R. Srinivasan
8/4/06 Rupert
8/4/06 R. Srinivasan
8/4/06 Rupert
8/4/06 R. Srinivasan
8/4/06 Mike Kelly
8/4/06 R. Srinivasan
8/4/06 Mike Kelly
8/4/06 R. Srinivasan
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8/4/06 Mike Kelly
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8/7/06 R. Srinivasan
8/4/06 Mike Kelly
8/5/06 R. Srinivasan
7/28/06 herbzet
7/28/06 Gene Ward Smith
7/28/06 herbzet
7/28/06 mensanator
7/28/06 herbzet
7/27/06 T.H. Ray
7/28/06 herbzet
7/29/06 David Petry
7/30/06 herbzet@cox.net
8/4/06 Jack Markan
8/4/06 T.H. Ray
7/26/06 David R Tribble
7/26/06 Gene Ward Smith
7/26/06 T.H. Ray
7/26/06 toni.lassila@gmail.com
7/26/06 Bennett Standeven
7/26/06 Brian Quincy Hutchings
7/27/06 Rotwang
7/27/06 Craig Feinstein
7/27/06 Toni Lassila
7/27/06 Craig Feinstein
7/27/06 Brian Quincy Hutchings
7/27/06 Rupert
7/28/06 zr
7/28/06 herbzet
7/28/06 T.H. Ray
7/29/06 zr
7/29/06 Virgil
7/29/06 zr
7/29/06 Virgil
7/30/06 herbzet@cox.net
7/30/06 T.H. Ray
7/30/06 LauLuna
7/30/06 LauLuna