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GeneralRe: Infinite numbers are strange Pin
StarNamer@work4-Nov-23 14:54
professionalStarNamer@work4-Nov-23 14:54 
GeneralRe: Infinite numbers are strange Pin
Nelek4-Nov-23 20:55
protectorNelek4-Nov-23 20:55 
GeneralRe: Infinite numbers are strange Pin
TNCaver4-Nov-23 9:49
TNCaver4-Nov-23 9:49 
GeneralRe: Infinite numbers are strange Pin
StarNamer@work4-Nov-23 14:51
professionalStarNamer@work4-Nov-23 14:51 
GeneralRe: Infinite numbers are strange Pin
Chris Maunder4-Nov-23 9:55
cofounderChris Maunder4-Nov-23 9:55 
GeneralRe: Infinite numbers are strange Pin
StarNamer@work4-Nov-23 14:52
professionalStarNamer@work4-Nov-23 14:52 
GeneralRe: Infinite numbers are strange Pin
Nelek4-Nov-23 20:57
protectorNelek4-Nov-23 20:57 
GeneralRe: Infinite numbers are strange Pin
StarNamer@work5-Nov-23 4:55
professionalStarNamer@work5-Nov-23 4:55 
Chris Maunder wrote:
There are actually many different "infinities". The numbers 1,2,3...is an infinite set. The set of real numbers between 1 and 2 (eg 1.1, 1.01, 1.001 and on and on) is also infinite, and large than the set of integers. One infinity can be bigger than another infinity. Even though they are both infinite.
Actually, I've never been totally convinced of this, although I'm open to it being proved in some way.

The only way I've ever seen is Cantor's Diagonalization, which says to take a list of all the Real (Rational plus Transcendental, etc) numbers between zero and one then to create a new number by taking the first decimal digit of the first number, second decimal digit of the second number, third of the third, etc. The argument is that this number cannot be on the list, so therefore you can put the infinite number of Reals into correspondence with the Integers so there there is at least a Countable infinity (number of integers) and an Uncountable infinity (number of Reals).

My scepticism comes from the statement about creating the list of Reals. I'd like to use the following pseudo code:
reals = New List<Real>
reals.Add(0.1)
reals.Add(0.5)
reals.Add(pi)
// as many as you want

repeat forever // until list is complete
    for each number r in reals
       x = new real
       for each decimal digit p of r
           digit p of x = not_the_same_as(digit q of r) // function elsewhere
        if x not in reals
            reals.Add(x)
        else
            terminate // countable list of reals is complete
My point is that this procedure *is* Cantor's Diagonalization so if that can find another Real to add, then the list building shouldn't have terminated and, if it can't, then it's not been proved that there are more Reals than Integers. It may be true, but this doesn't prove it.

I feel sure there must be an alternative proof to Cantor's, but I've never found it. Perhaps it relies on maths I've never encountered and would need a degree in Mathematics to understand! (Mine was Physics! Smile | :) )

FYI, I recall I once saw a proof that there are more Transcendental numbers (like pi or e) than Rational numbers (like 1/5, 3/7, etc) but can't recall if it was also based on Cantor's method.

modified 5-Nov-23 13:24pm.

GeneralRe: Infinite numbers are strange Pin
jschell6-Nov-23 11:55
jschell6-Nov-23 11:55 
GeneralRe: Infinite numbers are strange Pin
Daniel Pfeffer4-Nov-23 11:50
professionalDaniel Pfeffer4-Nov-23 11:50 
GeneralRe: Infinite numbers are strange Pin
StarNamer@work4-Nov-23 14:52
professionalStarNamer@work4-Nov-23 14:52 
GeneralRe: Infinite numbers are strange Pin
StarNamer@work5-Nov-23 4:02
professionalStarNamer@work5-Nov-23 4:02 
GeneralRe: Infinite numbers are strange Pin
Kornfeld Eliyahu Peter4-Nov-23 19:59
professionalKornfeld Eliyahu Peter4-Nov-23 19:59 
GeneralRe: Infinite numbers are strange Pin
StarNamer@work5-Nov-23 4:30
professionalStarNamer@work5-Nov-23 4:30 
GeneralRe: Infinite numbers are strange Pin
Daniel Pfeffer5-Nov-23 19:42
professionalDaniel Pfeffer5-Nov-23 19:42 
GeneralRe: Infinite numbers are strange Pin
jschell6-Nov-23 12:02
jschell6-Nov-23 12:02 
GeneralRe: Infinite numbers are strange Pin
Daniel Pfeffer6-Nov-23 15:02
professionalDaniel Pfeffer6-Nov-23 15:02 
GeneralRe: Infinite numbers are strange Pin
jschell7-Nov-23 5:05
jschell7-Nov-23 5:05 
GeneralRe: Infinite numbers are strange Pin
Kornfeld Eliyahu Peter13-Nov-23 22:17
professionalKornfeld Eliyahu Peter13-Nov-23 22:17 
GeneralRe: Infinite numbers are strange Pin
Richard Deeming5-Nov-23 21:38
mveRichard Deeming5-Nov-23 21:38 
GeneralWordle 868 Pin
StarNamer@work3-Nov-23 14:02
professionalStarNamer@work3-Nov-23 14:02 
GeneralRe: Wordle 868 Pin
Amarnath S3-Nov-23 14:17
professionalAmarnath S3-Nov-23 14:17 
GeneralRe: Wordle 868 Pin
Sandeep Mewara3-Nov-23 19:48
mveSandeep Mewara3-Nov-23 19:48 
GeneralRe: Wordle 868 - 2 4 me Pin
pkfox3-Nov-23 21:55
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GeneralRe: Wordle 868 Pin
Cp-Coder4-Nov-23 0:04
Cp-Coder4-Nov-23 0:04 

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