Friday, October 27, 2017

Constructing a Straggler from an Enumeration of R, {x ∊ R | 0 < x < 1}

Constructing a Straggler from an Enumeration of R, {x R | 0 < x < 1} Using Cantor's Diagonal Method

Theorem 2: Given an enumeration of the set R, {x € R | 0 < x < 1} there exists a real number X, such that X is a straggler.

Proof: Theorem 2 is proved by contradiction. The goal is to prove that there is an X, {X R | 0 < X < 1} that is not part of the enumeration. The proof begins by assuming the opposite, namely, that all elements of R, {x R | 0 < x < 1} can be enumerated. If that assumption is true it must be possible to list the real numbers between 0 and 1 in an infinite table with none missing. An example is depicted graphically below:
 
Real Number

0.2734447…
0.3335894…
0.4664479…
0.5552887…

 Construct a two column table. Column A contains an enumeration of real numbers between 0 and 1. Column B contains a representative value of X. To create X ensure that for the first row in the table the first digit to the right of the decimal in X differs from the first digit to the right of the decimal in the real number column. Keep the procedure going as each row is created, always moving one digit to the right in the real number column as in the illustration (yellow highlight). No matter how long rows are added to the table, X will differ from every real number entry by at least one digit. X then is not in the real number column and never will be no matter how many rows are added to the table. 



Real Number
X


0.2734447…
0.7…
0.3335894…
0.74…
0.4664479…
0.749…
0.5552887…
0.7491…


That contradicts the assertion that all elements of R,  {x R | 0 < x < 1} can be enumerated. The contradiction invalidates the assumption which proves the theorem, X is a straggler.


Thursday, October 26, 2017

Constructing a Straggler from an Enumeration of N, {y ∊ N | 1 ≤ y}



Constructing a Straggler from an Enumeration of N, {y N | 1 ≤ y}
 
Theorem 1: Given an enumeration the set N,  {y N | 1 ≤ y} there exists a natural number Y and Y is a straggler.

Proof:  Theorem 1 is proved by running Program 2 to construct a number Y  that is not part of the enumeration, which contradicts the assumption that all elements of N {y N | 1 ≤ y} can be enumerated with none missing. It is necessary to show that Y will not be included in the enumeration of N for y = 1 where 1 is the set {1},  y = n where n is the set {1, 2, 3, 4, 5, 6} and y = n + 1 where n + 1is the set {1, 2, 3, 4, 5, 6, 7}. We can then use mathematical induction to infer that Y will never appear in the enumeration of N which will prove the theorem.

Constructing the number Y:

Case 1: y = {1}
Output of Program 2

y
Y
1
12
Y = 12

Case 2: y, {1, 2, 3, 4, 5, 6}
Output of Program 2

y
Y
1
12
2
123
3
1234
4
12345
5
123456
6
1234567
Y = 1234567

Case 3: y, {1, 2, 3, 4, 5, 6, 7}
Output of Program 2
 
y
Y
1
12
2
123
3
1234
4
12345
5
123456
6
1234567
7
12345678
Y = 12345678



   





 


This proves the theorem for y = 1, y = n & y = (n + 1) and supports the conclusion that Y will never appear as part of the enumeration no matter how large the enumeration becomes. Thus, given an enumeration of elements from N,  there is an element Y of N for which there is no corresponding  y  in the enumeration. That contradicts the assertion that all elements of N can be enumerated. The contradiction invalidates the assumption which proves the theorem, Y is a straggler.

Wednesday, October 25, 2017

Preliminaries (cont.)



Question 1: Is the set of Natural Numbers N, {y N | 1 ≤ y} demonstrably numerable?

On the surface, it seems perfectly reasonable to assume that the natural numbers are demonstrably numerable. If so, then the natural numbers can be used as a yardstick to compare other infinite sets against in size comparisons.

To list the elements of N one need only devise an algorithm such as:

Let n0 = 1 then n1 = n0 + 1… ni = ni-1 + 1…

and let it iterate forever.

This algorithm can be coded in Visual Basic to generate an endless list of natural numbers:

Module VBModule
Sub Main()

Dim nnum As ULong = 1

For i As ULong = 1 To ∞

     nnum = nnum + 1

Next

End Sub
End Module


If the program is left to run it will generate successive natural numbers indefinitely which implies by mathematical induction that the natural numbers are demonstrably numerable. However, closer inspection reveals that even with infinite iterations of the formula not all natural numbers can be listed, even in theory. This shall be demonstrated in the proof of Theorem 1.

Theorem 1 will be proved by constructing a natural number Y from a listing of the elements of N that will itself never appear in the listing of N, contradicting the assumption that the natural numbers can be enumerated with no exceptions. Modifying the code of the VB program we can generate a natural number from the enumeration of N that will be an element of N but will never appear in the enumeration of N. This is similar to Cantor’s use of the Diagonal Method to show that an enumeration of the real numbers on the (0, 1) interval will permit the construction of a real number on that same interval which will never appear in the enumeration.

Algorithm 1: Let n0 = 1 then n1 = n0 + 1, n2 = n1 + 1… ni = ni-1 + 1…

Program 1: Generate the set of Natural Numbers N, {y N | 1 ≤ y}

Module VBModule
Sub Main()

Dim nnum As ULong = 1

For i As ULong = 1 To ∞

     nnum = nnum + 1

Next

End Sub
End Module


Definition 6: A straggler is a number of the same order that can be constructed from numbers in an enumeration that will never itself appear in the enumeration.

Canon 3: A straggler is a single number. It is not a series of separate numbers as might be inferred from looking at its history as the enumeration of a set grows. As a set is enumerated, time passes and as time passes the straggler changes according to the rules of its construction. For finite sets with a constructible straggler, the straggler in the last row in the enumeration is the straggler that differs from all elements in the enumeration. For infinite sets with a constructible straggler, there is no last row in the enumeration. The straggler is deemed different from all elements in the enumeration if it can be inferred by mathematical induction.

Canon 4: The ability to construct a straggler of the same order from an enumeration of an infinite set implies that the set is not numerable.

Program 2: Construct the straggler Y from the enumeration of N,

Module VBModule
Sub Main()

Dim nnum As ULong = 1
Dim Y As String = "1"
Dim lnum As String = "1"
Dim snum as string = ""

For i As ULong = 1 To ∞

     nnum = nnum + 1
     snum = Cstr(nnum)
     lnum = lnum & snum
     lnum = lnum.Replace(" ", "")

     Y = lnum

Next

End Sub

End Module

Given 1: The set of natural numbers N, {y N | 1 ≤ y}