Four Color Theorem and beyond!

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

Four Color Theorem and beyond!

Steve Smith
In the deafening silence of Doug's withdrawal to his private vacation cottage, I submit this for your "FRIAMic Consideration", as it were.

This colleague of mine has a penchant for his own level of weight in his postings...  he might put the most obscure and obtuse of us to shame. His postings of this nature are, however, always thorough, footnoted, and referenced.   He also publishes a weekly "kitchen science" column in the Espanola Rio Grande Sun.   And no, he is not "little".  And he lives halfway between myself and Doug (geographically).

My own commentary *follows* the posting.


----- Original Message -----
To: X
Sent: Friday, April 26, 2013 8:04 AM
Subject: Re: "The Notorious Four-Color Problem"
 
Jeremy Martin's KU mini-course (see thread below) on the Four-Color Theorem (FCT, "Every planar map is four colorable", [1]) promises to be a spectacle.
 
It's hard to overestimate the importance of the FCT, and on any dispassionate reckoning, it would have to ranked among the 100 most important theorems of mathematics. 
 
A "color", in the sense of the FCT, is any nominal distinguishable property; "red, green, blue, and yellow" work as well as any. 
 
Given this meaning of "color", the FCT, at the heart of which is the notion of  "four-foldness",  is much more than a cartographic curiosity.  To sketch a few: 
 
 
    1.  The Prague School of linguistics maintains that meaning in all natural languages can be represented in a system that makes no more than *four* kinds of distinctions (applied  indefinitely/recursively) between "adjacent" meanings ([2], [3]).  It turns out that these meaning-relations can be represented in a planar map.  We can thus think of the FCT as a representation of the structure of the meaning of anything that can be expressed in a natural language. 
 
 
    2.  The dances of the indigenous peoples of the upper Rio Grande (e.g., the Corn Dance, the Deer Dance) turn out, one and all, to be generatable from a set of exactly four fundamental dance moves.  The belief systems of these cultures places fundamental emphasis on the "four-foldness" of the world.  In light of (1) and the FCT, these dances, whatever their  nominal semantics, may be "essays" on the meaning of 'meaning' ([8]).
 
    3.  Adherents of the logicist program in mathematics ([5], esp. Chaps. II-III) hold that all of mathematics *could* be expressed in set theory (together with a "logic" and a raft of "mere" definitions).    In its most rigorous form, set theory presumes a four-fold set of distinctions ("is a class", "is a set" (a restriction of a class), "is a member of a class", and "is a member of a set" ([9]).  This view of mathematics is thus equivalent to a set-theoretic version of the FCT.
 
    4.    The structures of the derivations (proofs) all theorems in mathematics can be represented in a planar map. The FCT guarantees, in effect, that no more than four kinds of distinctions need to be made between adjacent "steps" in the totality of all derivations in mathematics.
 
    5.  The Book of Kells ([4]), a medieval Irish religious manuscript, is densely illuminated with images of Celtic knots.  Most if not all of the knots in the Book of Kells are, or are composable from, the simplest Celtic knot, the trefoil knot, which the authors of the Book of Kells likely regarded as a symbol of the the trinity -- the irreducible three-in-one. The structure of the trefoil knot is representable in a planar map, and therefore, by the FCT, the structure of the trefoil knot is  four-colorable.  One could (though in practice no one would) take a (set-theoretic) description of the trefoil knot as something to be "unpacked" by more derivative mathematics, and in the course of that investigation, be driven to the FCT.
 
    6.  According to modern genetic theory, a set of four nucleic acids (A, C, T, G) is *sufficient* to encode the genetics of all terrestrial life ([10]).  But as astonishing is that *exactly* four distinct building blocks (regardless of their specific chemistry) are also *necessary* to optimize the integrity of  the transmission of information ([7]) in noisy environments over long times (e.g., across mutiple generations; [6]). 
 
 
Jack
 
---
 
[1]  Appel K and Haken W.  Every Planar Map is Four Colorable.  American Mathematical Society.  1989.  As Martin notes, the original proof was completed in 1976.  Minor corrections to the proof were added over the the following decade.
 
[2]  Jakobson R and Halle M.  Fundamentals of Language.  Mouton.  1971.
 
[3]  van Schooneveld CH.  Semantic Transmutations: Prolegomena to a Calculus of Meaning: The Cardinal Semantic Structure of Prepositions, Cases and Paratactic Conjunctions in Contemporary Standard Russian.  Physsardt, Bloomington IN.  1978.
 
[4]  Book of Kells.  MS A. I. (58). Trinity College Library, Dublin.  Circa 800. 
 
[5]  Körner S.  The Philosophy of Mathematics: An Introductory Essay.  1968.  Dover reprint, 1986.
 
[6]   Petoukhov SV.  The rules of degeneracy and segregations in genetic codes. The chronocyclic conception and parallels with Mendel’s laws. Advances in Bioinformatics and its Applications, Series in Mathematical Biology and Medicine  8 (2005), 512-532.  
 
[7]  Cover TM and Thomas JA.  Elements of Information Theory.  Wiley.  1991.
 
[8]  Putnam H.  The meaning of 'meaning'.  In H Putnam.  Mind, Language, and Reality.  Cambridge.  1975. pp. 215-271.
 
[9]  Fraenkel A and Bar-Hillel Y.  Foundations of Set Theory.  North Hollnad.  1958.
 
[10]  Hartwell L, Hood L, Goldberg M, Reynolds A, and Silver L.  Genetics: From Genes to Genomes.  McGraw-Hill.  2010.

 

----- Original Message -----
From: Z
To: Y
Sent: Thursday, April 25, 2013 7:52 PM
Subject: "The Notorious Four-Color Problem"

Apropos of our discussion at Saralyn’s loft on the evening of April 17, in which I brought up the Four-Color Problem and Jack gave a cogent description of it for the layman, I discovered that one of the classes being taught at the Mini College this June covers the same topic.  Here is the description from the Mini College schedule (https://kuecprd.ku.edu/~clas/minicoll/schedule/index.shtml), which does a pretty good job of explaining the problem and hints at the method of solving it:
 
 
The Notorious Four-Color Problem
Jeremy Martin, Mathematics

How many colors are required to color a map so that no two adjacent regions (say, Kansas and Missouri) are given the same color? It turns out that every map can be colored with at most four colors, a fact suspected to be true since 1852, but not confirmed until 1976 (with the aid of intensive computation, an unprecedented approach to research at the time). In the century-long attempt to solve the map-coloring problem, mathematicians have developed theories of unexpected power and beauty: for example, problems about optimal routing and scheduling (and even Sudoku puzzles!) can be expressed as graph coloring problems. This course will explore both the history and the mathematics of the four-color theorem, including its practical applications, the many failed attempts to solve the problem, the debate over the validity of computer-assisted proofs, and the theoretical research for which mathematician Maria Chudnovsky was recently awarded a MacArthur "genius" grant.


 
Jack K. Horner
P.O. Box 266
Los Alamos, NM  87544
Voice: 505-455-0381
Fax: 505-455-0382
email: [hidden email]


SAS commentary
I have not taken the time to follow all of Jack's references and this expose' verges on numerological argumentation, at least half of the bullet points below are convincing to me on their own merits.

The position is that "4" is a certain kind of magic number in a topological sense, relevant to some fundamental things like Cartography, Language, Aboriginal Cosmology, Mathematics, Genetics, and most oblique... the Celtic Knot.

Reminds me of the anthropic posit-ion that we live in 3 (perceptible) spatial dimensions because it is the lowest number of dimensions where all graphs can be embedded without edge-crossings.  Can't remember the source of this....
 



============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
to unsubscribe http://redfish.com/mailman/listinfo/friam_redfish.com
Reply | Threaded
Open this post in threaded view
|

Re: Four Color Theorem and beyond!

glen ep ropella

I agree with you about the "numerological" or anthropomorphic feel of
this attempt to unify disparate subjects with a common pattern.  But I
can only speak to the bias I see in example 3.  At this point, I'm sure
I sound like a broken record.  So, I'll merely raise the point again and
leave it be unless others chime in.

The discretization into 4 types (set, class, set member, class member)
is violated in lots of mathematics as it's practiced, namely in
impredicative definitions (sets defined by a quantification over the set
being defined).  This is indirectly related to the openness of practical
math raised by Feferman and the demonstrations of the practical utility
of formal systems that are both complete and consistent (i.e. "simple"
enough to escape the GIT, but complex enough for engineers to use to
good effect).

Aczel helped to formulate this rigorously and demonstrated a
foundational math where a set can be a member of itself, which means the
magic number would not be 4, but 3 (or perhaps 2).  So, the bias toward
4 is situational, I think.

That does NOT mean the idea isn't interesting, though.

On 04/27/2013 08:28 AM, Steve Smith wrote:

> SAS commentary
> I have not taken the time to follow all of Jack's references and this
> expose' verges on numerological argumentation, at least half of the
> bullet points below are convincing to me on their own merits.
>
> The position is that "4" is a certain kind of magic number in a
> topological sense, relevant to some fundamental things like Cartography,
> Language, Aboriginal Cosmology, Mathematics, Genetics, and most
> oblique... the Celtic Knot.
>
> Reminds me of the anthropic posit-ion that we live in 3 (perceptible)
> spatial dimensions because it is the lowest number of dimensions where
> all graphs can be embedded without edge-crossings.  Can't remember the
> source of this....


> ------------------------------------------------------------------------
>
> ----- Original Message -----
> *From:* Jack K. Horner <mailto:[hidden email]>
> *To:* X
> *Sent:* Friday, April 26, 2013 8:04 AM
> *Subject:* Re: "The Notorious Four-Color Problem"
> Jeremy Martin's KU mini-course (see thread below) on the Four-Color
> Theorem (FCT, "Every planar map is four colorable", [1]) promises to be
> a spectacle.
> It's hard to overestimate the importance of the FCT, and on any
> dispassionate reckoning, it would have to ranked among the 100 most
> important theorems of mathematics.
> A "color", in the sense of the FCT, is any nominal distinguishable
> property; "red, green, blue, and yellow" work as well as any.
> Given this meaning of "color", the FCT, at the heart of which is the
> notion of  "four-foldness",  is much more than a cartographic
> curiosity.  To sketch a few:
>[...]
>     3.  Adherents of the logicist program in mathematics ([5], esp.
> Chaps. II-III) hold that all of mathematics *could* be expressed in set
> theory (together with a "logic" and a raft of "mere" definitions).    In
> its most rigorous form, set theory presumes a four-fold set of
> distinctions ("is a class", "is a set" (a restriction of a class), "is a
> member of a class", and "is a member of a set" ([9]).  This view of
> mathematics is thus equivalent to a set-theoretic version of the FCT.
> [...]
> [5]  Körner S.  The Philosophy of Mathematics: An Introductory Essay.
> 1968.  Dover reprint, 1986.
> [9]  Fraenkel A and Bar-Hillel Y.  Foundations of Set Theory.  North
> Hollnad.  1958.

>
>
> Jack K. Horner
> P.O. Box 266
> Los Alamos, NM  87544
> Voice: 505-455-0381
> Fax: 505-455-0382
> email: [hidden email] <mailto:[hidden email]>
> ------------------------------------------------------------------------
>

--
glen e. p. ropella  http://tempusdictum.com  971-255-2847

============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
to unsubscribe http://redfish.com/mailman/listinfo/friam_redfish.com