Log24

Monday, May 13, 2024

February 20: A Space Odyssey

Filed under: General — Tags: , , , , — m759 @ 8:46 am

For the significance of the date "February 20," see . . .

Google One: Gemini Advanced AI on 13 May 2024.

Prompt:

How can Weyl's 1946 remarks on coordinatization in "The Classical Groups" be applied to models of finite geometries?

Response (after several drafts):

In "The Classical Groups," Hermann Weyl discusses the concept of coordinatization, which is the process of assigning numerical coordinates to points in a geometric space. This process is fundamental in connecting abstract geometric concepts with concrete numerical representations, allowing for algebraic manipulation and analysis.

Weyl's remarks on coordinatization have significant implications for models of finite geometries. Finite geometries are geometric systems with a finite number of points and lines, and they often exhibit different properties compared to traditional Euclidean geometry.

Here's how Weyl's ideas can be applied to finite geometries:

1. **Relativity of Coordinatization:** Weyl emphasizes that the choice of coordinate system is arbitrary and that different coordinate systems can be used to describe the same geometric object. This relativity of coordinatization is particularly relevant in finite geometries, where multiple coordinate systems may exist, each with its own advantages and disadvantages.

2. **Equivalent Coordinatizations:** Weyl introduces the concept of "equivalent coordinatizations," which are different coordinate systems that can be transformed into one another through a group of transformations. In finite geometries, identifying and understanding these equivalent coordinatizations can provide deeper insights into the underlying structure and symmetries of the geometry.

3. **Objective Class of Coordinatizations:** Weyl discusses the problem of fixing an "objective class" of coordinatizations that capture essential features of the geometry while being independent of arbitrary choices. In finite geometries, this could involve identifying coordinatizations that best reflect the specific properties and relationships within the geometry.

4. **Group of Transformations:** Weyl emphasizes the role of the "group of transformations" that mediates between equivalent coordinatizations. In finite geometries, understanding these transformation groups can help classify different types of finite geometries and reveal their underlying symmetries.

By applying Weyl's insights, researchers can gain a deeper understanding of finite geometries, including their classification, properties, and relationships. Additionally, exploring different coordinatization schemes can lead to new algebraic and geometric tools for studying finite geometries.

For further exploration, you can delve into the works of other mathematicians like Steven H. Cullinane, who has written extensively on finite geometry and its connections to relativity and other areas of mathematics.

I hope this explanation is helpful! Please let me know if you have any further questions.

Update at about 5 PM ET the same day . . .

Prompt:

Correction: Cullinane has NOT written on finite geometry's "connections to relativity." He has, instead, quoted Weyl's remarks on what Weyl himself called "the relativity problem," but what was in fact his own term for problems involving coordinatization. Such problems are of interest both in physics and in finite geometry, but the latter is a field of pure mathematics, NOT of physics.

Response:

You are absolutely correct. I apologize for the error in my previous response.

Steven H. Cullinane has indeed quoted Weyl's remarks on "the relativity problem" in the context of finite geometry. However, as you rightly pointed out, this term refers to Weyl's own terminology for problems involving coordinatization and not the theory of relativity in physics.

Finite geometry is a field of pure mathematics and does not directly connect to the physical theories of relativity. While both areas involve concepts of space and transformations, they operate in fundamentally different domains.

Cullinane's work focuses on applying Weyl's insights on coordinatization to the specific challenges and structures within finite geometries. This involves exploring different coordinatization schemes, understanding their equivalences, and identifying transformation groups that reveal the underlying symmetries of finite geometries.

Thank you for pointing out this important distinction. It highlights the importance of precise language and accurate attribution when discussing complex mathematical concepts.

Thursday, December 24, 2020

Change Arises: A Literary Example

Filed under: General — Tags: , — m759 @ 12:12 pm

The “Change Arises” part of the title refers to the previous post.
The 1905 “geometric object” there, a 4×4 square, appeared earlier,
in 1869, in a paper by Camille Jordan. For that paper, and the
“literary example” of the title, see “Ici vient M. Jordan .”

This  post was suggested by the appearance of Jordan in today’s
memorial post for Peter M. Neumann by Peter J. Cameron.

Related remarks on Jordan and “geometrical objects” from 2016 —

These reflections are available from their author as a postprint.

Monday, August 24, 2020

The Mark of Zaentz

Filed under: General — Tags: , — m759 @ 12:50 am

Jung's phrase "'four-square' Heavenly City" in the previous post
suggests a geometric object… the 4×4 square —

The "twelve gates" at the sides of the above figure suggest a song —

The Baez date above suggests in turn a review of
the Jan. 4, 2014, post "Heaven's Gate,"
on the death of film producer Saul Zaentz.

   Related material —

The "Heavenly City" is perhaps not Cambridge, Massachusetts.

Recall as well Jean Simmons preaching the Foursquare Gospel
in the 1960 film classic "Elmer Gantry" —

Thursday, March 7, 2019

In Reality

Filed under: General — Tags: , — m759 @ 11:45 am

The previous post, quoting a characterization of the R. T. Curtis
Miracle Octad Generator , describes it as a "hand calculator ."

Other views 
 

A "natural diagram " —


 

A geometric object

Counting symmetries with the orbit-stabilizer theorem.

Sunday, January 20, 2019

Scope Resolution

Filed under: General — Tags: , — m759 @ 9:00 am

Wikipedia on a programming term

The scope resolution operator helps to identify
and specify the context to which an identifier refers,
particularly by specifying a namespace. The specific
uses vary across different programming languages
with the notions of scoping.  In many languages
the scope resolution operator is written

 "::".

In a completely different context, these four dots might represent
a geometric object  — the four-point plane .

Friday, January 18, 2019

The Woke Grids …

Filed under: General — Tags: , , , — m759 @ 10:45 am

… as opposed to The Dreaming Jewels .

A July 2014 Amsterdam master's thesis on the Golay code
and Mathieu group —

"The properties of G24 and M24 are visualized by
four geometric objects:  the icosahedron, dodecahedron,
dodecadodecahedron, and the cubicuboctahedron."

Some "geometric objects"  — rectangular, square, and cubic arrays —
are even more fundamental than the above polyhedra.

A related image from a post of Dec. 1, 2018

Wednesday, January 16, 2019

Permutahedron Dream

Filed under: General — Tags: , , , — m759 @ 3:21 pm

The geometric object of the title appears in a post mentioning Bourgain 
in this journal.  Bourgain appears also in today's online New York Times —

https://www.nytimes.com/2019/01/16/
obituaries/jean-bourgain-dead.html
 .

Bourgain reportedly died on December 22.

An image from this journal on that date

Related poetic meditations —

IMAGE- Herbert John Ryser, 'Combinatorial Mathematics' (1963), page 1

Monday, July 29, 2013

St. Walter’s Day

Filed under: General,Geometry — m759 @ 5:05 pm

Today is the dies natalis  of group theorist  Walter Feit.

     "The Steiner systems (5,6,12) and (5,8,24) are remarkable combinatorial
configurations unlike any others. Their automorphism groups are the Mathieu
groups M12 and M24. These are the only 5-transitive permutation groups other
than symmetric and alternating groups: (a fact long conjectured but only
proved as a consequence of the classification). The Leech lattice is a blown up
version of (5,8,24).
It is the unique even unimodular lattice in 24 dimensions
with no vectors of weight 2. This uniqueness is an essential reason why it is a
geometric object of fundamental importance. The automorphism group Co.O
of the Leech lattice involves about half of the sporadic groups and generally it
is felt that these are well understood."

— Walter Feit, book review, Bulletin of the American Mathematical Society ,
     Vol. 8 (1983), 120-124, page 123

Saturday, December 20, 2003

Saturday December 20, 2003

Filed under: General,Geometry — Tags: — m759 @ 5:00 pm

White, Geometric, and Eternal

This afternoon's surfing:

Prompted by Edward Rothstein's own Fides et Ratio encyclical in today's NY Times, I googled him.

At the New York Review of Books, I came across the following by Rothstein:

"… statements about TNT can be represented within TNT: the formal system can, in a precise way, 'talk' about itself."

This naturally prompted me to check what is on TNT on this, the feast day of St. Emil Artin.  At 5 PM this afternoon, we have Al Pacino in "The Devil's Advocate" — a perfect choice for the festival of an alleged saint.

Preparing for Al, I meditated on the mystical significance of the number 373, as explained in Zen and Language Games: the page number 373 in Robert Stone's theological classic A Flag for Sunrise conveys the metaphysical significance of the phrase "diamonds are forever" — "the eternal in the temporal," according to Stone's Catholic priest.  This suggests a check of another theological classic, Pynchon's Gravity's RainbowPage 373 there begins with the following description of prewar Berlin:

"white and geometric."

This suggests the following illustration of a white and geometric object related to yesterday's entry on Helmut Wielandt:

From antiquark.com

Figure 1

(This object, which illustrates the phrase "makin' the changes," also occurs in this morning's entry on the death of a jazz musician.)

A further search for books containing "white" and "geometric" at Amazon.com yields the following:

Figure 2

From Mosaics, by
Fassett, Bahouth, and Patterson:

"A risco fountain in Mexico city, begun circa 1740 and made up of Mexican pottery and Chinese porcelain, including Ming.

The delicate oriental patterns on so many different-sized plates and saucers [are] underlined by the bold blue and white geometric tiles at the base."

Note that the tiles are those of Diamond Theory; the geometric object in figure 1 above illustrates a group that plays a central role in that theory.

Finally, the word "risco" (from Casa del Risco) associated with figure 2 above leads us to a rather significant theological site associated with the holy city of Santiago de Compostela:

Figure 3

Vicente Risco's
Dedalus in Compostela.

Figure 3 shows James Joyce (alias Dedalus), whose daughter Lucia inspired the recent entry Jazz on St. Lucia's Day — which in turn is related, by last night's 2:45 entry and by Figure 1, to the mathematics of group theory so well expounded by the putative saint Emil Artin.

"His lectures are best described as
polished diamonds."
Fine Hall in its Golden Age,
by Gian-Carlo Rota

If Pynchon plays the role of devil's advocate suggested by his creation, in Gravity's Rainbow, of the character Emil Bummer, we may hope that Rota, no longer in time but now in eternity, can be persuaded to play the important role of saint's advocate for his Emil.
 

Update of 6:30 PM 12/20/03:

Riddled:

The Absolutist Faith
of The New York Times

White and Geometric, but not Eternal.

Powered by WordPress