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Eric Pouhier
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Lived in Paris, France
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Eric Pouhier

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This guy transforms energy into music with a real talent. 5mn of pulsing rhythm.
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Hypnotic !
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La marguerite qu'on n'a jamais fini d'effeuiller.
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IGOR LEVIT is a young pianist who has a quite personal way of playing Bach. An enchanting way actually with a strong sens of melodies.

He recorded some Bach partitas that I warmly recommend.

http://www.qobuz.com/fr-fr/album/johann-sebastian-bach-partitas-bwv-825-830-igor-levit/0886444410410 
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44 minutes of real cool montain's ridges ride in a modern glider, great images, perfect ambient sound, no music, good reading of the instruments. .. interesting comments.: awesome thanks a lot +Bruno Vassel​​ for sharing your flights. 
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If you're a fan of surrealism, you'll really enjoy this photoset.  The original photos were taken by the Romanian photographer Costică Acsinte; the colorized versions were made by the artist Jane Long.

http://colectiacosticaacsinte.eu/
http://janelong.fotomerchant.com/dancing-with-costica
Imgur: full of all the magic and wonders of the Internet.
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Eric Pouhier

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Wonderful harmonics illustration.
 
Yin and Yang

Can you say what's going on in this gif by intothecontinuum

If you get stuck, you can read the Mathematica code here:

http://intothecontinuum.tumblr.com/post/118477958368/maihudson-mathematica-code-an-t

But it's probably more fun to watch it carefully and see for yourself!
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Another fascinating aspect of mathematics brilliantly presented by Dr. Richard M. Green.
 
Fractals, Fibonacci, and factorizations

The rule for generating the famous Fibonacci sequence 1, 1, 2, 3, 5, 8, 13, 21, ... is that each number (after the first two) is the sum of the previous two numbers. The Fibonacci word is an infinite string of zeros and ones with properties reminiscent of the Fibonacci sequence, and the Fibonacci fractal, shown in the picture, is a way to represent the Fibonacci word in the form of a fractal.

One way to generate the Fibonacci word is to define strings of zeros and ones by the rules S(0)=0, S(1)=01 and S(n)=S(n–1)S(n–2) when n is at least 2. This gives rise to the sequence of strings 0, 01, 010, 01001, 01001010, 0100101001001, ..., whose limit, as n tends to infinity, is the Fibonacci word. There are other equivalent, but superficially very different, ways to generate this word, including (a) using an explicit formula for each digit given in terms of the golden ratio; (b) using a substitution rule; and (c) using the Zeckendorf representation of integers in terms of Fibonacci numbers.

By suitably interpreting the digits of the Fibonacci word as turtle graphics instructions in a Logo-like programming language, it is possible to represent the word as a fractal. More precisely, if one reads the digits in order, then the n-th digit corresponds to the following sequence of instructions:
1. draw a segment forwards;
2. if the digit is 0, then turn left 90 degrees is n is even, and turn right 90 degrees if n is odd.

The picture shows the result of this procedure after many iterations. The resulting curve has various interesting mathematical properties, some of which concern the square-shaped gaps. By inspection, we count one large square gap (in the middle, at the bottom); five smaller square gaps, and 21 square gaps of the next size down. The numbers of these gaps, sorted by size, turn out to be given by every third Fibonacci number starting with the second 1 (1, 5, 21, 89...) which means that there are 89 squares of the next size down. Furthermore, each square has a side length that is 1+√2 times the side length of the square of the next size down; the number 1+√2 is known as the silver ratio.

The recent paper Factorizations of the Fibonacci Infinite Word by Gabriele Fici (http://arxiv.org/abs/1508.06754) surveys some factorizations of the Fibonacci word and shows how to derive these factorizations using elementary properties of the Fibonacci numbers. In some cases, this gives easier derivations of the results than were previously known. An example of such a factorization involves the sequences S(n) from earlier. Proposition 1 of the paper proves that the Fibonacci word can be factorized as the infinite product 0.1.S(0).S(1).S(2)..., where the symbol . is used to separate the factors.

One of the most surprising factorizations in the paper is Proposition 9, which involves the reversals, T(n), of the strings S(n). The strings T(0), T(1) and so on are then given by the sequence 0, 10, 010, 10010, 01010010, ... Remarkably, the concatenation of the strings T(n) also gives the Fibonacci word, even though the ingredients being used to construct it are backwards and generally not palindromic. Another way to say this is that the Fibonacci word can be factorized as the infinite product T(0).T(1).T(2)...

Relevant links

The 2009 paper The Fibonacci Word fractal by Alexis Monnerot-Dumaine is an excellent guide to the mathematical properties of the fractal, and the picture of the fractal here comes from that paper. You can download the paper for free at https://hal.archives-ouvertes.fr/hal-00367972/document 
Monnerot-Dumaine's paper explains how to construct the Fibonacci word using a substitution rule, and explores what the fractal looks like if one makes turns at angles other than a right angle. 

Fici's paper explains how to construct the word using the Zeckendorf representation of natural numbers. It is a theorem that any positive integer can be expressed uniquely as the sum of one or more distinct non-consecutive Fibonacci numbers. This is called Zeckendorf's Theorem, even though Zeckendorf was not the first to prove it: https://en.wikipedia.org/wiki/Zeckendorf's_theorem

Wikipedia's article on the Fibonacci word gives an explicit formula for the n-th digit of the word and mentions many other interesting properties. For example, the Fibonacci word is often cited as the worst case for algorithms detecting repetitions in a string. https://en.wikipedia.org/wiki/Fibonacci_word

The On-Line Encyclopedia of Integer Sequences on the Fibonacci word: https://oeis.org/A003849

Wikipedia on turtle graphics: https://en.wikipedia.org/wiki/Turtle_graphics

I have posted about the Fibonacci word twice before, although not recently. 
My post from March 2013 discusses the word in the context of self-shuffling words: https://plus.google.com/101584889282878921052/posts/YnUkZ986LMM
My post from December 2012 discusses Fibonacci snowflakes and some generalizations of the Fibonacci word: https://plus.google.com/101584889282878921052/posts/KSuUFJV6tyv

If you're disappointed that I didn't talk about the golden ratio, have a look at the aspect ratio of the accompanying picture.

#mathematics #sciencesunday #spnetwork arXiv:1508.06754
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Merci +Richard Green 
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Refugees they are and they MUST be treated as such. I am ashamed by the way Europe is treating them.

#refugees #shame #tragedy

the battle over the words used to describe migrants - http://www.bbc.co.uk/news/magazine-34061097
Some believe the term migrant is no longer neutral.
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Cool toy !
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Eric's Collections
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Work
Occupation
Mathématiques, Photographie and Piano
Skills
Extreme curiosity, huge imagination & unlimited courage !
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Previously
Paris, France - Cherbourg - Balikpapan - Singapour - Abu Dhabi - San Fransisco, Usa - Brest
Story
Tagline
“Simplicity is the ultimate sophistication.” L. Da Vinci
Introduction
Bonjour,

Je suis né en 1963 à Brest, en France, depuis j'erre sur terre avec une certaine mélancolie et avec aussi une infinité de questions existentielles qui ne me laissent guère le temps de dormir. 

Fin 2008, j'ai décidé de reprendre l’étude des nombres comme Euclide le fit en son temps. De repartir de rien, de tout reprendre depuis le début, en effet, si un Grec ancien avait pu inventer la division et autres concepts avec très  peu d'outils et peu d'information. J'ai pensé qu'un homme du XXIeme siècle, habité par les maths, ayant un ordinateur, un excellent logiciel mathématique et un accès immédiat (merci Google & Wikipedia) à quasiment tout la connaissance du monde devrait pouvoir acquérir une meilleure compréhension du fabuleux monde des nombres. Après environ 9000 heures d'un travail tout aussi passionné qu'acharné, le 20 Juin 2012, j'ai finalement compris l’extraordinaire et incroyable Vérité sur la nature des entiers naturels... Lavoisier était encore plus dans le vrai qu'il ne pu l'imaginer "Rien ne se perd, rien ne se crée, tout se transforme. 

Quelques citations éclairées:

"La nature est fondamentalement mathématiquePythagore 

"Il ne faut pas craindre de se rebeller. La seule autorité quand on fait des mathématiques, c'est soi-même." Alain Connes

"La mathématique est une science dangereuse : elle dévoile des supercheries et les erreurs de calcul." Galilée

"Dieu a privilégié l'homme en mettant en son esprit les notions élémentaires des mathématiques afin de le faire participer au secret de sa création et aussi lui permettre d'améliorer sa condition."  Descartes 

"Mesure ce qui est mesurable et rends mesurable ce qui ne peut pas être mesuré." Galilée

"The Lord God is subtle, but malicious He is not." Albert Einstein

Any fool can make something complicated. It takes a genius to make it simple.” 
Woody Guthrie

 Quarante-deux ! (42) Deep Thought  (The Hitchhiker's Guide to the Galaxy)

"Tout ce qui est voilé sera dévoilé, tout ce qui est caché sera connu." Jésus the Galilean.

En dehors des mathématiques et de la musique, je m’intéresse à tout sauf à 2 domaines ou mon inculture est sans fond: la bande dessinée et le sport.

Pour finir, au fil des années, j'ai développé une certaine misanthropie et je compte sur vous pour en guérir.

Livre Préféré : The Road de Cormac McCarthy
Bragging rights
Bragging is lame.
Education
  • Autodidact
    Maths - Music, 1963 - 2015
    It is hard for me to know where all my knowledge comes from exactly. I have the chance to know many things, like forever ! I only accept as TRUE, concepts, ideas, theorems .... I have understood by myself.
Basic Information
Gender
Male
Looking for
Friends, Networking
Birthday
May 24, 1963
Other names
MORFLOW (PSN), BachMan (for being a big fan of JSB)