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# Posts

### May 22, 2013

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In recent years there have been many claims made for “evidence” of a multiverse, supposedly found in the CMB data (see for example here). Such claims often came with the remark that the Planck CMB data would convincingly decide the … Continue reading →
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Let be a genus curve over the field of complex numbers. I’ve been trying to understand a little about special linear series on : that is, low degree maps , or equivalently divisors on that move in a pencil. Once the degree is at least , any divisor will produce a map to (in fact, many maps), […]
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The Canadian twitter world has been split in the last couple of days. You have of course the Duffy-Brazeau-Harb-Wallen-Wright-Perrin saga filling the trend boxes. But then, you have the story of the Tories’ problem with science, be it defunding, muzzling, … Continue reading →
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A well written note by Frenkel that attempts to explain Deligne’s work that won him this year’s Abel Prize.
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5 + 2 - 2 + 1 = 3! Also: 5 = |2 - (21 / 3)| Also: 5 - 2 - 2 = 1^3
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Von Verschiebungen erzeugte Drehungen. Die Neural Correlate Society veranstaltet seit 2004 jährlich den Wettbewerb ‘Best Visual Illusion of the Year’. Letzte Woche wurden die Preisträger 2013 bekannt gegeben. Der Siegertitel “Rotation generated by translations” kliegt wie die Überschrift eines Papers aus der Theorie der diskreten Bewegungsgruppen (nur dass es in der Mathematik keine von Verschiebungen…
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article on category theory
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The last chapter of Mathematical Structures was about how to spot false proofs. Of course, I am not the first to do this. A curious chain (I may tell about this later) led me to The Sophismata of Richard Kilvington. … Continue reading →
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Un bonito (y sencillo) ejercicio relacionado con el principio de inducción consiste en demostrar que el cuadrado de la suma de cualquier conjunto de enteros positivos consecutivos que comience en el 1 es igual a la suma de los cubos de dichos números. Es decir, que para todo se cumple que Podéis intentar resolverlo vosotros [...]Entra en Gaussianos si quieres hacer algún comentario sobre este artículo, consultar entradas anteriores o enviarnos un mensaje.Construye tú [â€¦]
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Why the recent breakthrough is important Yitang Zhang, of the University of New Hampshire, has apparently proved a finite approximation to the famous Twin Prime Conjecture. This is a result of the first order. After ten days of progressively more detailed news, including today’s article in the New York Times, Zhang’s 56-page preprint has just […]
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Vitaly Bergelson, Tamar Ziegler, and I have just uploaded to the arXiv our joint paper “Multiple recurrence and convergence results associated to -actions“. This paper is primarily concerned with limit formulae in the theory of multiple recurrence in ergodic theory. Perhaps the most basic formula of this type is the mean ergodic theorem, which (among […]

### May 21, 2013

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Today I’ve discovered a new kind of product of funcoids which I call “simple product”. It is defined by the formulas: and . Please read my book.
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As I was checking the recent stat postings on arXiv, I noticed the paper by Chen and Xie entitled inference in Kingman’s coalescent with pMCMC.  (And surprisingly deposited in the machine learning subdomain.) The authors compare a pMCMC implementation for Kingman’s coalescent with importance sampling (à la Stephens & Donnelly), regular MCMC and SMC.  The […]
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Con un poco de retraso, traemos el fallo (¿por qué se llamará fallo a la decisión de un jurado?) del jurado popular del Premio Carnaval de Matemáticas en su Edición de Abril de 2013. Y el ganador, con 18 puntos repartidos en 3 votos de 4 puntos y otros 3 de 2 puntos, es Meridianas, analemas e hipopedes del blog Revista Digital de Matemáticas Sacit Ámetam Aquí os dejo con el distintivo del ganador. Completan el podio la entrada El gran desafío de los increíbles, mucho más [â€¦]
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And so it came to pass, that an almost millenial quest found a safe resting place… Like all analytic number theorists, I’ve been amazed to learn that Yitang Zhang has proved that there exist infinitely many pairs of prime numbers with bounded by an absolute constant . So, how did he do it? Well, since [...]
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Enlightenment at a red traffic light Wolf Prize laureate Prof. George Daniel Mostow made his greatest scientific breakthrough while driving. Haaretz tells the story of how Dan Mostow reached his breakthrough known as Mostow’s rigidity theorem. Congratulations, Dan! French-Isreali Meeting … Continue reading →
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Knowledge is like an irregular blob. (thanks due to Jon Awbrey for the following quote) Thus, what looks to us like a sphere of scientific knowledge more accurately should be represented as the inside of a highly irregular and spiky object, like a pincushion or porcupine, with very sharp extensions in certain directions, and virtually […]
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Filed under: Mountains, pictures Tagged: Antarctica, climbing pictures, Posing Productions, Queen Maud, Ulvetanna
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The academic year finished off with two rather different events: my LMS–Gresham lecture about the Mathematical Structures course, and marking the approximately 270 scripts. The LMS–Gresham Lecture Last week I gave the annual LMS–Gresham lecture. When they asked me to … Continue reading →
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The previous section covered the case of $f \in L^2(\Omega^n, \pi^{\otimes n})$ with $|\Omega| = 2$; there, we saw it could be helpful to look at explicit Fourier bases. When $|\Omega| \geq 3$ this is often not helpful, especially if the only “operation” on the domain is equality. For example, if \$f : [...]
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5 = (2 * 1) + (1 * 3) Also: 5 + 2 - 1 = 1 * 3! Also: 5 - 2 = 1 * 1 * 3
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Una de las aspiraciones del ser humano desde tiempo inmemoriales es la de construir un mapa plano perfecto. Es decir, representar correctamente nuestro planeta, esférico, en un plano. Y muchos han sido los intentos de construir dicho mapa, aunque ninguno ha llegado a fructificar. ¿Por qué? ¿Acaso no existe el mapa perfecto? Sea cual sea [...]Entra en Gaussianos si quieres hacer algún comentario sobre este artículo, consultar entradas anteriores o enviarnos un mensaje.Construye [â€¦]
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It has been a busy two weeks all over the math community. Well, at least it seemed so to me. Some of my friends have defended their theses and need only to walk to receive their PhDs; I completed my topics examination, Brown’s take on an oral examination; and I’ve given a trio of math […]
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The grades are in for CS 124.  Hooray!Interesting trend : freshmen, who make up a small fraction of the class, are highly over-represented in the A and A- grades.  This has been happening for some years now.  Extension of the interesting trend : women freshmen*, who make up a smaller fraction of the class, are even more highly over-represented in the A and A- grades.I'd be very excited if I were teaching the class again next year -- finding undergraduates who have the potential [â€¦]
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The latest installment of math for six-year-olds… This morning once again I went into my daughter’s first-grade classroom, full of inquisitive girls, and made a mathematical presentation on the game of Nim.                    … Continue reading →

### May 20, 2013

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“The tone of his talks, he said, was “Let’s not talk about the plumbing, the nuts and bolts — that’s for plumbers, for statisticians.”” As I got a tablet last week and immediately subscribed to the New York Times, I started reading papers from recent editions and got to this long article of April 26, […]
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This year is the centennial of Paul Erdős’s birth. Erdős lived most of his adult life as a traveling mathematician, “couchsurfing,” as we would say now, from place to place and from mathematical conference to mathematical conference. He wrote more than 1,500 papers with more than 500 different coauthors, introduced the probabilistic method and was […]
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Bad news. My doctorate was revoked, explanation: “No-one graduates.” All my papers were rejected, the editors couldn’t find time to review them. I complained to my department and they said “Who are you again?” Of course, none of these things actually happened. The above words were transmitted by my counterpart in the bargain-bin parallel universe [...]
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Filed under: Wines Tagged: Chateau Larruau, Margaux
2,292 Results