October 05, 2015

9:00 AM | El teorema de Mills: mucho ruido y pocas nueces
La búsqueda de funciones que generen números primos ha sido una constante en (prácticamente) toda la historia de las matemáticas. Los números primos, los “ladrillos” con los que se construyen los números naturales, han sido siempre un conjunto de números esquivo en el sentido de encontrar una expresión que los genere indefinidamente. Sabiendo esto, encontrar […]

October 04, 2015

11:06 PM | Configurations of Lines and Models of Lie Algebras (Part 1)
Learn a bit about the 27 lines on a smooth cubic surface.
10:15 PM | Argentan half-marathon [1 24′ 46″ – 22/496 – V2: 2/116 – 17°C]
A fairly good race in Argentan, despite (relatively) hot weather that saw the winning time increase by two minutes and a half. (Last year’s winner actually lost 3 and half minutes on the same track). Gaining 18 seconds over my time from last year was thus a significant achievement. This was my 17th—or 18th including […]
9:30 PM | Michigan Math In Action
Those of you who are interested in college math instruction may be interested in a no-longer-so-new blog “Michigan Math In Action”, which a number of our faculty started last year. (I was involved in the sense of telling people “blogs are fun!”, but haven’t written anything for them yet.) It mostly features thoughtful pieces on […]
6:00 PM | “Experimenting” with women-in-STEM stereotypes
When signing up for physics grad school, I didn’t expect to be interviewed by a comedienne on a spoof science show about women in STEM. Last May, I received an email entitled “Amy Poehler’s Smart Girls.” The actress, I read, had … Continue reading →
3:11 PM | Shared governance hits rock bottom at UBC, by Professor Stephen Petrina
The Board of Governors’ rejection this week of the Faculty Association’s request for accountability in President Gupta’s resignation marks the low point of shared or faculty governance at the University of British Columbia. It’s a shame that UBC sunk to rock bottom … Continue reading →
12:30 PM | 10/4/15
10 - 4 = 1 + 5Also:1 + 0 + 4 = 1 * 5Also:10 / √4 = 1 * 5
10:30 AM | (Vídeo) Pi and the Mandelbrot Set
Nuevo vídeo de Numberphile, en esta ocasión hablando sobre el conjunto de Mandelbrot y la relación del número Pi con este fantástico conjunto. Diversas imágenes en las que se hace zoom en el conjunto de Mandelbrot. Concretamente, hablan de la relación entre Pi y el conjunto de Mandelbrot que presentábamos aquí en esta entrada (¿que […]
7:27 AM | Aveiro, 3
Aveiro has something else, a reminder of the exit that awaits all of us:

October 03, 2015

11:36 PM | Interesting blog you're runnin' here, I must say!
I’m glad you enjoy it!
10:58 PM | 275A, Notes 1: Integration and expectation
In Notes 0, we introduced the notion of a measure space , which includes as a special case the notion of a probability space. By selecting one such probability space as a sample space, one obtains a model for random events and random variables, with random events being modeled by measurable sets in , and […]
10:15 PM | Banff snapshot [#3]
Filed under: pictures, Travel Tagged: Alberta, Banff, Banff Centre, BIRS, Canada, Canadian Rockies, Fall
12:30 PM | 10/3/15
1 + 0 + 3 = |1 - 5|Also:10 / (3 - 1) = 5
11:22 AM | Aveiro, 2
After two weeks in Aveiro, I know a little more about the place. The high-prowed boats that carry boatloads of tourists along the canals have a very different origin. They originally carried seaweed to farmers’ fields for use as fertiliser. … Continue reading →

October 02, 2015

10:15 PM | moral [dis]order
“For example, a religiously affiliated college that receives federal grants could fire a professor simply for being gay and still receive those grants. Or federal workers could refuse to process the tax returns of same-sex couples simply because of bigotry against their marriages. It doesn’t stop there. As critics of the bill quickly pointed out, […]
9:00 PM | Experience report: oral final exam
This past spring I taught a standard data structures course (stacks, queues, binary trees, heaps, asymptotic analysis, that kind of thing). Inspired by a group I participated in exploring pedagogy and course design—led by the wonderful Betsy Burris—I decided to … Continue reading →
6:54 PM | Accidental pies
This is the blackboard from the University of Edinburgh School of Mathematics common room from September 2015. I particularly noticed it because of the inadvertent appearance of P(ies) in the centre! I’m also enjoying the idea of pulsational energy.
6:15 PM | Argentan, 30th and 17th and 7th edition(s)
When I started the ‘Og, in 2008, I was about to run the 23rd edition of the Argentan half-marathon… Seven years later, I am once again getting ready for the race, after a rather good training season, between the mountains of the North Cascade and the track of Malakoff. with the last week in England, […]
3:39 PM | Oddities
A few odd things that I’ve run into recently: The IAS has a weekly meeting to discuss current topics in HEP theory. From their events calendar, next week’s meeting will be devoted to “The Cosmological Constant and the String Landscape”, … Continue reading →
12:30 PM | 10/2/15
10 / 2 = 1 * 5Also:3√(10 - 2) = √(|1 - 5|)
7:31 AM | Open science
I have written a three-part post for the CoDiMa blog on Open Science. The first part, open publication, is here; the remaining parts on open data and open software will appear in the next couple of days. Readers of various … Continue reading →
7:27 AM | Le Monde promotes socially responsible mathematics
You know you’re a Parisian intellectual when you are invited to make a totally gratuitous comment in Le Monde.  That has never happened to me, so however I may walk, talk, and quack, Brendan Larvor’s diagnosis of my status remains hypothetical.  And I can’t really say that Leila Schneps, whom I strongly suspect for numerous […]

October 01, 2015

10:15 PM | importance sampling with multiple MCMC sequences
Vivek Roy, Aixian Tan and James Flegal arXived a new paper, Estimating standard errors for importance sampling estimators with multiple Markov chains, where they obtain a central limit theorem and hence standard error estimates when using several MCMC chains to simulate from a mixture distribution as an importance sampling function. Just before I boarded my […]
1:29 PM | Kampfflieger und Bomben bei der Mathematik-Olympiade
Bei der All-Russischen Mathematikolympiade, der höchsten Stufe nationaler Olympiaden in Russland, gibt es immer wieder mal auch Aufgaben, die “praktischen” Problemen nachempfunden sind. 2009 zum Beispiel hatte man eine Aufgabe: Unter einer von n im Kreis angeordneten Tassen ist eine Münze versteckt. Mit jedem Zug darf man 4 Tassen auswählen und überprüfen, ob unter ihnen…
12:30 PM | 10/1/15
10 / (1 + 1) = 5Also:(√(10 - 1))! = 1 + 5
9:30 AM | Una de mates – Magia matemática
Segundo programa de Órbita Laika y segunda entrega de la sección Una de mates por parte de Raúl Ibáñez. El vídeo de esta semana se titula Magia matemática. Ahí va: Espero vuestras opiniones, pero tengo que decir que a mí este vídeo me ha gustado algo menos. La razón es muy sencilla: queda la posibilidad […]
1:52 AM | Personalizing Classroom Design
"I’ve seen first-hand how teachers are making an effort to “modernize” their own classrooms. Some teachers have ditched desks and moved towards tables."
12:17 AM | Fine Tuning Web Sketchpad’s Construction Interface
When the Web Sketchpad team created the interface for tools, there were lots of design decisions to be made. We made the best choices we could at the time, but after months of daily use, it became clear that at least one aspect of tool functionality needed some rethinking. In the original design of tools (which you […]

September 30, 2015

10:15 PM | a simulated annealing approach to Bayesian inference
A misleading title if any! Carlos Albert arXived a paper with this title this morning and I rushed to read it. Because it sounded like Bayesian analysis could be expressed as a special form of simulated annealing. But it happens to be a rather technical sequel [“that complies with physics standards”] to another paper I […]
8:50 PM | An exact square from a Reedy category
Any Reedy category has a canonical square of inclusions of subcategories and this square is exact.
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