Archive for the ‘art’ Category

Some january newslets

January 30, 2016

[Posted on january 30, 2015]

In no particular order :

  • the january issue of Gazette des Mathématiciens has just appeared, including among many other things a very nice overview of the proof of the Willmore Conjecture by Fernando C. Marques and André Neves, and also a dossier on Open Access publications in general and the example of the recent conversion of Annales de l’Institut Fourier in particular
  • for another example of a topic that is being well digested, there’s the work of Vincent Lafforgue on the Langlands program, which beyond the course by Michael Harris at Columbia, will also be the subject of a course by Sophie Morel at IPM in Tehran
  • two recent interviews of mathematicians in video, both at CIRM : Sylvia Serfaty and David Ruelle
  • the ceremony awarding the 2015 Fermat Prize to Laure Saint-Raymond and Peter Scholze will take place in Toulouse at the end of march. Note that the wording for Scholze’s citation starts with “pour l’invention des espaces perfectoïdes…“, a welcome non-Platonistic choice
  • another useless experiment of this blog’s host : turn left by \pi/2 at n iff n\pm1 are twin primes, else make a fixed step (say of +50) on a straight line. Plot. Here are the results up to n=1500 ; n=100,000 ; n=500,000 ; n=1,500,000. Resulting insight : nil…

turnattwin1500_gscale

 

turnattwin100000_gscale

 

turnattwin500000_gscale

 

turnattwin1500000_gscale

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Hibernation

September 14, 2015

This blog goes into a long hibernation of several months.  It might come back to life in 2016.  Any comment will stay into the moderation queue in the meantime.

Château d’Amboise under snow and ice.

Alternative title : the snow triangle.

(February 2012, CC BY-NC-SA 2.0).

Playing with the Matiyasevich-Stechkin visual sieve

September 9, 2015

Back in 1999, Matiyasevich and Stechkin proposed to visualize the sieving process that singles out the primes by using a parabola, which is fairly natural in hindsight. Here is a graph from a geogebra version :

matiyasevich_stechkin_sieve

That puts the sieve in the realm of Euclidean geometry, and it is very tempting to play with this construction a little bit. Here are some half-baked ideas, feel free to mention better ones…

One could try to map the primes so obtained by various transformations associated naturally to a parabola :

  • trying inversions (in particular through the vertex, and through the focus) for various values of the inversion radius would result in the primes being compactified to various line segments, so not something terribly insightful nor of artistic merit
  • the same would occur if looking at the inverse of the projection from a circle
  • in a different direction, one could of course move the parabola around within conic sections, resulting in lots of elliptic (compact) and hyperbolic (non-compact) images of the set of primes [this has very probably been considered before, any reference and keyword would be welcome!]

Another line of thought would be to set up some sort of billiard dynamics (or indeed wave dynamics) inside the parabola, e.g. sending light rays of pulses from each prime and looking at the resulting interference patterns over time, that might lead to some artistically pleasing visual patterns (an idea that might be explored at a later date)

A final thing that comes to mind is to try and construct constants that encapsulate some special features from the complete construction. One possibility I’ve looked at is to add the areas of the quadrilaterals that surround each prime, but if I got this right the sum is 2\sqrt{2} \sum_{p\in\mathbb{P},\ p\geq 7}\frac{p-1}{(p-2)(p-3)}, which unfortunately diverges…

 

Anticipating the Ramanujan biopic

April 19, 2015

Earlier this month, the TFI SLOAN Filmmaker fund announced its grantees for 2015, and the Srinivasa Ramanujan biopic The Man Who Knew Infinity, now in post-production, is among them.

That’s definitely a movie that could be inspiring indeed, given that Ken Ono has been very much involved in the project and the cast is full of competent actors, as mentionned in Adriana Salerno’s earlier informative blog post.

So its release will probably be a good opportunity to set up public conferences on related topics, or at least get prepared for some questions.

The wikipedia article seems to have a fairly comprehensive compilation of references that could be useful in this regard, including :

The Tombstone of Madame du Châtelet (1706-1749)

April 5, 2015

In 2006, to mark the tricentenary of the birth of first ever frenchwoman scientist, Émilie Du Châtelet, an exhibition was organized in Paris by Elizabeth Badinter (booklet here).

Then, a few years ago, several newly found mathematics and physics manuscripts written by la Marquise du Châtelet were sold at an important Christie’s sale.

What about the final resting place of such a fine woman? Well, it is a very sober black tombstone in Saint-Jacques church, in Lunéville. Elisabeth Badinter, and Annie Jourdain, tried to have something done so that it is not walked over by the faithfull, but there were no protective barriers when I visited a few days ago.

By the way, the Château de Lunéville, which sadly was ravaged by a fire in 2003, has been nicely restaured over a decade, and is well worth a visit. I went there early enough to catch a nice april cold fog.

(full album on flickr)

Forthcoming epijournals

March 7, 2015

Six months ago, I was wondering whether epijournals might be just around the corner, when in restrospect that wasn’t the case…

But very recently, the episciences.org website has listed the titles (and titles only for now) of three new journals, among which two seem to focus on mathematics : the Hardy-Ramanujan Journal, and Mathematica Universalis.

Obviously several people are hard at work on this, and probably doing things very carefully to ensure a smooth launch.

Flower 6.6.6 Work in progress, by Ella T. on flickr,

whose great gallery is not to be missed !

3D printing mathematical objects

June 21, 2014

With all the 3D printing craze, some folks have been trying to get mathematical objects. For instance here are some by fdecomite on flickr:

The details are a bit rough

but still it is quite decorative and I can imagine metal printing to be even nicer.

As for monochrome objects, some impressive ones have been attainable for a couple years, like this quadrifolium

Some geometric elegance

April 14, 2013

From a XIVth century Arabic manuscript (from Gallica), based on a treatise by Theodosius of Bithynia. I do wonder what this particular page says…

geocircle

Short MacArthur stats

November 18, 2012

The MacArthur Foundation rewards each year about 22 Fellows with a 5-year $500,000 grant given in instalments. The only eligibility requirement is that the laureates must be either citizens or permanent residents of the US.   Let’s see the break-up of recent classes.

– This year there has been 23 recipients. Most are US citizens educated there, the 5 exceptions being Israeli mathematician Chudnovsky (the only mathematician), German photographer Barth, Mexican-American film-maker Almada, and two frenchmen: bow-maker Rolland and optical physicist Guyon.

– Last year, the 22 laureates had 4 non-US educated ones:  German physicist Greiner, Cuban percussionist Prieto, Italian silversmith Vitali, and Japanese developmental biologist Yamashita.

– In 2010 there has been 23 fellows, among which: Chinese fiction writer Li, Israeli optical physicist Lipson, French economist Saez, and Chinese computer security specialist Song.

So, the general recent trends seem to be:

– about a half of the fellows are scientists broadly speaking, the other half being connected to the arts

– about 18% are non-US educated, and 82% are US citizens educated there

– mathematicians are rare: before Chudnovsky there has been Mahadevan in 2009, Tao in 2006, and then it goes back to Yau in 2000. They were more numerous in the eighties it seems.

 

 

Audentes fortuna juvat

July 12, 2012

Luna del 1 marzo 2012, by Skiwalker79 on flickr