science | Subluminal

3 February 2014

Julia

I’ve discovered a new language for scientific computation : Julia.

A quaternion Julia fractal

Here’s a description :

Scientific computing has traditionally required the highest performance, yet domain experts have largely moved to slower dynamic languages for daily work. We believe there are many good reasons to prefer dynamic languages for these applications, and we do not expect their use to diminish. Fortunately, modern language design and compiler techniques make it possible to mostly eliminate the performance trade-off and provide a single environment productive enough for prototyping and efficient enough for deploying performance-intensive applications. The Julia programming language fills this role: it is a flexible dynamic language, appropriate for scientific and numerical computing, with performance comparable to traditional statically-typed languages.

Among other things, it is very computationally efficient (it beats Matlab and Python by a large margin) and the syntax is very close to Matlab, making the transition very easy. And it is free !

I’ll let you know if I find it to be a viable alternative to commercial solutions…

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2 February 2014

2 Comments

english, mood, science life

Three algorithms

Here are three algorithms that I found pretty funny, and that make you think, while I was trying to find elegant solutions to some problem I faced.

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29 January 2014

english, mood, skepticality

Now that I have lived for over a year near the Silicon Valley, I have a better view of the local culture which is a strange mix of lefty utopian libertarian, lefty vegan liberals and all things that might seem contradictory in general, but not here.

Atlas Shrugged, in the liberal California

I want to address here what I’ve learned in these months, so that European newcomers can sharpen their learning curve !

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11 December 2013

english, Noble drawings, projects, science life

Strawberry fields forever

Today, I was lucky enough to go to the screening of “How I Came to Hate Maths” in Berkeley, where I had the occasion to ask Jean-Pierre Bourguigon and Cedric Villani for a drawing.

Here’s what came out of it.

First, I asked Cedric for a drawing of a spider in a truck, for he his well known for his work on optimal transport, and because he has the habit of wearing a spider broach. He added his signature, a marsupilami– not bad for a Fields medal recipient !

Then, I asked Jean-Pierre to draw me a spectrum, since it is, to me, what relates physics and mathematics the most

A spectrum, by Jean-Pierre Bourguigon and a spider in a truck by Cedric Villani

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Tagged araignee, berkeley, bourguignon, camion, comment j'ai detesté les maths, fields medal, french ambassy, how I came to hate maths, pacific film archive. BAM/PFA, villani

9 December 2013

art & science, français, gallery, projects, science

L’art et la science (VII) – Addendum

Cela fait longtemps que
1) je n’ai pas écrit en français
2) je n’ai pas ajouté de matériel nouveau sur l’Art et la Science.

Je vous propose de relancer la Z-Machine et de corriger tout cela dans ce post !

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27 November 2013

art & science, english, Noble drawings, projects, science

Two new Nobel drawings ! (… and uncharted drawings)

I’ve been working at the Lawrence Berkeley National Lab for a year now, and I wanted to get drawings from the two Nobel prizes that are still active in the lab : George Smoot (N2006) and Saul Perlmutter (N2011).

They both proved very difficult to find, since they are often travelling. But today, the day before Thanksgiving, I was particularly in luck : I spotted these two guys at the cafeteria !

The time I came back to my office to grab my notebook, Saul Perlmutter was gone, but George Smoot was still here !
I asked him to draw me a picture of the Cosmic Microwave Background. Here’s the result :

Smoot’s drawing

However, Saul Perlmutter had left. But… I knew where his office was. I went there; we talked a little bit.
A little earlier on, my friend Josquin told me that I would rather ask him a picture of a Supernova, probably easier to draw that the idea of universe expansion. Saul told me that this picture wouldn’t be personal, since his mind has been infused by the commonly accepted picture, and proposed to draw me a chart of the accelerating universe :

Perlmutter’s drawing

There we go ! (You can check my collection of noble drawings here)

Last month, I had the occasion to attend Uncharted, advertised as the local SXSW, thanks to a scholarship.

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11 November 2013

english, mood, resources, science life

Experimenting espresso coffee on American scientists

In the beginning of this year, I brought an espresso machine to my lab, since they only had drip coffee.
Drip coffee is good, and probably enough to keep you alert, but I missed the conviviality of sharing coffee with other people, especially people form other department- I owe to R. Hamming the habit of pollinating one’s mind with ideas from other. Plus, I soon discovered that American researchers don’t “waste” time having lunch with each other, which is pretty sad and, to me, opposed to the idea of research; I remember, back in Paris, how many times new ideas came up by talking about mundane matters to other researchers.

The conclusions of this initiative are available here.

Here’s an excerpt about coffee tasting :

Peet’s Coffee tasting

Enjoy your coffee !

(edit Dec 20th 2013) : Here’s a nice article by Matt Goudling on Japanese tradition blended with the art of making coffee : Daibo dreamed of coffee.

5 November 2013

english, epistemology, mood, skepticality

MOOCs are a hoax

…said Dev Patnaik at Uncharted, and I believe he is probably right.

Big institutions (elite schools) have no idea how to deal with PR, so MOOCs is a good way to increase their influence : it matters for the teachers only.
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18 September 2013

art & science, english, mood, Noble drawings, projects

Artists and Nobels

When I read “Thinking, Fast and Slow by Daniel Kahneman (that I mentionned in this post), he mentioned the existence of Edge.org, maintained by John Brockman, and the fact the he (DK) was asked by the latter to give his favorite equation.

It turns out that John Brockman has many wonderful connections and asked that same question to a whole bunch of great scientists.

Brockman’s self formula

Together with the Serpentine gallery, they curated the collection “What is your formula ».
This is astonishingly similar to what I try to do with the drawings I get when I encounter a Nobel prize, except that I actually get drawings, instead of formulas (and I’m almost sure my list is bigger than his !).

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6 July 2013

english, projects, resources, science