Alexandre Storelli

Science

Why small water drops move on hot pans: Leidenfrost wheels explained

As reported in 1756 by Johann Gottlob Leidenfrost, volatile liquids on hot solids form “gleaming drops resembling quicksilver”, a consequence of their levitation on a vapour cushion. This makes the drops spectacularly mobile, moving away as soon as they are deposited—an observation commonly attributed to gravity or surrounding airflows.

Science

How a Kalman filter works, in pictures

Surprisingly few software engineers and scientists seem to know about it, [even if] it is such a general and powerful tool for combining information in the presence of uncertainty. (...) You can use a Kalman filter in any place where you have uncertain information about some dynamic system, and you can

Business & Economy

Elinor Ostrom: Fighting the Tragedy of the Commons

Among the recipients of the 2009 Nobel Memorial Prize in Economics was Elinor Ostrom, for her analysis of economic governance, especially in relation to the commons. While this choice took many in the profession by surprise, her life-long quest for an understanding of successful common property resource management holds important

Management

The open source model can play an important role in innovation, but know its limitations.

Ten years ago, on May 22, 1997, a little-known software programmer from Pennsylvania named Eric Raymond presented a paper at a technology conference in Würzburg, Germany. Titled “The Cathedral and the Bazaar,” the paper caused an immediate stir, and its renown has only grown in the years since. It is

Technical

How Open-Source licenses apply to NPM dependencies and Full-Stack JavaScript development (2017)

Before I was not concerned about license of npm package. I could check the license of immediate dependency but never checking 3rd party (transitional) dependencies. And then I met guys from legal department. I now believe that developers should have a basic understanding of software licensing to have a constructive

Science

Physics beyond the Standard Model

Recent CERN experiments have once again validated a prediction of the standard model. This is embarrassing for scientists, as they are looking for experimental clues of limits of the standard model. Standard model is known not to explain everything. More about these alternative models below (source Wikipedia [https://en.wikipedia.

Comics

Dilbert: treadmills and cubicles

* All your employees are fat and unhealthy. That's why you should replace your outdated cubicles with treadmill desks. My company makes a treadmill desk that requires no electricity. * What if the employees don't like it? * They already hate everything about their jobs. There's no

Science

Geometry and Elasticity of a Knitted Fabric (Physical Review X)

Pulling on a knitted scarf can stretch it to twice its length, even though the thread it’s knitted from hardly elongates. Knitting is a timeworn craft, at least a thousand years old, but no satisfactory account of the mechanics of its stretchiness exists. New theoretical work describes how individual

Comics

In Which Jean-Paul Sartre Attempts to Return Some Socks (Existential Comics)

http://existentialcomics.com/comic/248

Business & Economy

Blendle: Journalism needs a Spotify, a Netflix, an iTunes — whatever you want to call it

Music has Spotify. Video has Netflix. But journalism still didn’t have its own dedicated platform. As a former technology journalist myself, I thought that the lack of such a platform for journalism was pretty strange. Spotify not only helps me access all music, it also makes it easy to

Technical

1500 Archers on a 28.8: Network Programming in Age of Empires and Beyond

This paper from Mark Terrano and Paul Bettner explains the design architecture, implementation, and some of the lessons learned creating the multiplayer (networking) code for the Age of Empires 1 & 2 games; and discusses the current and future networking approaches used by Ensemble Studios in its game engines. https:

Management

The Two Types of Respect Leaders Must Show

There is a free and abundant resource most leaders aren’t giving employees enough of: respect. The author explains the two types of workplace respect (owed and earned), how to communicate them, and what happens when you don’t foster both. https://hbr.org/ideacast/2018/07/the-2-types-of-respect-leaders-must-show

Science

Spin this disk - What color do you see?

Benham's top, also called Benham's disk, is named after the English newspaper-man, amateur scientist, and toymaker Charles Benham, who in 1895 sold a top painted with the pattern shown. When the disk is spun, arcs of pale color, called Fechner colors or pattern-induced flicker colors (PIFCs)

Society

Et si on quittait les réseaux sociaux ?

Ces derniers mois beaucoup de personnes hésitent à quitter les réseaux sociaux, pour fuir les trolls, pour gagner du temps ou pour arrêter d'en perdre. Faux mouvement ou vraie réflexion, nos rapports aux réseaux sociaux évoluent. Facebook devient peu à peu un réseau de vieux, les jeunes préfèrent

Technical

Another World: the French touch for videogames

The French creative aesthetic has always been a bit different from that of English-speaking nations. In their paintings, films, even furniture, the French often discard the stodgy literalism that is so characteristic of Anglo art in favor of something more attenuated, where impression becomes more important than objective reality. A

Society

Surveillance : le réseau français "intelligent" d'identification par caméras arrive

La reconnaissance faciale "intelligente" est annoncée comme une nécessité pour le ministère de l'Intérieur. Le modèle chinois de contrôle et surveillance de la population par des caméras et des algorithmes d'identification des personnes semble inspirer le gouvernement et l'administration française qui lance

Business & Economy

Crypto-monnaies et concurrence des monnaies

Solide article de vulgarisation sur les crypto-monnaies par Étienne Perrot pour la revue Études. Ci-dessous, le dernier paragraphe qui évoque le concept de concurrence entre monnaies privées développé par l'économiste Friedrich Hayek. Tous ceux qui, sans être nécessairement anarchistes ou Girondins, se méfient de l'incurie des

Society

You’d Need 76 Work Days to Read All Your Privacy Policies Each Year

(...) Researchers reviewed the top 75 websites on the Internet and found that the median length of their privacy policies was 2,514 words. Then they added another factor — how long it took an average person to actually understand what they were reading, which they found by giving simple comprehension questions

Society

Lifefaker: Life isn’t perfect. Your profile should be.

Lifefaker is the world’s first online life faking service. Instead of going through the hassle of living a perfect life, now you can just get the photos. [They] have thousands of photos of everything from toned abs to skinny flat whites. Just sign-up for one of [their] perfect packages

Philosophy

La peur de l'insignifiance (Carlo Strenger)

Depuis une quinzaine d’années, Carlo Strenger, philosophe et professeur de psychologie, observe un sacré phénomène lors de ses consultations : de plus en plus de patients sont très préoccupés par la crainte de vivre une vie qui n’a pas suffisamment de sens ; ce qu'il appelle « La peur

Technical

On Ethereum blockchain sharding

A detailed discussion about how the ethereum community plans to reduce the load on validating nodes by asking nodes to only store a specific subset of the blockchain data (a shard), while ensuring the security of the system. In particular, it talks about the challenges of atomic transactions across shards.

Society

Walking and bicycling are not as greenhouse gas friendly as you would think (Michael Bluejay)

Most people think that bicycling doesn’t use gas, but actually it does, indirectly. It takes lots of energy to produce the food for the cyclist’s effort — probably more than you thought. Of course, we can’t just stop eating, but we can definitely choose what we eat, and

Science

How likely it is for a nuclear war to occur? (Jorge Cham, 2017)

The author of PhD Comics has visited the Oak Ridge National Lab last year and has drawn a nice comic about what he learned there. It deals with the Nuclear Proliferation Treaty and how it is enforced to ensure correct/civil uses of fissile material around the globe. Nice read.

Management

Why Entrepreneurs Start Companies Rather Than Join Them (Steve Blank)

If you asked me why I gravitated to startups rather than work in a large company I would have answered at various times: “I want to be my own boss.” “I love risk.” “I want flexible work hours.” “I want to work on tough problems that matter.” “I have a

Science

What makes a tree a tree?

Despite numerous studies and 30-plus genomes under their belts, scientists are still struggling to nail down the defining traits of these tall, long-lived, woody plants. https://www.knowablemagazine.org/article/living-world/2018/what-makes-tree-tree HN discussion https://news.ycombinator.com/item?id=16792726