Camil Stoenescu's blog

Ce este – sau ce ar trebui să fie – un doctorat, explicat în 12 imagini:

de aici.

Descoperiți între 1980 și 2010:

via Popular Science.

Lucrurile se schimbă ușor-ușor într-un domeniu care a rămas practic neschimbat de aproape 600 de ani – cel al cărților tipărite. Într-o singură imagine sugestivă, Newsweek sintetizează situația actuală a celor două piețe (concurente):

O lectură interesantă despre declinul Barnes & Noble în Statele Unite – aici.

Ceea ce majoritatea oamenilor uită.

Folosind instrumente matematice se încearcă analizarea conflictelor armate din prezent:

IN 2003, US soldiers in Iraq were given a pack of playing cards showing Iraq’s"most-wanted". In the top position – the ace of spades – was Saddam Hussein. His sons Qusay and Uday were the ace of clubs and the ace of hearts. The message was simple: capture the entire pack, and regime change would be achieved and the war in Iraq won.

It hasn’t worked out to be that easy. Part of the reason is that in this age of terrorist attacks, insurgencies and "asymmetric" wars between parties of vastly differing firepower, the dynamics of conflicts have shifted irrevocably. Now mathematicians are starting to build models of how such present-day warfare plays out. As they do so, they are coming to the conclusion that it is time to rewrite the military rule book.

Mathematics can never hope to fully encapsulate the complex business of war. It has long been used, however, to suggest tactical approaches. During the first world war, for example, the English polymath Frederick Lanchester devised a series of equations to calculate the power balance between opposing forces in a classic symmetric war, in which two hierarchically organised armies fight until one keels over.

Lanchester showed that long-range weapons had changed such conflicts. In old-style one-on-one combat, an army’s strength was proportional to the number of men or guns at its disposal. Weapons that allowed many targets to be attacked simultaneously increased that potential, upping an army’s strength so that it was proportional to the square of its firepower. Concentrating your army’s firepower, dividing enemy forces, and removing opposition leaders to disable the units under their control were key tactics that followed (see "Lanchester in action").

De aici.

Murray Gell-Mann, descoperitorul quark-ului:

I’ve been warned Gell-Mann can be rather prickly when he feels his time is being wasted. To my relief, once we retire to his office he is amiable and gracious.

Gell-Mann’s work revolutionised our view of how matter works at the subatomic scale. In the 1950s and early 60s, when the catalogue of elementary particles was spiralling far beyond the familiar trio of proton, neutron and electron to reveal a menagerie of bizarre newcomers, particle physics was in desperate need of an organiser. No one did more to clear up the confusion than Gell-Mann, who came up with a tidy classification scheme that placed the particles into octets – groupings of eight.

He called his scheme the Eightfold Way – a playful allusion to the Noble Eightfold Path of Buddhism, which he happened to be reading about in preparation for a visit to India. The Eightfold Way soon led Gell-Mann to infer that the proton and neutron were not fundamental entities after all, but were in fact composites of a new kind of elementary particle. He called this particle the "quark", from a passage in James Joyce’s Finnegans Wake. Gell-Mann’s insight became the keystone of the standard model of particle physics, which explains most of the known fundamental forces and particles, and he earned the physics Nobel prize in 1969.[…]

Another pet project is an attempt to trace the majority of human languages back to a common root. Since the 19th century, linguists have been comparing languages to infer their common ancestry, but in most cases, Gell-Mann says, this kind of analysis loses the trail 6000 or 7000 years back. He says most linguists insist it is impossible to follow the trail any further into the past and – this is what truly rankles with him – "absurdly, they don’t even want to try".

Gell-Mann heads SFI’s Evolution of Human Languages (EHL) programme. The EHL linguists say they can go even further back by classifying language families into superfamilies and even into a super-superfamily. "What we’ve found," Gell-Mann explains, "is tentative evidence for a situation in which a huge fraction of all human languages are descended from one spoken around 20,000 years ago, towards the end of the last ice age." The team does not claim to account for all languages, though, and remains agnostic about whether they can eventually do so. "All of this just comes from following the data," he says.

De aici.

Este remarcabil că un om la optzeci de ani își păstrează intacte energia, curiozitatea și disponibilitatea de a învăța lucruri noi, având în vedere lipsa de interes pentru orice formă de cunoaștere – dincolo de ceea ce implică remunerație imediată – a atâtor oameni tineri…

Un studiu actual confirmă un adevăr vechi de când lumea: oamenii se asociază conform preferințelor și afinităților, evitând relațiile și interacțiunile problematice:

A new study analysing interactions between players in a virtual universe game has for the first time provided large-scale evidence to prove an 80 year old psychological theory called Structural Balance Theory. The research, published in the Proceedings of the National Academy of Sciences, shows that individuals tend to avoid stress-causing relationships when they develop a society, resulting in more stable social networks.

The study, carried out at Imperial College London, the Medical University of Vienna and the Santa Fe Institute, analyses relationships between 300,000 players in an online game called Pardus. In this open-ended game, players act as spacecraft exploring a virtual universe, where they can make friends and enemies, and communicate, trade and fight with one another.

Scientists currently study data from people’s electronic interactions, such as emails, mobile phones and online retail behaviour, to improve our understanding of human societies. Online games such as Pardus produce vast amounts of data that scientists can also use to study interactions between players, applying their findings to understanding the way that people interact in society.

Structural Balance Theory is an 80 year old psychological theory that suggests some networks of relationships are more stable than others in a society. Specifically, the theory deals with positive and negative links between three individuals, where ‘the friend of my enemy is my enemy’ is more stable (and therefore more common) than ‘the friend of my friend is my enemy’.

Din Science Daily.

Take "Humpty Dumpty sat on a…" Even this snippet of a nursery rhyme reveals how much languages can differ from one another. In English, we have to mark the verb for tense; in this case, we say "sat" rather than "sit." In Indonesian you need not (in fact, you can’t) change the verb to mark tense.

In Russian, you would have to mark tense and also gender, changing the verb if Mrs. Dumpty did the sitting. You would also have to decide if the sitting event was completed or not. If our ovoid hero sat on the wall for the entire time he was meant to, it would be a different form of the verb than if, say, he had a great fall.

In Turkish, you would have to include in the verb how you acquired this information. For example, if you saw the chubby fellow on the wall with your own eyes, you’d use one form of the verb, but if you had simply read or heard about it, you’d use a different form.

Do English, Indonesian, Russian and Turkish speakers end up attending to, understanding, and remembering their experiences differently simply because they speak different languages?

De aici.

Se pare că protonii sunt ceva mai mici decât s-a crezut până acum, mai precis cu 4% în circumferință, fapt ce ar putea avea consecințe considerabile asupra electrodinamicii cuantice actuale.

Nature:

The difference is so infinitesimal that it might defy belief that anyone, even physicists, would care. But the new measurements could mean that there is a gap in existing theories of quantum mechanics. "It’s a very serious discrepancy," says Ingo Sick, a physicist at the University of Basel in Switzerland, who has tried to reconcile the finding with four decades of previous measurements. "There is really something seriously wrong someplace."

Protons are among the most common particles out there. Together with their neutral counterparts, neutrons, they form the nuclei of every atom in the Universe. But despite its everday appearance, the proton remains something of a mystery to nuclear physicists, says Randolf Pohl, a researcher at the Max Planck Institute of Quantum Optics in Garching, Germany, and an author on the Nature paper. "We don’t understand a lot of its internal structure," he says.