Around a week ago, I submitted the first paper to have me as the sole author. For someone working in such a large collaboration this is a pretty exciting moment, even if it is just proceedings

Last September, I was given the incredible opportunity to attend one of the most prestigious conferences in the world of quark-related research. The Strangeness in Quark Matter conference, held every few years, gathers physicists from around the world to an exotic location to discuss our current understanding of the strange quark, and the unusual behavior of the particles it creates. In September last year it was held in Buzios, a tiny fishing village on the coast north of Rio de Janeiro.  I was invited to give a talk at the conference, and I was lucky enough to get funding for the trip as I was also giving a talk on diffraction the week before in Rio (See Strong couplings: Tales from Brazil).

This was truly the most beautiful place I have ever seen (even compared to the stunning French snowy mountains I was falling down just a few weeks ago). It was also one of the strangest experiences of my life, and I am not attempting a pun. International conferences are a world unto themselves – indulgent in every sense. You feast frequently on a variety of delicious foods. You mingle with minds that are expertly extreme, taking various representations and interpretations of experimental analysis, sampling ideas and concepts from theorists from around the globe and across the field. Having never been to South America (or anywhere near as far as that) before in my life, the setting, for me, was entrancing and alien. Everywhere you looked there was a mango tree or a parasitic orchid hanging from a palm. Our buffets and breakfasts were adorned with Papaya and Guava. We were even treated to an exciting boat trip to a nearby island (nicknamed “ugly island”), and got to dive into the salty waters and snorkel!

Outside scheduled talk time we were constantly supplied with Caipirinas – cocktails with ice, sugar, lime and Cachaca (a spirit made from sugar-cane). In fact, after one long day, during a lively and late discussion that united the attendees with outstanding questions, drinks were brought round to encourage us to stay!

The topics under discussion, (and to some extent, debate), were just as unusual. At the start of my PhD, I had only known my own limitations in understanding data, theoretical concepts or predictions. Before the conference, discussion with many theorists to help me to understand the expectations for the LHC only served to confuse and excite me more. However, as well as answering a lot of questions for me, this conference demonstrated the true nature of being at the very front end of science – right now, we know very little for certain. Ask any scientist about what the LHC and RHIC heavy ion experiments are all about, and they will very quickly start to tell you about exciting things such as the “Quark Gluon Plasma”, and evidence to suggest its properties, like “strangeness enhancement”. Try saying either one of these phrases too loudly at a conference like this, however, and expect some funny looks. The fact is, there isn’t much you can say without a little skepticism (or careful rewording) right now.

One thing I know for sure is that my analysis area is not lacking in interest. Strange particle production in heavy ion collisions at RHIC, compared to pp collisions, can be explained quite powerfully by theory, but the phi resonance, which is not technically strange (made up of an s and anti-s quark) is somewhat more confusing. Asking what might happen to phi production in Pb-Pb collisions at the LHC is a tough enough question. However, begin to postulate what might occur in pp collisions with such high energy density that they become (in some ways) comparable to heavy ions, and you start to get some of those funny looks I mentioned. This was exactly what I did, and it sparked an argument between theorists of two extreme viewpoints, who eventually were asked to leave the room whilst the poor speaker continued. Of course, myself and another (very brilliant) ALICE physicist, Federico Antinori, who was keen to understand this issue, followed them out to take notes.

The conference was full of moments like this, and I am sure many of them are. Unusual data presented by experimentalists struggling to interpret it, theorists arguing passionately about the consequences. I’d like to make a rather controversial statement that there is probably an equivalent to the “Phlogiston” phenomenon at work in much of front-line science. (If you don’t know what I am talking about, don’t just Wikipedia it, you should also watch “Chemistry: A Volatile History”, presented by Prof. Jim Al-Khalili on BBC4 Catch up TV, and hurry as you only have a few days left!) What I mean is, wherever we are dealing with the unknown, there are many contradicting ideas and some of them have to be nonsense. Unfortunately what seems like nonsense can be exactly what we are looking for. You only have to look at the history and evolution of science to see how these red herrings can take a long time to unveil, and how what looks like a ridiculous mistake (parity violation, for example!) could turn out to be a curiously perfect answer.

I’ve been posting sporadically on how sunspots are starting to come back to the Sun, and I’m glad to see a new group sprouted up recently… and it’s a monster:

These images are from SOHO, the Solar and Heliospheric Observatory. The orange one is in visible light, and the sunspots are pretty obvious. The green one shows the Sun in the far ultraviolet, and you can see the sunspots are pretty intense, blasting out high-energy light. Sunspots are indicators of magnetic activity, and the intense magnetic field can accelerate plasma (ionized gas) to high energies.

Just so’s you know, a hundred Earths could fit across this image, so that oughta give you an idea of just how big these blemishes are.

What this means is that the Sun is becoming active again. You can see it better in this video I put together using SOHO animations. These are real SOHO observations. Note that some of the data are missing so the Sun’s rotation is a bit jerky, and that you can see that data dropouts and other problems plague these sort of observations. Oh– actually, another group popped up on the Sun earlier, too, and you can see those in the visible light data.

You can actually see the plasma flowing along the magnetic field lines in the latter part of the video.

Right now, the Sun is struggling to climb back up to the peak of its magnetic cycle, which will probably occur in 2013 or later, given how slow this has been — which you might want to keep in mind if some crackpot or scammer is trying to sell you on the idea that solar activity will destroy the Earth in 2012. When the Sun is at its peak, the magnetic field is at its strongest, and we see the most sunspots. However, the strongest solar flares and other explosive events tend not to happen until well after the cycle peaks, so it’ll be late 2013 or 2014 before we see the most vigorous activity, if the Sun holds to its previous behavior.

Again, people selling you on 2012 disasters generally have a very tenuous grasp on science. The less you know the better for them.

I expect we’ll be seeing more and more sunspots now as time goes by. It’s nice to see this happening, as it adds to the activity seen in December, and ends a long period of minimal sunspots — heck, for a long time, there were none at all. Boring. Now we can look forward to some exciting action again… just in time for SDO to launch, too!

[P.S. If anyone can tell me why the first few frames of my uploaded videos turn gray sometimes, that would be nice. I don't know whether to curse iMovie, Flash, YouTube, or all three.]

Image credit: SOHO (ESA and NASA)

The documentary ‘Higgs - Into the heart of imagination’ was broadcasted the 4th of February 2010 bij HUMAN on Dutch television. From today of on, the Dutch version of the documentary can also be watched online.

Leonard Susskind gives the first lecture of a three-quarter sequence of courses that will explore the new revolutions in particle physics. In this lecture he explores light, particles and quantum field theory.

Si je vous dis réseau de neurones, vous pensez certainement au cerveau, ou même si vous avez suivi des cours de biologie vous pensez aux synapses, dendrites etc… Mais ce n’est pas la ou je veux vous amener. Pour le moment.
Vous êtes vous déjà demandé comment était lu le code postal sur les enveloppes, ou encore comment le filtre anti-spam de votre messagerie préférée faisait pour stopper les mails indésirables ? Tout ceci demande une capacité à effectuer une décision reliée à un processus statistique. En effet, 2 personnes n’écriront jamais le même chiffre de la même manière et deux spams ne contiendront pas exactement les mêmes mots. Nous nous retrouvons face un ensemble d’éléments potentiellement infini tous différents les uns des autres et qui pourtant peuvent se regrouper en un nombre restreint de groupes de même caractéristique (ce caractère est un 3 ou encore ce mail est un spam…).

C’est dans cet objectif de tri que sont utilisés ce qu’on appelle des algorithmes d’apprentissage, dont font partie les réseaux de neurones artificiels. Ceux-ci vont être capable d’apprendre à identifier une certaine caractéristique dans un échantillon qui lui est soumis.

Architecture d'un réseau de neurones

Les réseaux de neurones sont basés sur un modèle simplifié du neurone biologique, ils se composent généralement de neurones d’entrée, puis une couche dite cachée enfin une couche de sortie (voir schéma). Le tout reliés par des synapses. En entrée seront donnés les différents critères utiles au tri (par exemple l’occurrence de certains mots pour l’identification de spams), en sortie sera la réponse du réseau (c’est plutôt un spam ou non).
Mathématiquement le principe repose sur le fait que n’importe quelle fonction peut être approximée par une combinaison linéaire de fonctions d’activation ( sigmoïde, tangente hyperbolique ou fonction de Heaviside ). Ainsi chaque neurone se trouve doté de cette fonction et chaque lien entre les neurones (synapse) est pondéré suivant le problème à résoudre.

Un tel réseau est à la base parfaitement stupide, il ne sait rien faire à part un traitement purement aléatoire de l’information. Comme quand vous voulez apprendre à faire quelque chose, il va falloir s’entraîner!
Durant cette étape nous allons soumettre à notre algorithme un échantillon de caractéristiques connues à trier. On pourra ainsi comparer la réponse du réseau à la réponse correcte. Sachant cela, nous pourrons améliorer le résultat en modifiant les poids synaptiques. Apres plusieurs essais, le réseau de neurones aura une sortie proche de celle attendue et sera désormais prêt à utiliser ses capacités sur un échantillon quelconque.
L’analogie avec l’apprentissage humain est très fort : imaginez que je doive apprendre à quelqu’un à reconnaître une souris d’ordinateur. Je vais lui présenter plusieurs objets en lui disant à chaque fois si c’est une souris. Si je lui montre un nombre important de souris (diverses et variées), il va au final réussir à repérer les caractéristiques pertinentes et va pouvoir en extrapoler un «concept souris». Après la phase d’apprentissage, la comparaison à ce concept général sera utilise à chaque fois qu’il devra reconnaître une souris :
«Ah d’accord… Une souris est plus ou moins ovale, possède deux boutons et parfois un bouton au milieu, et elle est souvent raccordée par un fil etc…  Donc si je vois toutes ces caractéristiques sur un objet, j’aurai de bonnes chances de présumer que c’est une souris d’ordinateur».

Très bien, mais je suis un peu loin de la physique des particules ici n’est-ce pas? Alors revenons-y.
En physique des particules, le principe critique est de pouvoir discerner un phénomène bien particulier (le signal) au milieu des millions de collisions amenant à des phénomènes qui ne nous intéresse pas (le bruit de fond). Autrement dit, trouver l’aiguille dans la botte de foin… La théorie physique sous-jacente aux phénomènes observes dans les collisionneurs de particules étant la mécanique quantique, nous ne pouvons jamais avec certitude connaître l’issue d’une collision en particulier. Nous ne pouvons donner que les probabilités.
La méthode première pour augmenter nos chances est d’effectuer des «coupures» : je ne regarde que ce qui a une énergie supérieure à un tel seuil ou encore je ne prend que ce qui a été détecte dans une certaine partie du détecteur etc… Car je sais que c’est dans ces cas que j’ai le plus de probabilités de trouver mon bonheur.
C’est exactement ce que va faire un réseau de neurone, mais de manière optimisée, il va, de part son entraînement, apprendre à ne sélectionner que les évènements possédant les caractéristiques qui ont le plus de chance d’être du signal et rejeter tout ce qui a de fortes chances d’être du bruit de fond.
Le sujet de ma thèse est justement de mettre en évidence un phénomène particulier qui fait intervenir le boson de Higgs et de par la même découvrir (ou exclure) son existence. Il faut savoir que ce phénomène a une probabilité extrêmement faible de survenir, il est donc crucial de pouvoir trier ces évènements. C’est pour cela que je travail a l’aide de réseaux de neurones adaptés à la reconnaissance de ce phénomène.

Akinator, une application internet capable de deviner à quoi vous pensez grâce a un algorithme d'apprentissage.

L’intérêt pour les réseaux de neurones et les algorithmes d’apprentissage en général n’a cessé de croître ces 20 dernières années et sont couramment utilisés dans des domaines aussi variés que les milieux financiers (prédiction des fluctuations de marches), dans le domaine bancaire (pour déceler les fraudes aux cartes de crédit), en aéronautique (pilotes automatiques), en intelligence artificielle etc… Même certaines applications internet se vantant de pouvoir lire dans vos pensées ont vu le jour sur la toile comme 20q ou encore Akinator et utilisent ces algorithmes.

Nous pouvons voir que ces nouvelles techniques d’analyse ont un bel avenir devant eux. Au delà des applications sans cesse plus nombreuses, celles-ci s’améliorent de jour en jour grâce au travail des chercheurs et deviennent ainsi plus puissantes, plus rapides et plus précises. Mais comme nous l’avons vu, malgré le mot neurone, nous sommes encore bien loin d’un cerveau humain. Alors avant d’imaginer une invasion de robot tueurs, sachez bien que Terminator sait pour le moment à peine lire et que c’est déjà pas mal!

First off, we should mention here that CMS’s first paper from collision data has now been accepted for publication by the Journal of High Energy Physics. It’s a measurement of the angular distribution and momentum spectrum of charged particles produced in proton collisions at 0.9 and 2.36 TeV, using about 50,000 collision events recorded in December. It is really wonderful that this result could be turned around so quickly! The first of many papers to come, we hope.

Meanwhile, as already mentioned here, we now have the news of the run plan for the LHC. CERN is preparing for the longest continuous accelerator run of its history, 18 to 24 months. The inverse femtobarn of data to be recorded in that time is a lot, and will give us an opportunity to make many interesting measurements. Whether any of them will be evidence of new physics, I for one am not going to speculate! But if nothing else, this plan sets out what our LHC life for the next ~three years is going to look like.

But a shorter-term question comes to mind — 1 fb-1 over 18 to 24 months is one thing. But what about just the next few months? There is a major international conference coming up in July. What sort of LHC results might be ready by then? That will depend in part on how many collisions are delivered. I’ve seen various estimates for that, but they vary by an order of magnitude depending on the level of optimism, so I’d rather not guess. It will also depend on the experiments’ performance. How efficiently can we record those collisions? How quickly can we process them? How soon will we understand various parts of the detectors well enough to make quality measurements? How smart and clever can we be throughout the entire process? How much sleep is everyone going to get?

Ask me again in July. Meanwhile, game on.

A sliver of sunlight on the next mountain, amidst clouds and snowfall.

I’ve been a bit slow with blogging lately… And the reason is not a lack of things that are going on, far from that. Things got even more busy because of a long-planned week of skiing, and all the things I had to finish before then. Now, teaching is over for this semester, and since yesterday around noon, we are in a small mountain village in south western Austria.

Over the last few days there has been quite a bit of fresh snow, good for the slopes, but bad for visibility, especially since the clouds this morning were right at the altitude of the ski resort. After lunch, we saw a first sliver of sunlight, and the day ended with sunshine. The snow was great to ski on, but of course in the middle of a cloud I went into a little depression a bit to fast without seeing it, and jolted my back. But the sauna in our hotel hopefully helped to loosen the muscles again… Nothing like baking for a while to kill the pain of a long day of skiing.

I hope that over the next few days I’ll also have the time to write a bit about things that have been going on lately: A submitted paper, meeting in Paris, maybe more…. But no promises, skiing comes first!

The tool to soothe sore muscles: The sauna in our hotel in the ski resort.

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The Solar Dynamics Observatory, due for launch on February 9 at 10:30 Eastern time (15:30 GMT), is a revolution in solar observing: equipped with state-of-the art detectors, it’ll stare at the Sun and teach us far more about our closest star than we’ve ever had a chance to before. It’s like SOHO on steroids.

I was going to write up a lengthy post about it, but then I found out my friend Nicole Gravitationaliotta, aka The Noisy Astronomer, already put together a great post about it. That saves me time.

Something I want to point out: SDO will have a continuous science data streamrate of a whopping 16 megabytes per second. You might want to read that again. That’s 1.4 terabytes per day, or half a petabyte per year. Given that a Blu-Ray disk holds 50 gigabytes at most, that means SDO would fill 28 disks a day just to store that data. Cripes. That’s a vast amount of data to sift through. If the Sun is hiding anything, it has about a week to figure out what to do. After that we’ll be watching everything it does.

Also, a fun thing about this for me is that the project scientist for SDO is Barbara Thompson, a woman I’ve known a long, long time: her office was across from mine when I was working on Hubble, and I would often drop by to swap stories with her and generally mix it up. It’s very cool to know that an old friend will be helping run such a fantastic astronomical instrument.

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The study of reciprocity between mobile phone users reveals surprising insights about the flow of information in society.

What do your mobile phone habits say about you? Probably more than you might imagine.

At least, that's the suggestion from Lauri Kovanen and pals at the Aalto University School of Science and Technology, Finland. These guys have studied the 350 million calls made by 5.3 million customers over an unnamed mobile phone network during a period of 18 weeks. The primary question they ask is whether mobile phone calls are mutually reciprocated: in other words, does somebody who calls another individual receive in return as many calls as he or she makes, a phenomenon known as reciprocity.

Mobile phone calls are a particularly good way to study reciprocity because they are directed in a way that sms messages and email are not. In a mobile phone call, the caller initiates the conversation and then both parties invest a certain amount of time in the event. But afterwards there is usually no immediate reason for the recipient to call back. So it's clear who initiated the event.

But SMS messages or e-mails are entirely different: here a conversation usually means sending a sequence of reciprocated messages and this makes it much more difficult to study reciprocity by simply counting the number of messages.

This has allowed Kovanen and company to unearth a number of interesting phenomena. For a start, the calling patterns of prepaid users is very different from those with a contract who pay later. Postpaid users tend to be more prolific, having on average 5.41 people they call.

Prepaid users, by contrast, have only 3.41 contacts on average (although the notion of "average" is a little strange here since there is a very long tail on these distributions).

Not only that but postpaid users make 10 times as many calls as prepaid users. "We can also see that prepaid users receive more calls than they make, while the most active postpaid users make more calls than they receive," says Kovanen and company.

Prepaid users are also have more skewed relationships. Among prepaid users, the relationships where one participant makes more than 80 percent of all calls make up over 25 percent of the total.

The figures for postpaid users are far less skewed but they are greater than you'd expect from an ordinary probabilistic distribution in which each party in a relationship was just as likely to call the other.

So what's the difference between prepaid and postpaid callers? One of the most important is probably that prepaid users are much more likely to be young people. And sociologists already know that relationships between young people tend not to be equally reciprocated.

A few years ago, the National Longitudinal Study of Adolescent Health asked US students to name up to five of their best friends. Between them, the students named 7,000 individuals but only 35 percent of the nominations were reciprocated. So perhaps it's not suprising that a similar picture emerges from the study of mobile phone calls.

More puzzling is the skew in reciprocity in postpaid users which may not be as significant as for prepaid users but is still worthy of note.

What Kovanen and co are uncovering may be some fundamental property of human relationships; only more study will reveal that.

But the work is important for another reason: the skewed reciprocity between mobile phone users may influence other things such as the spread of ideas and information in society or, just as likely, the spread of viruses.

And that could have important implications for the way antivirus efforts are organised and directed.

Ref: arxiv.org/abs/1002.0763: Reciprocity of Mobile Phone Calls

Somewhere in HM Treasury or thereabouts, 2007.

The STFC Proposal

(Thanks to the Batman Comic generator)

The theoretical physics laboratory of Riken, to which I belong to, is a part of Nishina accelerator center. The center has a huge accelerator which is specialized for “RIBF”, RI beam factory, with a world-”strongest” superconducting ring cyclotron. You can find movies on how isotopes are accelerated in the beam lines, at the webpage of the Nishina center. My research is on superstring theory but I am currently applying string theory technique to nuclear physics, so this Nishina center is a perfect place for me to get in touch with real nuclear experiments.

Last week, hosted by the director of Nishina center, we had a big party, with alcohol drinks and cakes. This was a get-together party, which the director aimed to have all of the center members to know each other. I eventually enjoyed this party since, as the director aimed, I have met one person who is a visiting experimentalist working in Italy. Her experiments sound very interesting to me, and in fact quite much related to my recent work on strange physics. We talked at the party, and we made a promise that we would get together sometime soon. However, to tell you the truth, I haven’t expected much on this promise, as this was at a party and we have met just for the first time, and I am just a string theorist who should look apparently “different” from nuclear experimentalists. However, on the next day, in the morning, she came to my room! — and we had a good discussion. It was amazing to me that, just at this get-together party, I happend to see an interesting person and could talk really on my project, although she came from the other side of the globe. I thank Nishina center, and the director En’yo.

I hope to report on the progress of my research, on the application of superstring theory to nuclear physics, here. As for my current project, my Mathematica says “I need more memory”…. well, I’ll try to write a new and beautiful code which may cost less memory, hopefully.

The best of the rest from the Physics arXiv this week:

Complex Networks: New Trends For The Analysis of Brain Connectivity

Soccer: Is Scoring Goals a Predictable Poissonian Process?

Optical Chirality Without Optical Activity: How Surface Plasmons Give A Twist To Light

Long-Lived Quantum Coherence in Photosynthetic Complexes at Physiological Temperature

Locomotion of Electrocatalytic Nanomotors due to Reaction Induced Charge Auto-Electrophoresis

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This is an idea that has been bouncing around for a while, but is now apparently seen in experiments: real-world photosynthesis taking advantage of quantum mechanics. (Story in Wired, via @symmetrymag. Here’s the Nature paper on which it’s all based.)

The idea is both simple and awesome: you want to transport energy through an “antenna protein” in a plant cell to the “reaction-center proteins” where it is chemically converted into something useful for the rest of the plant. Obviously you’d like to transport that energy in the most efficient way possible, but you’re in a warm and wet environment where losses are to be expected. But the plants somehow manage the nearly impossible, of sending the energy with nearly perfect efficiency through the judicious use of quantum mechanics.

We can think about this in terms of Feynman’s way of talking about quantum mechanics: rather than a particle taking a unique path between two points, as in classical mechanics, a quantum particle takes every possible path, with simple paths getting a bit more weight than complicated ones. In the case of the protein, different paths for the energy might be more or less efficient at any particular moment, but this bit of quantum trickery allows the energy to find the best possible route at any one time. Imagine at rush hour, if your car could take every possible route from your home to the office, and the time it officially took would be whatever turned out to be the shortest path. How awesome would that be?

The reason you can’t do that is that your car is a giant macroscopic object that can’t really be in two places at once, even though the world is governed by quantum mechanics at a deep level. And the reason for that is decoherence — even if you tried to put your car into a superposition of “take the freeway” and “take the local roads,” it is constantly interacting with the outside world, which “collapses the wave function” and keeps your car looking extremely classical.

Proteins in plants aren’t as big as cars, but they’re still made of a very large number of atoms, and they’re constantly bumping into other molecules around them. That’s why it’s amazing that they can actually maintain quantum coherence long enough to pull off this energy-transport trick. Previous studies had hinted at the possibility, but only by cooling the proteins down and shielding them from external jiggling. This new work happens at room temperature in the context of marine algae, so it seems to indicate that it can happen in real environments.

One step closer to building my teleportation machine. Get to work, quantum engineers!

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New calculations reveal that p-doped graphane should superconduct at 90K, making possible an entirely new generation of devices cooled by liquid nitrogen.

There's a problem with high temperature superconductors. It's now more than two decades since the discovery that certain copper oxides can superconduct at temperatures above 30 K.

Those years have been filled with promise, hyperbole and feverish research. Physicists know that copper oxides superconduct in an entirely different way to conventional BCS superconductors (after Bardeen, Cooper and Schrieffer, who worked out the theory behind them). And yet, nobody agrees on precisely what the new mechanism is. Neither has anybody created a superconductor that works at a usable temperature, that is above the temperature of liquid nitrogen.

Even the resurgence of excitement last year over the discovery that magnesium diboride superconducts at high temperatures, probably in the old fashioned BCS way, soon gave way to malaise as physicists found they were unable to build on the breakthrough to make better superconductors. It's tempting to think that superconductors will never pass the liquid nitrogen barrier.

But today hope is restored thanks to a fascinating set of calculations carried out by Gianluca Savini at the University of Cambridge in the UK and a couple of buddies. They calculate the properties of p-doped graphane from first principles and say that it ought to superconduct at a balmy 90K or more, well within the range of liquid nitrogen cooling.

What's more p-doped graphane should superconduct in the same way as the old fashioned BCS superconductors. That's curious because everybody believes that BCS superconductivity cannot work at high temperatures.

The reason is the energy of the interaction between the superconducting electrons and the surrounding material. In ordinary BCS superconductors this is thought to be just a few tens of meVs. In the copper oxides, however, these interactions have an energy of a few hundred meVs. It's this difference, that makes physicists think that BCS superconductors will never work at the temperature of copper oxides.

And yet the discovery that magnesium diboride superconducts challenges that thinking--energy of these interactions in MgB2 is much higher. Three factors seem to come together to make it possible, say Savini and co. First is the characteristic energy of the phonons in MgB2 which is due to bond stretching and plays an important part in helping superconductors through the structure. Second is the electron density of states in the material and finally they point to the balance between the attractive electron-phonon coupling and the repulsive electron-electron interaction in MgB2.

Might it be possible to find materials in which these quantities can be manipulated further? You betcha. Savini and co noticed that p-doped diamond has two of these characteristics but superconducts only at 4K.

However, they calculate that p-doped graphane fits the bill exactly and should superconduct in the old-fashioned BCS way at 90K. What's more they say there are hints that p-doped diamond nanowires might have similar properties.

Various groups are already playing around with doped diamond nanowires.

The implications of all this are astounding. First up is the possibility of useful superconducting devices cooled only by liquid nitrogen. At last!

But there's another, more exotic implication: by creating transistor-like gates out of graphane doped in different ways, it should be possible to create devices in which the superconductivity can be switched on and off. That'll make possible an entirely new class of switch.

Before all of that, however, somebody has to make p-doped graphane. That will be hard. Graphane itself was made for the first time only last year at the University of Manchester. It should be entertaining to follow the race to make and test a p-doped version.

Ref: arxiv.org/abs/1002.0653: Doped Graphane: a Prototype High-Tc Electron-Phonon Superconductor

Pity poor Pluto. The debate over its planethood has caused much consternation over the years. Part of the problem is that it’s so dinky and so far away! If it were closer, or bigger, we almost certainly wouldn’t be having this debate.

But whether or not you think Pluto should be part of the gang or not, one thing is certain: it’s a world unto itself. And to bring this point literally home, the Hubble Space Telescope has revealed the changing face of this tiny iceball:

These images, just released today (but taken in 2002), represent the most detailed surface map of Pluto ever taken. Even in Hubble’s Advanced Camera for Surveys Pluto is only a few pixels across, but it’s possible using sophisticated image processing techniques to tease out the detail seen.

Here’s a nifty animation of Pluto rotating using these maps:

Very cool. But these maps are more than just eye candy. They show significant changes on Pluto’s surface since the last maps were made using Hubble 16 years ago. Pluto’s north pole is brighter and the south pole darker, implying that material has migrated from one pole to the other, or at least that the poles are changing in different ways. Pluto orbits the Sun "on its side", dramatically more tilted than Earth’s mere 23.5°. Right now, the north pole of the world is facing the Sun, meaning it’s summer on Pluto’s northern hemisphere (as it’ll remain for a long time, given Pluto’s 248 Earth-year long year).

Not only that, these images show that Pluto has reddened quite a bit in the past few years. This is one reason it took so long to release the images; Marc Buie, the astronomer who took them, saw some things in the data that were difficult to understand, and wanted to make sure they were correct. These images are composites of pictures taken using a blue and a green filter. During the time these observations were made, in 2000 – 2002, Pluto got much darker in blue, which was unexpected. Pluto’s moon, Charon, did not get any bluer, indicating that the cause was something intrinsic to Pluto and not that something weird happened with Hubble.

So why is Pluto redder now? That’s not clear. In general, ultraviolet light from the Sun interacts with the chemicals on Pluto, creating reddish organic molecules; this is seen on lots of distant, icy objects in the Kuiper Belt (the region past Neptune where Pluto orbits). Incredibly, even at the numbing distance of over 4 billion kilometers (3 billion miles) from the Sun, Pluto is still strongly affected by it. But this is happening while overall the northern hemisphere got brighter and the southern darker. You’d expect Pluto to get darker if it gets redder, so clearly there’s more going on here than meets the eye.

These maps will prove crucial in planning the imaging run of the New Horizons probe, which will scream past Pluto in 2015. Having even a crude map in advance of the encounter will help scientists plan their limited time more carefully.

Plus, these Hubble images may very well be the best view we’ll get until New Horizons gets to Pluto, for that matter. And whether you think Pluto is the littlest planet or one of the biggest of the Kuiper Belt Objects, it’s a fascinating place worthy of a lot more study. And in just a little more than five years we’ll see fantastic images of it, too. I can’t wait!

Video courtesy Emily Lakdawalla (and my thanks to her for a helpful conversation). Image and video credit: NASA, ESA, and M. Buie (SwRI)

Super Bowl Sunday is, of course, the great American holiday. Past years have seen inspirational performances by Joe Namath, Joe Montana, and Janet Jackson. This year pits the New Orleans Saints against the Indianapolis Colts. New Orleans, of course, is known as a city of saintly behavior, while Indianapolis’s claim to fame involves horsepower in some tangential way.

When faced with contests of ritualized violence, we like to look for the science. So check out this video of Saints quarterback Drew Brees participating in a rigorous laboratory experiment by throwing the ol’ pigskin at an archery target. Joking aside, that is some pretty sick accuracy there.

Impressive that a human arm beats a bow and arrow for accuracy (although it’s not completely clear that the distances and conditions were perfectly analogous). All in the wobble, apparently. But if I were defending my castle from the barbarian hordes or something, I’d still prefer archers over some guys throwing footballs.

Last week, the Chamonix workshop once again proved its worth as a place where all the stakeholders in the LHC can come together, take difficult decisions and reach a consensus on important issues for the future of particle physics. The most important decision we reached last week is to run the LHC for 18 to 24 months at a collision energy of 7 TeV (3.5 TeV per beam). After that, we’ll go into a long shutdown in which we’ll do all the necessary work to allow us to reach the LHC’s design collision energy of 14 TeV for the next run. This means that when beams go back into the LHC later this month, we’ll be entering the longest phase of accelerator operation in CERN’s history, scheduled to take us into summer or autumn 2011.

There has been a great deal of speculation about how a major research funding body – the Science and Technology Funding Council – has lurched from one financial crisis to another.

Yesterday in the evidence session of the Science and Technology Select Committee, we heard Michael Sterling, chair of the STFC, give a crystal clear description of the fundamental problem.

… see the rest of this article I wrote on the New Scientist’s S-Word.

While working on the contribution, I was hugely conflicted, for many reasons (variety of themes, variety of pieces, art forms, only 100 words, etc...) and another major theme struggled for dominance - "essence". How both science and art strive to identify the essential truth about a subject. My original contribution that I submitted to the editors to get their feedback on whether I was on the right track for what they were looking for therefore had a bit more of this in it, and referred to two pieces of art (I eventually chose one and focussed on developing and rewriting around that, using the "transcendence" theme). The piece I used that did I did not use for the final article is perfect for illustrating the "essence" theme, and so to provoke some thoughts in you [...] I include it here, along with some fragments of the paragraphs I was playing with at the time:

The manned space flight program masquerades as science, but it actually crowds out real science at NASA, which is all done on unmanned missions. In 2004 President George W. Bush announced a new vision for the space agency: a return of astronauts to the moon followed by a manned expedition to Mars. A few days later NASA's office of Space Science announced major cutbacks in its important Beyond Einstein and Explorer programs of unmanned research in astronomy. The explanation was that they "do not clearly support the goals of the President's vision for space exploration."

Soon after Mr. Bush's announcement I predicted that sending astronauts to the moon and Mars would be so expensive that future administrations would abandon the plan. This prediction seems to have come true.

A new technique for analyzing early English texts is gradually revealing the history of the apostrophe.

Last year, grammatical tragedy struck in the heart of England when Birmingham City Council decreed that apostrophes were to be forever banished from public addresses. To the horror of purists and pedants alike, place names such as St Paul's Square were banned and unceremoniously replaced with an apostrophe-free version: St Pauls Square.

The council's reasoning was that nobody understands apostrophes and their misuse was so common in public signs that they were a hindrance to effective navigation. Anecdotes abounded of ambulance drivers puzzling over how to enter St James's Street into a GPS navigation system while victims of heart attacks, strokes and hit 'n' run drivers passed from this world into the (presumably apostrophe-free) next.

Why the confusion? Part of the reason is that apostrophes are not particularly common in the English language: In French they occur at a rate of more than once per sentence on average. In English, they occur about once in every 20 sentences. So English speakers get less practice.

But the rules governing apostrophes are also more complex in English. In both French and English, apostrophes indicate a missing letter, such as the missing i in that's or the v in e'er. But in English, apostrophes also indicate the possessive (or genitive) case. They are used to show that one noun owns another: St James's Street is the street belonging to St James.

The complexity is compounded because in English, the plural is often formed by adding an s. So the word boys means more than one boy. How then do you form the possessive to indicate, for example, a ball belonging to the boys? Is it the boy's ball or the boys's ball or the boys' ball?

And then there are the exceptions. Pronouns, for example, do not take a possessive apostrophe: you can't say I's ball or me's bat. The truth is that knowing when to use an apostrophe is not always easy.

That may be partly because the rules for using apostrophes are evolving. Today, Odile Piton and Hélène Pignot at the University of Panthéon-Sorbonne in Paris present an analysis of the use of apostrophes in English texts from the 17th century and show that the usage was much simpler in those days.

Their main challenge was how to recognize an apostrophe. Apostrophes are often the same as single quotation marks and are entered on a computer keyboard using the same key. So it's easy to get false positives.

Spotting the absence of an apostrophe where there ought to be one can be tricky, too. They give the example of this sentence: "First, that no other mans errors could draw either hatred, or engagement upon me." The automated analysis missed the absent apostrophe in mans, thinking instead that it was the transitive verb "to man."

What Piton and Pignot have yet to study how the use of the apostrophe changes in time. But they now have the automated analysis tools that should make this possible. That could reveal the forces at work that change our language.

For the moment, Piton and Pignot's conclusion is merely that the world was simpler in the 17th century as far as apostrophes go. They say: "The possessive genitive in 's was not very common yet. The apostrophe mostly marks the omission of letters in a wide range of words and the plural of certain words."

Rather like the road signs in Birmingham.

Ref:arxiv.org/abs/1002.0479: "Mind your p's and q's?": or the Peregrinations of an Apostrophe in 17th Century English

The Urban Dictionary defines an infovore as “A person that has a voracious appetite for information”. This term is pretty popular on the blogosphere these days.
The people who actually coined the term are neuroscientists: Irving Biederman of the University of Southern California in University Park and Edward Vessel of New York University. Their findings show that humans are natural infovores. When the human brain processes information, endorphins are released, giving us a feeling of pleasure.
It is probably not wrong to assume that people who are drawn to a carrier in science have a particularly strong predilection for processing and interpreting information.
Even though I am a theorist, I am fascinated by data, and I love how much data is freely available to the public via the internet. Be it astronomical data via the Sloane Digital Sky Survey which will have a dataset of 230 million celestial objects, or from the Hubble Space Telescope, to mention just two scientific data sources.

I would definitely classify myself as an infovore, and I have a confession to make: I am addicted to the weather forecast. I check the satellite image and the rain radar echos several times a day. I am just thrilled to have access to up to date satellite and radar data. It might sound silly, but when you think about it, it’s actually pretty cool and wouldn’t have been possible 20 years ago. We’re living in a time in which huge amounts of data are being compiled (the LHC alone produces about 1.3GB per second!), a huge wealth for all flavors of science. The challenge is to find ways of effectively extracting useful information from it.

Check out a very cool instance of automated processing of astronomical images which is accessible to everyone: Any picture of the night sky submitted to the pool of the astrometry group on Flickr is run through an engine, which posts a comment to the picture with the astronomical data of the depicted objects, and adds notes directly on the image which identify the visible objects. I think that’s pretty neat!

Apropos of my recent post showing a Hubble image of two asteroids colliding, the website Word Spy just happened to have a funny choice for their word of the day: cosmophobia, "the strong and irrational fear that in the near future the earth will be destroyed by some cosmic event."

Personally, I figured it’s really for people who don’t like vodka, triple sec, cranberry and lime juice all mixed together, which is silly. Unless it’s headed for you at 30 km/sec. Because that’ll give you a pretty wicked hangover.

What’s better than a gorgeously stunning image of a massive cluster surrounded by delicate, wispy nebulosity?

Well, nothing, really. Unless you can use it for SCIENCE!

[Click to gigantisize.]

Purty, ain’t it? That’s NGC 3603, a very large star-forming region in our own Milky Way Galaxy, lying about 20,000 light years away. It can only be seen from the southern hemisphere, which is why the European Southern Observatory folks got this image using the ginormous Very Large Telescope, an 8-meter behemoth in Chile (and actually, Ginormous Telescope would be a cool name).

Not too long ago — no more than a million years, give or take — a lot of the stars forming the central cluster there were born. There are so many that they appear to overlap, but that’s an illusion due to the blurring of the image from the Earth’s atmosphere (and the nature of light itself only allows us to make star images so small).

Lost in that crowd is a star designated NGC 3603 A1, and it is the most massive star to ever have its mass directly measured. It’s actually a binary star, two monsters locked in a gravitational dance, orbiting each other once every 3.77 days — which right away tells you this is a special pair, possessing enough gravity to toss themselves around that rapidly.

Using simple laws of physics discovered by Kepler back in the 1600s, we can measure the masses of each star in the duo. The heftier of the two is a whopping 116 times the mass of the Sun — which is close to the upper limit of what a star can get to without tearing itself apart. The more massive a star, the more luminous it is, and the surface can get so hot that any material there gets blown off… so that sets a lid on how big a star can get. Details vary depending on a lot of factors, but really 116 times the mass of the Sun is about as big as you’ll ever get for a star in our galaxy.

The other star in the binary is no slouch, tipping the scales at 89 solar masses. If it were just sitting out there all by itself it would rate as a phenomenal star, too. But its partner still wins the prize.

And how do I know those stars were born no more than a million years ago? Because massive stars don’t live long, and any beasts like these two live short lives indeed. It won’t be long before they detonate as supernovae, lighting up with a violence and fury that will make each outshine the rest of the stars in our entire galaxy combined!

Not only that, but pretty much every star you see in that cluster is of the massive and luminous classes astronomers call O and B stars, bruisers with enough oomph to explode as supernovae. How many stars do you see in that cluster? Dozens? So think about that: each one of those will become a titanic supernova, wreaking havoc across dozens of light years, sending out blasts of light to outshine galaxies, and throwing out octillions of tons of gas.

Eventually that gas, laced with heavier elements created in the nuclear forge of the supernova blast wave itself, will slam into, merge with, and seed the surrounding gas in the nebula. Compressed beyond its ability to sustain itself, the gas will collapse and form more stars. Some of these may be massive ones which will again repeat the cycle, and some will have lower mass, be fainter, cooler. They may form planets from those heavy elements. It will be a rocky birth, given the environment, but the vagaries of orbital dynamics dictate that eventually those systems will leave the nebula and move out on their own in the Milky Way. And a billion years from now, two, four billion, who knows what creatures may roam the surfaces of any of those worlds.

And will they see more stellar factories dotting the galaxies starscape, and wonder what their own looked like, all those eons ago?

From Eternity to Here addresses the problem of the arrow of time — why is the past different from the future? But Chapter Six is all about time travel, and in particular the interesting version in which you travel backwards in time. Whether it’s possible, what rules it would have to obey, and so on. And now — even though I’m sure there aren’t more than two or three of you out there who haven’t purchased the book already — you can get a sneak peek of part of that chapter. It’s going to be the cover story in the March issue of Discover, and the story is already available online.

And here’s a bit of multimedia bonus: to get the cool exploding-clock image, the intrepid editors worked with Biwa Studios to film high-speed video of exploding clocks, and you can see the whole videos online. They run the events forwards and backwards, just in case your personal arrow of time needs to be calibrated.

One may ask, why is there a chapter about time travel in a book about time’s arrow? Just couldn’t resist the temptation to talk about everything related to “time”? In fact there is a deeper reason. In the real world, the laws of physics may or may not allow for closed timelike curves — physicist-speak for time machines. (Probably not, but we’re not as sure as we could be.) But apart from the difficulty in constructing them, time machines boggle our minds by offering up logical paradoxes — what’s to prevent you from traveling into the past and killing your parents before they met? There is a consistent way to handle these paradoxes, simply by insisting that they never happen. (And we’re still hopeful that the folks at Lost adhere to this principle, regardless of the surface interpretation of last night’s Season Six premiere.)

The reason why that’s hard to swallow is because we can’t imagine anything that stops us from killing our parents, once we grant the existence of time machines. We conceptualize the past and future very differently — the past is settled once and for all, while we can still make choices about what happens in the future. That, of course, is the arrow of time. At the heart of what bothers us about time-travel paradoxes is the difficulty of establishing a uniform arrow of time in a universe where time loops back on itself.

Of course the easy, and probably correct, way out is to simply believe that time machines don’t and can’t exist. But disentangling the demands of logic from the demands of common sense is always a rewarding exercise in its own right.

We are at the stage now where the ability to crank up the intensity and energy of the LHC beams to full power is at hand.  We’re like a toddler that just learned to walk: the urge to run is present and exciting, but the probability of banging our head would be high!

It has been decided through many meetings, and with considerations of experts on the front lines, that the highest, safest energy the beams can be run at without major repairs is 3.5 TeV per beam with an instantaneous luminosity of 2*10³²/cm²/sec. (The LHC was designed for 7 TeV per beam and an intensity of 10³⁴/cm²/sec.)

More intensity means more proton collisions, and more energy means high probability of interesting collisions.  Unfortunately, high intensity and high energy also means high risk of accidents – like the one in Sep 2008.

With that in mind, management decided to balance safety of the machine with the drive to explore and make discoveries.  So, the current plan sets a goal of collecting a specific amount of data, 1 fb^-1, before shutting down for one or two years starting around the beginning of 2012 for repairs and upgrades.

If nature is hiding secrets in areas we now expect them, then this should provide enough data for discovering some of them, or at least allow ruling out some theories – and all without hurting ourselves.

-Mike

On Thursday Davis will be trying a new kind of demonstration: he will spend the entire teaching day — 7 hours — pedaling his bicycle on rollers. The purpose is to give his students a visual lesson in work, power, energy, angular momentum, torque, and other topics.

First, they teleported photons, then atoms and ions. Now one physicist has worked out how to do it with energy, a technique that has profound implications for the future of physics.

In 1993, Charlie Bennett at IBM's Watson Research Center in New York State and a few pals showed how to transmit quantum information from one point in space to another without traversing the intervening space.

The technique relies on the strange quantum phenomenon called entanglement, in which two particles share the same existence. This deep connection means that a measurement on one particle immediately influences the other, even though they are light-years apart. Bennett and company worked out how to exploit this to send information. (The influence between the particles may be immediate, but the process does not violate relativity because some informatiom has to be sent classically at the speed of light.) They called the technique teleportation.

That's not really an overstatement of its potential. Since quantum particles are indistinguishable but for the information they carry, there is no need to transmit them themselves. A much simpler idea is to send the information they contain instead and ensure that there is a ready supply of particles at the other end to take on their identity. Since then, physicists have used these ideas to actually teleport photons, atoms, and ions. And it's not too hard to imagine that molecules and perhaps even viruses could be teleported in the not-too-distant future.

But Masahiro Hotta at Tohoku University in Japan has come up with a much more exotic idea. Why not use the same quantum principles to teleport energy?

Today, building on a number of papers published in the last year, Hotta outlines his idea and its implications. The process of teleportation involves making a measurement on each one an entangled pair of particles. He points out that the measurement on the first particle injects quantum energy into the system. He then shows that by carefully choosing the measurement to do on the second particle, it is possible to extract the original energy.

All this is possible because there are always quantum fluctuations in the energy of any particle. The teleportation process allows you to inject quantum energy at one point in the universe and then exploit quantum energy fluctuations to extract it from another point. Of course, the energy of the system as whole is unchanged.

He gives the example of a string of entangled ions oscillating back and forth in an electric field trap, a bit like Newton's balls. Measuring the state of the first ion injects energy into the system in the form of a phonon, a quantum of oscillation. Hotta says that performing the right kind of measurement on the last ion extracts this energy. Since this can be done at the speed of light (in principle), the phonon doesn't travel across the intermediate ions so there is no heating of these ions. The energy has been transmitted without traveling across the intervening space. That's teleportation.

Just how we might exploit the ability to teleport energy isn't clear yet. Post your suggestions in the comments section if you have any.

But the really exciting stuff is the implications this has for the foundations of physics. Hotta says that his approach gives physicists a way of exploring the relationship between quantum information and quantum energy for the first time.

There is a growing sense that the properties of the universe are best described not by the laws that govern matter but by the laws that govern information. This appears to be true for the quantum world, is certainly true for special relativity, and is currently being explored for general relativity. Having a way to handle energy on the same footing may help to draw these diverse strands together.

Interesting stuff. There's no telling where this kind of thinking might lead.

Ref: arxiv.org/abs/1002.0200: Energy-Entanglement Relation for Quantum Energy Teleportation

Every year, not long after the state of the union address, the administration unveils its budget request to Congress. Then comes the long authorization and appropriations process; in an election year I’d bet that they try hard to have it done before November. The Obama administration’s request came out yesterday, and so it’s time to take a look at how science may fare next year.

Jeffrey Mervis at ScienceInsider over at the AAAS has a nice article summarizing the general picture for science in the budget, including an 8% increase for the National Science Foundation and a smaller 3% boost to the National Institutes of Health. The Office of Science and Technology Policy (headed by the president’s science advisor) has a set of fact sheets on science policy. Check out the one on doubling the science budget – the administration is on track for doing just that by 2017. Will Congress support that?

But, being funded by it, I always start first with the DOE Office of Science. The DOE has a summary document with budget highlights; for the Office of Science the most succinct table shows the breakdown by program and year (click on it for a bigger version):

Overall, the OS is looking at a 4.4% increase over FY2009, not including the stimulus bump in 2009, listed in the column called “recovery”. In a year when the administration wants to freeze discretionary spending, that is not bad for science. It’s clearly coming from savings elsewhere, meaning someone’s program got cut, and those people (and their congressional representatives) will be fighting like crazy to restore it.

Within the OS there are winners and losers as well. Basic Energy Sciences, which covers a host of research in condensed matter including nanotechnology, materials, and multipurpose facilities such as the large light sources, gets the lion’s share of the OS budget, and are slated for a 12% increase. I think this reflects the administration’s desire to foster research in areas that could lead in the near to medium term to new sources of energy. That increase, though, along with increases for advanced computing and bio/environment research, has to come from the other programs in OS, and it appears that fusion energy (-10%) and a line titled “Congressionally Directed Projects” . Now what on earth is that?

Now, I am not a Washington insider by any means, but I don’t recall seeing that designation explicitly in the tables before. I believe, though, that it means projects funded through Congressional earmarks. Are all earmark-funded projects being killed? It certainly appears so…

Within my own field the tea leaves say that the administration is requesting that the Tevatron remain in operation through 2011, support participation in the LHC and work on future upgrades to the experiments, and begin to develop the next big project at Fermilab, so-called “Project X” (which deserves a post all by itself some day). Project X will deliver an ultra-intense beam of protons for neutrino and rare decay experiments, including the Long Baseline Neutrino Experiment proposed for the Deep Underground Science and Engineering Laboratory (DUSEL) in the Homestake Mine in Lead, South Dakota. There is also a substantial appropriation for the Dark Energy Survey; Fermilab is building the camera.

So begins the 2011 budget cycle.

l, too, have a new toy, but considerably more practical. You are looking at an industrial laser, which emits an extraordinary light, unknown in nature. It can project a spot on the moon. Or, at closer range, cut through solid metal. I will show you.

"You do not really understand something unless you can explain it to your grandmother." ~ Albert Einstein

Last week, the Lincoln Near-Earth Asteroid Research (LINEAR) sky survey program, designed to sweep the heavens looking for near-Earth asteroids, spotted something really weird; an elongated streak that looked as if two asteroids had collided. Just days later, Hubble was pointed at the object, and what it saw was really really weird:

[Click to armageddonate.]

This is a false-color image showing the object, called P/2010 A2, in visible light. The long tail of debris is obvious; this is probably dust being blown back by the solar wind, similar to the way a comet’s tail is blown back. What apparently has happened is that two small, previously-undiscovered asteroids collided, impacting with a speed of at least 5 km/sec (and possibly faster). The energy in such a collision is like setting off a nuclear bomb, or actually many nuclear bombs! The asteroids shattered, and much of the debris expanded outward as pulverized dust.

Now, let me just take a moment and say HOLY HALEAKALA WHAT WE’RE SEEING HERE IS THE COLLISION BETWEEN TWO PREVIOUSLY UNDISCOVERED ASTEROIDS THAT EXPLODED LIKE THERMONUCLEAR WEAPONS WHEN THEY IMPACTED!!!

Phew. OK, I feel better. I needed to get that off my chest.

First off, to be clear we’re in no danger from this event. It was really far away (in human terms; 140 million km or 90 million miles — the object’s orbit keeps it farther from the Sun than Mars — so we’re not about to get pummeled with debris. And while the explosion energy was quite large — certainly much larger than any weapon ever detonated on Earth — it wasn’t radioactive, in case you’re worried about that sort of thing. This was a kinetic explosion, caused by a high-speed collision, and not an actual detonation of any kind.

Looking at the image, the bright spot to the left is most likely what’s left of one of the two asteroids, a chunk of rock estimated to be a mere 140 meters (450 feet) across. In the press release they’re not clear about the curved line emanating to the right of the nucleus. It may be — and I’m spitballing here — dust blown back from a stream of chunks, since the tail is broad and appears to originate from that swept curve, and not from the nucleus itself. The other filament perpendicular to the curve is from yet another piece of debris.

Despite how much this looks like a comet, ground-based observations indicate no gas is present, meaning this was from asteroids colliding, not comets, which have significant amounts of ice which turn to gas near the Sun. The collision energy was high enough to produce a lot of gas if any were present. That clinches this being an asteroid impact.

Also, the orbit of the object indicates it’s an asteroid, and it appears to be part of a well-known group of asteroids called the Flora family, which share similar orbital characteristics, and are probably remnants themselves of an ancient breakup of a much larger parent asteroid.

Nothing like this has ever been seen before. Sure, Hubble and about a hundred other telescopes observed the comet Shoemaker-Levy 9 slam in to Jupiter in 1994, but that was different than seeing two asteroids hit. Asteroids are small, and very very far apart on average (don’t believe scenes like that in "Empire Strikes Back"), so a collision like this is extremely rare, and catching it from such a great vantage point rarer still. But we have a lot of eyes on the sky, and the more we watch the more we’ll see.

And we’d better. An object 140 meters across hitting the Earth would, to be technical, suck. Hard. Whatever caused Meteor Crater in Arizona, an impact scar over a kilometer across, was itself probably about 40 meters across. An object like 2010 A2, which is three times the diameter, would have 20 -30 times the mass, and do considerably more damage. I’m glad groups like LINEAR are out there patrolling the skies for such things. We need to learn as much as we can about these asteroids, so that we can prevent the next Meteor Crater from occurring.

"Why three families ? Why the particular symmetry structure ? [...] If the Higgs particle turns out to exist as conventionally described, with a reasonably low mass (say less than 200 GeV) then that closes the Standard Model from a mathematical point of view. It is then quite conceivable that new physics, not contained in the Standard Model, will be way beyond the reach of any accelerator imaginable today. In this case, humanity might never get an answer to the questions posed above."