I finished my first CERN post marvelling at the openness of CERN’s network to the Internet. I though I’d add a few things that I found fun and that are accessible without any kind of authentication.

• First off, the web page you’re usually presented with when going to cern.ch is CERN’s public web page, which is a nice bit of fluff, but not overly useful. There’s a link labeled “CERN users”, which takes you to the page you get when going to cern.ch from within CERN. This is much more informative, including an overview of what’s happening at CERN - seminars, conferences, other announcements.
• The summer student lectures have video and slides online, which is quite nice. For physicists, I recommend Antonio Pich’s Standard Model lecture, especially for its hilarious slides. There’s also an introduction to particle physics for non-physicists and a couple of lectures about CERN’s computing projects.
• Indico is CERN’s conference management system, which has a nice calendar with mouseover popups where you can get at the slides and minutes of the thousands of meetings and conferences that go on.
• Want to see what’s going on in CMS? There’s a page of web cams watching different parts of the detector complex, from the experimental cavern to the parking lot.
• For the more technically minded, here’s a view of the status monitors for CERN’s accelerator complex. If you’d like to make sense of the blinkenlights, this page and the linked FAQ are pretty useful. More operational fun: Since CERN’s accelerator complex is rather old, parts of the status information are still transmitted via CCTV channels and, of all things, teletext - the CERN teletext server is a gateway for those of use using more modern receiver equipment.

I’m still amazed that all this stuff is public. Yes, the actual discussions surrounding new discoveries will be a lot more secretive, but I still like the idea that hundreds of millions of people can watch the SPS go through various stages of a power failure for their Sunday afternoon entertainment…

Update: Oh, the LHC vistar is a lot more interesting this weekend, as you can watch the progress of the second injection test.

19:00 Alternate injections into sector 78 and sector 23 which is pretty blooming amazing.

:)

At the end of July, I had to leave my previous lodgings in Ornex and move to Genève proper, where I now inhabit an apartement on the fifth floor of la Cité Universitaire with two colleagues. The move caught us ill-prepared in a number of crucial ways, and so the first evening went rather depressingly - the kitchen proved to be spacious, but rather empty (Three spoons, three forks, three butter knives, three plates, three glasses, three cups. One pan, one pot.), and so the first dinner went badly (our only source of salt being a can of anchovis).

Much worse, it turns out that although there is wireless internet avaiable, the charges for short stays are rather steep - two weeks would have been 70 CHF for an unexplained amount of connectivity, and probably limited to one PC. The other available WLAN is provided by the university, but they use MAC filters and a HTTPS secured login form to keep out guests. While pondering this depressing state of things, we chanced upon a third source of network connectivity, named ‘((o)) ville de geneve’ - which turns out to be Genève’s municipal WLAN, available in select spots around the city. It seems that our location was high enough to get stray signal from a stadium a couple of hundred meters away. Sadly, the connection was weak and required users to sit in exactly the right spot in our kitchen’s window bay or lean out of the window with the laptop. To rectify this untenable situation, we semi-seriously acquired a can of Pringles on our Friday shopping trip, and I went to town today in search of a PCMCIA card with an external antenna plug. It was impossible to obtain such a thing, but while browsing available WLAN adapters, I got the much better idea to simply take a USB adapter and build it directly into the antenna… I hopped over to the local Starbucks and verified that of course there was nothing original to that idea and people had done it before all over the Internets, using materials like a strainer, wok lids or fire extinguishers.

I bought a D-Link DWL-G122 USB plug and brought it home. Initially, we hoped to get enough signal advantage from just hanging the USB plug out of the window by its cable, but apparently its antenna is so much smaller that it compensated for the better reception. Some interesting results from that: reflection DOES make a difference - holding the adapter in front of a closed metal shutter or mounting it in our cooking pan definitely increased the signal strength. None of these methods were really practicable, though, so we decided to go the classical Yagi route. Eating the Pringles was pretty hard, but the results are worth it… We now have comfortable signal strength and the network is reexported around the entire apartment via the internal WLAN card in the attached computer, and the setup is even quite stable thanks to the fact that one of my roommates lent his tripod to our noble enterprise.

(Yes, the USB adapter and the Pringles cost just as much as just buying the Internet access would have, but would that have been as much fun?)

Update: On revisiting Edificom’s pricing information, I see that we actually managed to save some money (70 vs 115 CHF) AND gained the fun. Win!

That LSAG report? It’s just propaganda for outsiders. In case anything goes REALLY wrong, somebody has to run down 94 meters of stairs (because the elevators are so damn slow) and manually save the world:

In other news, I managed to pull my first all-nighter at CERN (due to the fact that I didn’t want to bike home in the rain), and I’m looking forward to tomorrow’s Bastille Day. My French is still miles away from being sufficient for singing along la Marseillaise, but I really like the spirit of it… To get a feeling, read the translated lyrics while Mirreile Mathieu sings it in a video that was probably shot by Leni Riefenstahl’s French twin.

Qu’un sang impur abreuve nos sillons…

I’m at CERN for the next couple of weeks, working for HEPHY on the trigger subsystem for CMS.

The first couple of days have been pretty overwhelming - the amount of bureaucracy at CERN is truly scary, there’s lots of things to learn, and life in France can be pretty challenging for non-francophone people (So far, the longest truly successful conversation took place yesterday morning at la boulangerie in town, where I managed to purchase two baguettes. Tomorrow, I will try to progress to two baguettes and three croissants…). Great fun so far, and I even got to see CMS up close in semi-disassembled state. I can confirm that it’s pretty impressive, especially when one of the kiloton segments slowly starts to move while you’re watching. The Wikipedia picture doesn’t really do it justice because it only contains the structural elements, while the final setup is much more complex. Unfortunately, my compact camera, the bad lighting and the general excitement conspired to make all my pictures ill-focussed, but let me repeat that it’s impressive. Here’s the best of a sorry lot, complete with puny human for scale in the center right.

Another amazing thing about CERN is that pretty much everything that they do ends up on the public web. All our schedules, documents and even source code are on Google. While compiling a piece of the trigger software today, I was foiled by a missing header file. Googling it gave me the change from the CVS (Yes. In 2008. Amazing, but not in a good way…) web interface where it was deleted. Every PC gets public IP addresses. I really wonder how the IT people keep the whole mess alive with tons of temporary people always arriving or leaving…

Okay, so Debian shipped broken OpenSSL for about two years. The advisory is scarce on details (after dealing with crypto literature for a while, you learn to think of “weak RNG” as “well, someone who had perfectly observed twenty billion random numbers I’ve generated could maybe have a fifty-one percent ability to guess the next bit”, which has about zero implications for real world security), but Ben Laurie explains the full story. Apparently, the Debian package maintainer noticed that OpenSSL used uninitialized memory to supply entropy to the RNG, but “fixed” it by disabling the function to add ANY entropy to the pool. This, and the fact that the ssh-vulnkeys utility shipped with the OpenSSH upgrade checks for vulnerable keys by comparing keys to an apparently exhaustive list of some 200000 keys, make it look rather scary. If I understand this correctly, it looks exploitable enough to turn into a nasty real-world problem for some time to come.

On the up side, I really like the engineering of the Debian fix - the new packages refuse to run with compromised keys (and automatically generate safe ones on installation), and upgraded servers refuse logins from unsafe client keys. This eliminates the worst of all the horrors where outdated authorized_keys entries for the unsafe keys would litter the Internets for decades to come, providing rogue access for any idiot with a copy of the master key list…

Update: Ah, the exploit is here.

For Christmas 1984, I wanted nothing so much as an accordeon. I had deposited the wish via the usual channels (a letter on my window sill that vanished some time later, and constant nagging of everyone who would listen) during the season time, and since I was the only child in my age bracket for all of the extended family, I was rather confident that an accordeon would materialize under the tree through whatever mechanism involved.

After the preliminaries had been taken care of on the great day, I settled in front of a pile of packages and methodically started tearing them open, discovering that their contents were “not an accordeon” and moving on to the next item. While the people around me slowly realized that it would probably have made everyone happier if they had just given me what I had wished for instead of all the other stuff, I clung to my hope fiercely, expecting the accordeon to magically hide in packages the size of cigarette packs. When it dawned on me that there WAS no accordeon, it was a very sad Christmas.

Well, at least I can blame my family for the fact that I’m just a useless physics bum now, and not a great artist (via fefe). There.

As a result of an oversupply of holidays (two weeks of university between the start of the semester and Easter?), I have developed an increased interest in cooking. While reception of the products has been mixed (Why do so few people seem to appreciate the beauty of packaging food into slimy balls?), I have found cooking a much better source of light conversation than my usual pastimes. One recent instance yielded a recommendation of this book, which, at long last, brings us to the actual meat of this post: British home cookery legend Delia Smith apparently wrote a similarly titled book, How to Cheat at Cooking, which caused a lot of controversy over its use of ingredients like tinned mince meat or frozen mashed potatoes. The Guardian put the recipes to the test, and the result is hilarious.

It’s worth a read just for the quotes, and I felt a distinctive note of Fawlty Towers in this paragraph:

In the kitchen, maestro Zilli and the chef at his restaurant Zilli Fish, Pasquale Amico, are swearing over a new and controversial recipe book. Actually, only Aldo is swearing. Pasquale is just getting on with it, albeit bearing a look of slightly pained incomprehension.

It only gets better:

“It’s a crime against aubergines. They’re such beautiful vegetables, and to see them treated like this. It’s appalling.”

(via molekularkueche)

But still… CDE? Fvwm? Hard to tell because these goddamn Unix people keep imitating each other’s window decorations…

Another take on my perennial favourite social convention, the dress code: Signalling (on Cosmic Variance).

This instance of the pro-dress-code argument is so lame I can hardly be bothered to discuss it (”Everyone should dress so that they wouldn’t embarrass my mother”), but I welcome people making good fun out of it. So, like I already said back in the day, dressing up is about signalling status - but why do we have to drag aesthetics into this? Can’t we simply wear t-shirts that show our current bank balance, grade average, or pictures of our model-grade SOs? Why the silken suicide utility? I might add that signalling status is actually counterproductive in academia, since discussions are not supposed to be guided by “the guy with the necktie said it, so it must be true”-type decisions. In the long run, I hope that the belief in suit == authority will fade away, helped along by the tireless work of Chinese tailors flooding the market with cheap high quality evening dress. Still, I’m not holding my breath (nor am I as religious about the “don’t dress to impress” rule in real life, being the unprincipled cynic that I am).

While preparing a chemistry presentation, I came across a book describing research chemists by giving each person two pages - one describing their research interests and results, and one for a recipe. Given that I was looking for something different, the only thing that stuck with me was the exceptional simplicity of the recipe for dulce de leche (immediately reminding me of a dot-com era business plan):

1. Put a can of condensed milk (the sweetened kind!) into boiling water.
2. Boil for two to three hours.
3. ???
4. Profit!

The ??? part is apparently called a Maillard reaction and magically creates caramelly goodness (the linked Wikipedia article is slightly weird since it claims that Maillard reactions are only significant at temperatures above the boiling point of water, citing a reference that makes no such claims). Since my condensed milk came in a tube instead of a can, I was a bit nervous about pressure issues, but it seems that Nestlé’s packaging engineers overspecified enough to make it work.

Two-and-a-half hours of boiling got me a distinctly unrunny consistency, which tends to stay in shape against gravity’s meager coupling constant, even when poured on ice cream or such (which, due to certain associations most people have with piles of brown sausagy stuff, is not so great for the enterprising host). Maybe I’ll give it a little less time on the next run.