Tuesday 16 December 2014

'Tis the Season!

Christmas lights in Uppsala
Lit up trees along Uppsala's river, Fyrisån. 
So it's almost that time again: Christmas break! It's looking Christmas-y here, with beautiful Christmas lights and even the occasional dusting of snow (or at least frost). This coming Friday I'll be heading back to Amsterdam to visit family and friends over the holidays. I had my only exam of the term yesterday, and tomorrow is my last lecture before my break begins.

Scheduling of lectures and exams at Uppsala University is... interesting. As in, totally erratic. I've been led to believe that this is common in Sweden, but I don't know for sure. In any case, the year is basically broken down into 2 semesters (Autumn and Spring), each containing 2 periods. The exact dates are available online at the Academic Calendar page. This page also contains one of the scarier pieces of text that I encountered while I was applying to Uppsala:

Wednesday 3 December 2014

New kid on the blog

Hi!

My name is John and I've recently been asked to take over this blog. I'll be writing about life in Sweden, Uppsala University, and tossing some physics in every now and again for good measure. But first of all, an introduction: who is John?

Me at Nikhef
Me at Nikhef, the Dutch National Institute for
 Subatomic Physics, which was right across the street
from where I lived in Amsterdam
I'm a first year masters student in physics, following the theoretical physics track. I was born in Scotland, but I moved around quite a lot as a child before finally settling down (for a while) in Calgary, Canada. Since this was where I lived longest, had practically all of my teenage years, and picked up my accent, if you ask me I'll say I'm Canadian (and I've got the passport to prove it). My bachelors degree is from Amsterdam University College (AUC) in the Netherlands, where I lived and studied for three years.

Tuesday 11 February 2014

It came, it went, it didn't really conquer...

Lame Latin puns aside, the snow did actually come for a few weeks and it was amaaaazing! Well, mostly. Most days were a balmy -5 but there were a few scary nights where the temperature plummeted to -15, and that's not fun anymore.. (those days it feels like you're wearing a t-shirt under your third layer and winter jacket.. brr).. However, I did manage to convince my wife to go on a pulka with me (a pulka being a small, fairly cheap and crappy sledge that children and easily amused adults adore). This is exactly the one we used, 100 SEK in Clas Ohlson: http://www.intersport.se/Root/inRiver%20Resources/135426682783768214.png

For those not in the know, Sunnerstabacken is where it's at, where all the cool kids go (literally, our combined ages were larger than the cumulative sum of all kids) and the funny thing is, all of them, from the youngest (like 2) to the oldest (like 2 + x, where x is an integer in the bounded interval [0, x'], and x' is some constant given by the subjective definition of youth ... in reality, like 12 or something...), were utterly fearless. Maybe it's the fact that their lower mass equates to lower maximum acceleration, maybe it's the fact that children think themselves indestructible, I don't know... But one thing is certain, we certainly weren't. Those things go fast! But that's the best part. Or even better is hanging your legs out as brakes and not realising that despite being effective, it also sprays a ridiculous amount of snow in your face, and as most are well aware, snow is known as a "cold substance", and cold things hurt my face... I have some pictures on my phone, I look hilarious and very very cold. So we did that for an hour or two, until of course, we took it too far and went on the big and scary and icy slope and nearly killed ourselves (I saw nothing the whole way down and was mid-air more than once... Ana broke her back for a few days... Overall, it was awesome...Seriously.)

But then it left :( About a week or two ago, it gradually became milder and slushier and greyer.. (I've always wondered why during winter the weather is, on average, better when there's regular snow then when there isn't... Maybe something to do with the conditions that give snow are also favourable to clear skies and calm weather? Not always, of course, but I did notice a lot of the snowy days were also sunny... Now it's just wet and grey and depressing... I feel like I'm back in Ireland, but with dearer beers :P)

But enough about snow, let me talk a little about a project I just started in the Astrophysics division. It's regarding the Sloan Digital Sky Survey (SDSS), a "major multi-filter imaging and spectroscopic redshift survey" (Wikipedia). Basically, they take a bunch of measurements of many different quantities interesting and useful for astronomers/astrophysicists/etc, and catalogue them in a massive database which can be accessed freely (there's even a bunch of tutorials on the site to get you up and running). Every now and then, they come out with a new data release which usually provides many more objects than the previous one. The current release is 10 but we're currently using 7, meaning all our graphs, results, and so on, could look a lot better and be a lot more informative if we were using 10.

However, the database is queried using SQL and unfortunately they have a tendency to change the names of all the objects in the database from release to release (meaning to get the same thing in two different releases can have completely different code). So my task is to determine the new code for each release and compare the results from release to release. Do I get the same results as everyone else in release 7? Do I get similar (but "better") results in 10? And so far, I've had really great success, which makes me very happy. I hadn't used SQL before but I really enjoy it now. The whole interface is a bit of a mess (some releases use different sites, servers, many things are duplicated in "old version/new version" fashion, which is a little frustrating) and the SkyServer for Data Release 7 (DR7) went down yesterday, forcing me to use a different separate server just for DR7 and below. However, that one needed me to make a new account to access (though it looks almost identical) but became upset when my queries returned too many results (I expected around 20,000 -"too many" in this context means around 20 million....). So my account ran out of storage space but wouldn't let me delete the database (it was very upset). So I had to create another account (bear in mind, these all required different email addresses...) and finally got everything working perfectly :)

Except not. Why? Because while the general trend has been DR7 = one set of code, and DR8-DR10 = equals another set, for these particular sets of queries, DR9 and 10 had the same code but DR8 was different. Completely different. So different we couldn't get it to work and have lost faith that it can be done in DR8.

But having it in the newest release is pretty good, right? Yes, of course, except (there's always an except, isn't there?!) what we want to do in the previous releases can't conveniently be down in DR10  - the entire underlying structure has been changed. We wanted to deal with quasars and low redshift galaxies, and instead everything is mixed together so our results are sort of like this:

DR7: 13 000 objects (galaxies, low redshift quasars)
DR8: ????
DR9: 17 000 objects (niiice, same order of magnitude, a few more, very very good)
DR10: 600 000 objects (wtf? That makes no sense.)

But we're working on it and we're well ahead of schedule, so that's great to hear :) Also, it's my first time being "promoted" to a full-fledged access-card wielder, and I'm so happy. I get to sit in a fancy department which has a ridiculously fancy espresso maker and coffee bean grinder and free fruit and a fika data on Monday's and every second Thursday and "AstroPub" on Fridays (lecturers, researchers, students all meet in a random pub for a beer to relax after the week).

I tell ya, "easily-impressed" doesn't even cut it with me ;)

So that's the story so far.. Will update more how this project turns out, it's becoming very exciting now that this underlying work is mostly finished. Now the "interesting" stuff appears (though I'm too damn curious for my own good that I already found this stuff extremely interesting).

Oh wait! I almost forgot. I saw the TandemLaboratoriet last week, Uppsala's very own particle accelerator. Really cool because it's the one and only I've ever been so close to! (I did go to CERN a few years ago but they don't let us mere mortals near the actual machine itself... thank god, actually!). I met some lovely researchers and prospective Master's students, while being fed and given far too much coffee, an all-in-all, productive day :) I also saw a presentation by a previous PhD. student, now working in Stockholm University, who is working on Sweden's first and only SETI project (SETI being the Search for Extra-Terrestrial Life, like Star Trek, sort-of, but we stay here and nothing has happened so far...). It's a tough field to work in by the sounds of it, very difficult to get papers published or be taken seriously, which I think is really unfair :( Definitely one of the fields that if (or when?) they discover something, everyone will say "Well, don't I feel like a jerk now..."

Good luck SETI PEOPLE!

P.S. A bunch of interesting lecturers are happening on Thursday & Friday, people should go:
http://www.uu.se/en/media/news/article/?id=3192&area=2,16&typ=artikel&na=&lang=en

Sunday 5 January 2014

The New Year Madness Has Begun!

As always, the thrill and excitement of the New Year is upon us once again, where promises are made and broken (often simultaneously!) and the gym is packed with hopes and long, long queues. At least it forces the more "modern" of us out into the wide world of nature where we may run amongst the trees and...etc.... Yes :) Though I would actually love to do so if there happened to be snow here. As miraculous as it seems to me, there is no snow this winter in Uppsala! (okay, there was a little that lasted for a short two days but that doesn't count).

But why, you ask? I have no idea. I keep Googling it, hoping to see the words "Heavily Thunderous, Incapacitatingly Voluminous & Copiously Covering Amount of Blizzard-like Snow Approaches Uppsala for the Forseeable Future (And It Will Be Fantastic)" appear, but I see nothing. Either I'm the only one who cares that winter isn't freezing this year or Googling no snow uppsala :( aren't suitable keywords.

EDIT: (I'm actually editing this while I'm writing this, but my search has turned up GOOD news!) This Friday, the 10th, it's expected to snow. The actual numbers I can't confirm because I'm certain meteorologists just make this stuff up (that's not true, I just don't understand meteorology very well and I'd rather blame them, than my ignorance, for this lack of snow... Human nature, eh?) Anyway, Google predicts -11 C that night... Mmm... Delicious. Other sites say -2 or -4 with some light snow... which is OKAY because it's always colder than what they say. Will definitely take pictures to celebrate :) It would have been nice to have it for Christmas but oh well, better late than never! 

Now that the mandatory weather discussion is out of the way, what else has been happening? Well, neither Peter Higgs nor François Englert would come to Uppsala for the annual Nobel Lectures due to "prior engagements" and "senility"(http://www.unt.se/uppsala/nobelpristagare-forelaser-i-uppsala-2743775.aspx). Disappointing, I know... For those who don't know, those gentlemen were awarded the prize for their work contributing to the mechanism by which particles acquire mass (previously, nobody knew. The theory "predicted" that particles shouldn't have any mass because it would violate certain symmetry properties needed in the theory for consistency. They found a way of keeping the symmetry in general but "breaking" it temporarily such that a field, called a Higgs field, interacts with itself and other fields to gives particles mass (that's a sloppy explanation but I'm not talented enough to explain it without mathematical concepts like Lagrangians and Gauge Symmetries). It would have been really cool to hear a description of it from the horse's mouth.)

I would also like to take a short moment to congratulate my good friend Andrea Palaia for recently (14th December) acquiring his Ph.D in Accelerator Physics (originally titled Who Screwed Up my Beam?). Now that he is onto bigger and better things, I wish him all the best in the future :)

Oh, one very cool thing that is a consequence of cold weather is that there's an ice skating race from Uppsala to Stockholm (the course is supposedly 80 km long!) called Vikingarännet. There's even a shorter "family friendly" version that is only 15 km long which I'm considering very heavily of doing, despite the fact I've only done ice skating once in my life, 12 years ago, and that memory is vague at best. But I have done quite a bit of rollerblading (a mere 8 years ago) and ice is just the new tarmac... Right?

Anyway, we'll see how cheap blocket can sell smelly old ice skates :P The site is here for anyone who is interested... http://vikingarannet.com/en/training-and-equipment/equipment/ That will be my New Year's Resolution - trick my friends into skating 15 km! Misery deserves company :P

Till next time, Gott Nytt År! :)