Teake's blog

Affine root systems

2010-03-29T17:39:00.000+02:00

Currently I'm working on my PhD thesis. It isn't finished yet, but I decided the following images were worth a sneak peak:

Besides looking nice, the pictures actually convey some information. They're so-called Hasse diagrams of the root systems of a few affine Lie algebras. From left to right we have the following affine algebras: (a) A1+, (b) C2+, (c) D4+, (d) A8+, (e) D7+, and (f) E7+. But luckily you don't need to fully understand the mathematical background, which is admittedly quite complicated, to enjoy their beauty.

Matching fonts in Keynote and LaTeX

2010-02-16T21:36:00.000+01:00

LaTeX is great if you want to typeset documents with lots of mathematics in them, but what if you want to make presentations with lots of math? Sure, there are LaTeX packages like Beamer with which you can straightforwardly make decent looking presentations using nothing but LaTeX. But none of those packages lets you easily control where items end up on a page, make subtle changes to overall lay-out, or add some motion to your slides.

Keynote does all of those things, and a bit more. Here's for example a slide of presentation I gave some time ago:

The things in the image are all created within Keynote (not in a separate drawing program like Adobe Illustrator), and some of them are even animated. This is simply impossible to do solely with LaTeX, and that's why I've been using Keynote for quite some time now for all my presentations.

However, there was always something annoying me: the fonts in formulae I got from LaTeXiT (a small program that lets you insert LaTeX formula in Keynote) didn't match the font over the overall presentation. And if you're a typesetting nerd like me, that's pretty annoying. Luckily, I found a solution. Here's an example with both type of fonts:

The difference is subtle, but certainly noticable. The greek letters haven't changed, but the others are in the same font in the second equation. Here is how you change fonts:

First, go to the LaTeXiT preferences, and change the default configuration to use xelatex instead of pdflatex:
Next, add the following to the LaTeXiT preamble:

\usepackage{mathspec}
\usepackage{xunicode}
\usepackage{xltxtra}
\setmainfont{Gill Sans}
\setmathsfont(Digits,Latin,Greek){Gill Sans}

Be sure to change the "Gill Sans" to match whatever font you're using in Keynote.

And that's it! After restarting LaTeXiT, all new equations you'll typeset will be in the correct font. Enjoy!

End of the year lists

2010-01-03T15:15:00.005+01:00

2009 is behind us, which can only mean one thing: endless amounts of end-of-the-year-lists! Around this time of the year every respectable music website or blogger will produce his or her list of best albums, best singles, and whatnot. For example, have a look at the lists of Pitchfork, Paste, and Kindamuzik (Dutch). Having compiled my list for the Vera poll, it's a small effort to also put it here. So here are my two cents for 2009:

10. Built To Spill - There is no enemy

MP3: Hindsight

Myspace

9. Throw Me The Statue - Createresque

MP3: Ancestors

Myspace

8. Wake The President - You can't change that boy
Myspace

7. Jay Reatard - Watch me fall

MP3: Wounded

Myspace

6. The Pains Of Being Pure At Heat - s/t

MP3: Young adult friction

Myspace

5. Sunset Rubdown - Dragonslayer

MP3: Idiot Heart

Myspace

4. Phoenix - Wolfgang Amadeus Phoenix

MP3: 1901

Myspace

3. The Maccabees - Wall of arms

MP3: No kind words

Myspace

2. Dan Auerbach - Keep it hid

MP3: Trouble weighs a ton

Myspace

1. Bill Callahan - Sometimes I wish we were an eagle

MP3: Eid Ma Clack Shaw

Myspace

Mac free software list

2009-11-01T18:11:00.001+01:00

Having updated to Snow Leopard this weekend, I once more downloaded and installed the latest version of all the free applications I use. Almost all of them were compatible with Snow Leopard, a thing I checked beforehand for only a few of them. Here's a careful selection of the apps I couldn't live without:

Internet related:

Adium
The multi-protocol instant messaging client for the Mac. Handy if you have MSN, ICQ, and Google Talk accounts (like me).
GlimmerBlocker
The only adblocker for Safari that isn't implemented as a hack -- this one is actually a proxy that filters out the stuff you don't want to see.
Transmission
Simply the best torrent client for OS X.
Google Notifier + Google + Growl
A menu bar app that notifies you when there's new mail in you Gmail inbox. The Google + Growl utility makes sure the notifications are Growl compliant.

LaTeX:

BasicTex
A TeX distribution that's small (54mb) but still has all you need.
LaTeXiT
Unmissable app if you quickly want to typeset formulas and paste them into, say, Keynote.
TeXlipse
A plugin for Eclipse that turns it into one of the most powerful LaTeX editors around.

System tools:

Growl
A notification system for Mac OS X. Many programs are capable of using it, and it's a functionality that's lacking by default in OS X.
USB Overdrive
The default mouse acceleration is really crappy on OS X. USB Overdrive lets you change it according to your own tastes.
CDto
CDto adds a button to Finder that opens a Terminal window and changes its active directory to the Finder directory.

Media:

Plex
Plex is a home theatre app that is much more versatile than Front Row. Amongst other things, it can pull content directly from the internet to your TV.
Perian
Perian adds playback support to QuickTime for a whole range of media format.
Flip4Mac
Adds WMV support to QuickTime.
ScrobblePod
If you've got a Last.FM account, this little app is for you. It scrobbles all your plays in iTunes.

Other:

Jin
Jin is the only chess client that runs on a Mac and supports the Free Internet Chess Server. So if you're a cheap bastard like me and enjoy a game of chess, Jin is the way to go.

Symmetry in and of nature

2009-10-21T16:10:00.000+02:00

In part three of "What on earth has Teake been doing for the last four years?" I'll talk a little on how symmetry appears in nature. When considering this subject, it seems natural to think of symmetric things that appear in nature. Snowflakes, like the one above, are good examples, but also flowers, the wings of butterflies, and sea stars (to name a few) all show some form of symmetry. They fall into the category "things in nature that look kind of symmetric", but in fact have little or nothing to do with the physicist's concept of the symmetry of nature.

One definition of symmetry in physics is as follows: the symmetries of nature are those transformations that do not change the laws of physics. To illustrate this concept, have a look at the following four clocks:

The first clock obviously satisfies the laws of physics. We now apply two different transformations, namely a mirror operation and a time reversal operation. Both give a clock that is distinct from the original one -- you can see the dial moving in the opposite direction. So the clock is not invariant under these transformations, and thus they are not symmetries of the clock. However, there's nothing physically wrong with a clock running in the opposite direction, apart from the fact that it's broken. Therefore parity (a fancy word for a mirror operation) and time reversal are symmetries of the laws of physics of this particular system. In general parity and time reversal are broken, but that's another story.

As a side note, you can see that the combined actions of parity (C) and time reversal (T) do leave the clock invariant, so CT is a symmetry of the clock.

This concept of symmetry is quite powerful. For instance, Special Relativity can be derived by demanding that the laws of physics are invariant under translations, rotations, and boosts (which together make the Poincaré group). Modern physics is to a large extent build on similar considerations of symmetry. So the study of group theory is not just a nice mathematical exercise; it actually has some useful applications throughout the field of physics. In the upcoming blogposts on "What on earth has Teake been doing for the last four years?" I'll try to explain how I applied some fancy group theory to even fancier things like supergravity. Stay tuned!

Band rebus

2009-10-20T22:27:00.004+02:00

Can you guess what bands the images below are supposed to represent? The answers can be found after the break!

In case you're wondering, I made these images for a popquiz I held with some friends. It was pretty fun, not in the least because of the Lego album covers we also put in.
Anyway, the answers are ... :

Bishop Allen
Buffalo Tom
Claw Boys Claw
The Magic Numbers

More symmetry: continuous groups

2009-10-17T17:29:00.002+02:00

In my previous post on "What on earth has Teake been doing for the last four years?" I tried to explain the concepts of symmetry and groups. Today we're going on step beyond, and see how they are related to algebras. Hold tight! It's going to be a bumpy ride ...

Let's first start of with the triangle. As we saw in the previous post it only had six distinct symmetries, and these symmetries formed a group. It's a discrete group because there are only a finite number of symmetries, and thus a finite number of elements in that group.
If you want objects with bigger symmetry, all you have to is increase the number of sides of your polygon. Here's for example the pentagon:

From now on we ignore the reflection symmetries and focus only on the rotational ones. It's easy to see the pentagon has six symmetries: rotations over 0˚, 72˚, 144˚, 216˚, and 288˚ all leave it invariant.

When we move up to the hendecagon (the 11-sided regular polygon), it will come as no surprise that the thing has 12 distinct rotational symmetries. But what happens if we crank the number of sides up to infinity? Then our polygon become a circle:

You can rotate it over any angle, and it remains the same. This means it has an infinite amount of symmetry! The mathematical object that describes these symmetries is still a group, but no longer a discrete (finite) one. The symmetry group of the circle is continuous. The reason why we call it continuous is because you can smoothly get from one rotation to another one by continuously applying infinitessimal (i.e. very small) rotations. Another way of phrasing this is to say that every angle between e.g. 72˚ and 144˚ corresponds to a symmetry. This was not so for the pentagon: in that case there are 'gaps' between the rotations. That's why that kind of symmetry is called discrete.

Continuous groups are known as Lie groups (pronounced as "lee"; they're named after Sophus Lie). They contain an infinite amount of elements. But because they're continuous we can parametrize the elements in one or more parameters. For the circle we can write any rotation over an angle θ as R(θ) as

This is just the rotation matrix in two dimensions. If R(θ) is still a group element, it should satisfy the group multiplication rule: R(θ₁) • R(θ₂) = R(θ₁ + θ₂). Or in plain English: the result of two succesive rotations over angles θ₁ and θ₂ should give a new rotation over an angle θ₁ + θ₂. Sure enough, if we brush up on our linear algebra and trigonometry, we find that

So group multiplication is indeed satisfied.
The above parametrization makes for easier bookkeeping of the infinite amount of group elements. But things can be simplified even further! Because the parametrization is continuous, we can take the derivative of R(θ) with respect to θ:

The magic happens when you consider the value of dR(θ)/dθ at zero angle, θ = 0 :

which we call T, for short. This thing is independent of the angle θ. What's more, you can recover all the rotations by simply exponentiating T:

We say that T generates the symmetry group of the circle. In proper mathematical lingo, it is called a generator. This single object captures all the important properties of the infinite symmetry group (well, almost all, but we'll not go into that right now). The bookkeeping now becomes very simply: we can just focus on the generator T, instead of the infinite amount of group elements.

You can show that for more complicated groups (e.g. the symmetry group of the sphere) the above simplification also holds. All the group elements can be led back to a finite number of generators (in the generic case there is more than one generator). These generators no longer are elements of a group. Instead, they form what is known as Lie algebra. But more on that in one of the upcoming episodes of "What on earth has Teake been doing for the last four years?"!

Quarterly music round-up

2009-10-03T16:57:00.000+02:00

September is behind us, and so are August and July. Time for a quarter-annual update on the stuff I listen to! Luckily Last.FM is not only useful for keeping track of concerts (as I wrote about earlier), but it also keeps track of your listening habits. The graph above is for example a visualization of my listening history over the last three months, made with the tool LastGraph. Last.FM itself produces plain text lists, like the top albums you've listened to. Here are mine:

The Maccabees - Wall of arms
Throw me the statue - Creaturesque
Sunset Rubdown - Dragonslayer
Bill Callahan - Sometimes I wish we were an eagle
The Dodos - Time to die
Phoenix - Wolfgang Amadeus Phoenix
Dan Auerbach - Keep it hid
The National - Boxer
The Maccabees - Colour it in
Jay Reatard - Watch me fall

Almost all are of this year (save no. 8 & 9), so there's a reasonable chance they will make it to my end-of-the-year list. But for that we'll have to wait another three months.

Symmetry

2009-09-29T21:17:00.004+02:00

This is the first post of what eventually should become the "What on earth has Teake been doing for the last four years?"-series. Brace yourself: it's about maths and physics. Run while you still can!

I'll try to keep things simple by starting of with a concept that is as mundane as it is fascinating: symmetry. Not only makes it our world round, but it’s also what makes it go round. From the perfect circular wheels on our bikes and cars that deliver an enjoyable ride, to the error-correction protocols that keep e-mails from turning into junk; it’s literally all around us.

So what is symmetry exactly? A symmetry is an action on an object that, once you’re done performing it, does not change that object. It's a somewhat abstract definition, but take for example the triangle, which has 6 symmetries. There are two different rotations (over 120˚ and 240˚), three reflections, and finally the action of doing nothing at all (yes, that's also a symmetry). You can try them out in the following applet. Clicking on the arrows causes the triangle to rotate and reflect.

This is all pretty straightforward, right? But things start to get interesting we you keep track of the effect of the different rotations and reflections. Let's paint the corners so we can see where they end up:

One thing you'll notice is that doing twice a clockwise rotation is equal to doing one counter-clockwise rotation. The same is true for any other combination of actions -- it will always yield the net effect of one single reflection or rotation. It might also happen that the triangle ends up in the original configuration, but remember that doing nothing is also a symmetry.

The combined actions describe what mathematicians call a group. A group is a set of elements plus a rule of multiplying those elements. Let's call the set G and the multiplication rule "•". Then the precise definition of a group (in which a, b are elements of the set G) is the validity of the following four statements:

Closure.
The result of the operation a • b is also in G.
Identity element.
There exists an element 1 in G, such that for all elements a in G, the equation 1 • a = a • 1 = a holds.
Inverse element.
There exists an element a^-1 in G such that a • a^-1 = a^-1 • a = 1.
Associativity.
The equation (a • b) • c = a • (b • c) holds.

These four set of rules are called the group axioms. They might sound a bit abstract, but in fact, they're not. Let's have a look at our triangle again.

The symmetry actions are labeled as follows:

1: identity element ("doing nothing at all").
y: counter-clockwise rotation by 120˚.
p: clockwise rotation by 120˚.
R: reflection in the top vertex.
G: reflection in the lower-right vertex.
B: reflection in the lower-left vertex.

We already noticed that the closure axiom holds. The existence of the identity element is also pretty obvious. What about the identity axiom? This indeed also holds: every action has an inverse. The reflections are their own inverse, whereas the rotations are each other's. The last thing to check is associativity. It's a bit harder to verify, but believe me, it holds too.

Just for completeness sake, here's one last version of the triangle applet. This one includes the group multiplication table, which keeps track of what happens when you first do the action in the first row, followed by the action in the first column. (If you didn't believe me on the validity of associativity you can use this table to check it.)

What I've shown you so far is that the symmetries of the triangle can be described in terms of the mathematical concept of a group. The importance of group theory lies in the fact that any symmetry you can think of can be described as a group, and that conversely all groups describe a symmetry.

By now the answer to the question "What on earth has Teake been doing for the last four years?" will hardly come as a surprise: it's group theory. More on that in part two of this series!

Last.FM + Google = Convenience

2009-09-25T13:33:00.002+02:00

If you're into music and computers, you're probably aware of Last.FM. It's a social music website that "recommends music, videos and concerts based on what you listen to." For the price of giving up a little privacy to the folks at Last.FM (namely the music you listen to) you get quite a lot in return. I mainly use it in tandem with Google's Calendar and Reader to keep updated on concerts in my neighbourhood. Here's how:

If you don't have a Last.FM account yet, create one and start scrobbling.
After some scrobbling Last.FM should have enough data to recommend events. Go to the recommend event page, and set your location by clicking on the "change/set location" link:

It's best if you put in your location as "city, country". For example, my location is "Groningen, The Netherlands".
Still on the recommended events page, click on the RSS feed icon depicted below and add that feed to your Google Reader (or other favourite RSS reader).

You can also directly import your recommended events into your Google Calendar with the "Google" link, that's a bit too much for me. I just want to be informed about interesting events, and only add those to which I'm actually going to my calendar (we'll do that in step 5).
Google Reader should now recieve event recommondations based on your musical tastes, like this:

Clicking on the headline takes you the Last.FM page of the event. On that page, there's an attendance section at the bottom. Tell Last.FM that you're going:

The event will now appear on your event list (located at http://www.last.fm/user/myUserName/events).
The last step is to import your event list into Google Calendar, so that you won't forget to actually go. Simply click the Google button at the top your event list:

Your events should now come up in Google Calendar:

And that's it!

From now on you'll only have to do step 4, i.e. checking your RSS reader every now and then to see if there's something you like, and indicate if you're going on the Last.FM website. The events will then automatically pop up in your calendar.

Sunset Rubdown - Idiot Heart

2009-09-23T11:25:00.004+02:00

Sunset Rubdown - Idiot Heart

On September 2nd Sunset Rubdown gave a show in Vera, the local music club where I do some volunteering from time to time. Perhaps they had an off-day, because the show wasn't something to write home about. Until they played their song Idiot Heart (source), that is. "Heart-pounding new wave skitter", according to Pitchfork. Regardless of what you want to call it, it's one hell of a track.

Poster on my research

2009-09-21T15:07:00.004+02:00

Don't worry, there's nothing wrong with your eyes. The text on the poster above is indeed too small to read. The poster is supposed to be A0-sized (which is a whopping 0.84 by 1.18 meter), but on screen it's a tad smaller. There's a bigger version with readable text on my Picasa album -- just click on the image to get there.

I made this poster back in April this year for a conference, but then I tore it to shreds while trying to remove it from a wall. Double-sided tape can be a bitch sometimes. To avoid further incidents with tape I decided to order a new version on foam. After some trouble getting it to our institute (you can't fold foam, and A0 catches a lot of wind when you're on a bike) it now decorates a previous empty spot on the wall.

So, what's this poster all about, you might ask. Short answer: my research. Long answer: unfortunately the long answer is so long I'll have to spend another post or two on it. So stay tuned ...

PhD-day

2009-09-07T20:43:00.007+02:00

As a theoretical physicist working in the Netherlands, I'm a member of the DRSTP (the Dutch Research School for Theoretical Physics). I'm also a member of its students council, and as such I'm involved in the organization of the second DRSTP PhD-day.
The first one was back in April 2008 and was a lot of fun -- I'm pretty confident this year's edition will be the same. We're sticking to the same format: 6 speakers, 5 of which PhD students from the different Dutch universities and 1 former PhD student. Topics range from the gauge / gravity duality to petrophysics, and should be quite interesting (admittedly not for the non-physicist perhaps).

And can you spot the differences in the posters? I made both, and can't really decide which one I like best. It's funny how small changes can change the look quite dramatically. But perhaps I should focus less on graphical design and more on writing my PhD thesis. The bugger is due at the end of the year. Better start cracking.

Lego accessories

2009-08-31T15:44:00.012+02:00

Yup, that's my new bag. Not just any bag, mind you: a Lego space shoulder bag! Apart from the Lego space logo, there's an actual Lego figure from the 1970s behind a small display. Plus it has a Lego brick as a zipper. Does it get any better than that?

In fact, it does. The Lego shop boasts quite a number of nifty items that would look good in any household. Take for example the pepper and salt shaker set that's putting the other items in our kitchens to shame:

That's where my little collection stops for now, but in the Lego shop the list goes on. Want to impress your friends with Lego-cooled drinks? No problem! Use the Lego ice brick tray:
Of course you'll want to serve those Lego-cold drinks on matching coasters:

You know what would go good with those drinks? Lego cake!

Ok, so you don't like cake. Have some cookies instead!

And to finish it off, here's some Lego cutlery for you:
So next time you're close to one of the few Lego shops and in need of new kitchen accessories, be sure to drop on by.

Cubing away

2009-08-23T13:42:00.006+02:00

For my last birthday I got a brand new V-Cube 7. Yes, I know, it's perhaps a bit nerdy, but it's soooo cool. Where the ordinary Rubik's cube is 3x3x3, this baby is 7x7x7. And where the number of permutations of the 3x3x3 was already staggering (4.33 x 10¹⁹ to be precise), the possible states of the V-Cube 7 is an absolutely mind-blowing 1.95 x 10¹⁶⁰. That's more than the number of atoms in the visible universe! In fact, if you had one cube for every permutation and were to shrink them all down to the size of atoms, you could fill the visible universe up to 10¹⁵ times over. Now that, ladies and gentlemen, is a lot of permutations.

Apart from these dazzling numbers, it's also quite a beautifully constructed. Have a look at this amazing stop-motion video of its assembly:

And best of all, it's fun to play with. Where I can solve the ordinary Rubik's cube in just under 5 minutes, the V-Cube 7 takes me almost an hour. But today I had an incredible stroke of luck: I managed to solve it in just one minute! Fortunately, I knew beforehand this was going to happen, and I had my camera at the ready:

Okay, so perhaps I cheated a bit. But how?

Update:
As some of you already have guessed, I just played the video backward. That way it appears the cube gets solved, where instead it's just getting scrambled. And yes, I got the idea from Michel Gondry.

East coast vs. West coast in particle physics

2009-08-12T16:46:00.004+02:00

Last year saw the jaw-dropping Large Hadron Rap, explaining the LHC at CERN as best as possible to the layman in five minutes. For those of you forgot, here's the video:

This year Fermilab strikes back! It looks like science rapper funky49 made a proper gangsta-rap about the Tevatron. There's no video yet, but he's posted the lyrics on his website:

"(...) Tevatron, OG atom smasher
say hello to CERN’s party crasher, the
new “Lord of the Rings” LHC, hear me, this
be competitive collaboration baby (...)"

There has been some rivaly between CERN and Fermilab on who discovers the Higgs first. It looks like the rivalry now has entered a whole new domain ... will we see the likes of the East Coast vs. West Coast feud for particle physics?

My new turntable

2009-08-06T15:21:00.005+02:00

Have a look at this beauty:

It's my new turntable, the black matte edition of the Pro-Ject Debut III to be precise. It's actually my first proper turntable. I did have one before, but I threw it away because it's crappy construction and even crappier needle were ruining my records.

You can imagine I was pretty excited when I unboxed it at home, eager to play some records that were gathering dust. Much to my dismay I found that installing the damn thing was trickier than I first imagined. Get it out of its box, put it on a shelve, connect it, and play, right? Not so. Here is an excerpt from the user's manual:

Set-up
Make sure the surface you wish to use the turntable on is level (use a spirit level) before placing the turntable on it. Remove the two red transport screws (1) which secure the motor (22) during transportation.
Remove the transport lock (18) from the tonearm. Store it together with the two red motor transport screws (1) in the original packaging so they are available for any future transportation.
Fit the drive belt (3) around the hub (4) and the smaller diameter part of the motor pulley (2). Avoid getting sweat or grease on the belt as these will deteriorate the performance and reduce the belt's lifespan. Use absorbent kitchen paper to remove any oil or grease from the outer edge of the hub and the belt. Fit the platter (5) and felt mat over the spindle of the hub (4).

Cartridge downforce adjustment
The counterweight (6) supplied is suitable for cartridges weighing between 3,5 - 5,5g. Alternative counterweights for cartridges weighing between 6 - 9g or 1,5 - 3g are available as accessory parts. Adjust the downforce prior to installing the anti-skating weight.
Pushing carefully, turn the counterweight (6) onto the rear end of the tonearm tube (9), and so that the downforce scale (6a) shows towards the front of the player. Lower the armlift and position the cartridge in the space between arm rest and platter. Carefully rotate the counterweight (6) until the armtube balances out.
The arm should return to the balanced position if it is moved up or down. This adjustment must be done carefully. Do not forget to remove the cartridge protection cap if fitted.
Once the arm is correctly balanced return it to the rest. Hold the counterweight (6) without moving it, and gently revolve the downforce scale ring (6a) until the zero is in line with the anti-skating prong (15). Check whether the arm still balances out.
Rotate the counterweight counter clockwise (seen from the front) to adjust the downforce according to the cartridge manufacturer's recommendations. One mark on the scale represents 1 mN (= 0,1g / 0,1 Pond) of downforce.

Holy crap! That's a lot of work! In fact, it took me close to one hour getting everything right. But it was worth the effort: now I can listen to my records once more in perfect audio quality (cause the Debut III is one kick-ass turntable), and not worry about them getting ruined.

The Debt and Deficit Dragon

2009-08-06T11:35:00.002+02:00

As a non-American, I feel a bit hesitant to comment on American domestic politics. Luckily, there's Jon Stewart and his ever vigilant Daily Show:

And I thought Dutch politics is awkward these days ... guess you can always do worse.

Setting up TeXlipse and Sumatra PDF

2009-08-05T17:10:00.008+02:00

After raving about how brilliant TeXlipse is, it's perhaps time to describe my actual LaTeX setup on Windows. The key ingredients are:

LaTeX distribution: MikTeX. I currently have version 2.7 installed, which has SyncTeX support (important for forward- and inverse-searching in PDF files). I haven't tried TeX Live, but that should in principle also work (it also has SyncTex support).
Editor: Eclipse + TeXlipse.
Previewer: Sumatra PDF. Yes, that's right, no DVI files for me!

Installation is a bit difficult, but worth the while. Here's how you do it:

Download and install MikTeX 2.7 (or newer if you're up for it). Shouldn't be too difficult.
Get a good version of Eclipse. A bit more difficult, since there are gazillion versions floating on the internet. The standard ones come with support for either C++ or Java, which we don't want. The cleanest distribution I could find is the Platform Runtime Binary. Download it and extract the zip file in C:\Program Files\ or the likes. Also put a shortcut to eclipse.exe on the desktop if you're lazy like me.
Fire up Eclipse and follow the instructions on the TeXlipse website in order to install TeXlipse.
Download and install Sumatra PDF. Also easy.
And now the going gets though: it's time to configure TeXlipse. Luckily the TeXlipse folks also have a page for that. The extra ingredient from me is to add the switch "-synctex=1" to the pdflatex command, which enables PDF syncing. The pdflatex config should look something like this:
Add a new viewer configuration for SumatraPDF, and make it the top of the list so it's the default viewer. Here's how its config should look:
We're almost done. We still need to configure the inverse search for Sumatra PDF. Create a .BAT file in the Eclipse directory (or somewhere else convenient), with the following line:
java -classpath "%ECLIPSEDIR%\plugins\net.sourceforge.texlipse_1.3.0\texlipse.jar" net.sourceforge.texlipse.viewer.util.FileLocationClient -p 55000 -f %1 -l %2
There are no hard line breaks here, it's just one single line. Also add a environment variable via Control Panel -> System -> Advanced -> Environment variables -> System variables -> New. The variable name should be "ECLIPSEDIR", its value "c:\program files\eclipse" or wherever you installed Eclipse (both without the quotes).
Configure Sumatra PDF for inverse search by running the command
SumatraPDF.exe -inverse-search "\"C:\Program Files\eclipse\inverse_search.bat\" \"%f\" %l"
where you should take care to properly point to the .BAT file you created in the previous step.

And that's it. Now you should be ready to experience all the wonders of the TeXlipse + Sumatra PDF combination. Enjoy!

The perfect LaTeX editor

2009-08-04T17:15:00.002+02:00

LaTeX is great. It's math support is the best, and the automatic layout and referencing works perfect. Say if I wanted to write the Einstein field equations, all I'd have to do is type

G_{\mu\nu} + \Lambda g_{\mu\nu} = \frac{8 \pi G}{c^4} T_{\mu\nu}

in a text file (with some appropriate LaTeX specific headers), compile it, and I'd end up with

It's just brilliant.

However, most of the LaTeX editors available are just fancy text editors, with nothing quite special. Sure, they've all got the syntax highlighting and push-button compilation, but I want more. The reason I want more is because I've done some Java coding in the Netbeans IDE. Some of its features are:

Automatic code formatting. Any LaTeX enthusiast who has worked with multiple people on one file knows that your co-authors invariably mess up the formatting. Automatic formatting comes to the rescue with just one push of the button.
Live parsing. No more trying to figure out where those damn compilation errors are. Live parsing tells you with a red underline, much like the grammar check in Microsoft Word, the exact position your faulty code.
Code completion. Try it. Love it. Can't live without it. Why type the whole command when only the first few characters suffice?
Build-in documentation. Hover over a function or variable, and a nice documentation popup will appear which tells you all you need to know about that function / variable.
Subversion support. It tracks the changes you've made in the file with nice colors in the sidebar. And it automatically merges your changes with those of your collaborators. How cool is that?

The list goes on, but these are the features I miss the most in almost any LaTeX editor. Almost any, because last week I discovered TeXlipse. It's a plugin for Eclipse that adds LaTeX support. And because Eclipse is a modern IDE just like Netbeans, it also has the features above out of the box. Once I got it working (which required some effort I must admit), I couldn't be happier! Here it is action:

Notice the red cross before the line of the error, and the yellow warning sign before the line where there's an underfull hbox. Although it's not visible from the screenshot, the cursor is over the \otimes, causing the popup to appear that describes that particular command.

Although I'm working with it for a only week now, I'm pretty sure I'll stick to TeXlipse. It just makes my LaTeX workflow that much more pleasant.

Higher on the list means more citations

2009-08-04T12:05:00.000+02:00

Yesterday, when I was doing my daily routine of checking new hep-th papers on the arXiv, I came across this article: "Positional effects on citation and readership in arXiv". For anyone who will post some papers on the arXiv this is a must-read. The authors confirm that the higher your paper is on the list of daily announcements, the more likely it will get a better long-term citation record:

"We confirm and extend a surprising correlation between article position in these initial announcements, ordered by submission time, and later citation impact, due primarily to intentional "self-promotion" on the part of authors. A pure "visibility" effect was also present: the subset of articles accidentally in early positions fared measurably better in the long-term citation record than those lower down."

How do you get on the top of the announcement list? It's easy: submit a paper right after the deadline of the day before. And the deadline is 16.00 US Easter Time, which is 22.00 here in The Netherlands. To be brutally honest, I don't stay in the office until that late in the evening, but for it is a small price to pay for more citations.

It's a silly mechanism. Luckily, the authors suggest that

"(...) arXiv subject area organization and interface design should be reconsidered either to utilize or to counter such unintentional biases."

As they're both affiliated to Cornell, let's hope they have some leverage to indeed push for some much-needed interface changes at the arXiv.

First post

2009-08-04T11:41:00.002+02:00

Look here, my blog! Yes, after quite some hesitations I finally decided to create a blog. Not that I have that so many interesting stuff to say, but my personal branding coach said it would be good for my personal brand. So there.

So what can you expect? My intention is to mostly geek out about computers and physics, mixed up with a few music related post. I realize my audience might be very small, but I don't really care. Right now blogging looks like fun and I'm eager to find out if that's the case.

One last thing before I finish my first post ... curses on the person who has teake.blogspot.com! He's doing nothing with it, and I have to settle for some second-rate URL. Life's just not fair. Sigh.