Survey

I occasionally get surveys to do from Yougov, for which they either give me a small amount of credit (which I can claim as real money once it reaches a certain amount) or an entry into a prize draw. Today’s was a prize draw survey, on the topic of cars. And so mine went:

– Have you read the Sunday Times in the past 4 weeks? (Yes)
– Do you own a car? (No)
Congratulations! You have completed the survey

Parallel worlds

I’ve been messing around on Yahoo! Answers recently. Someone asked the question “Why do some physicists think parallel worlds might exist?” I spent far too long on my answer (especially since the fun parts of quantum physics won’t be on my upcoming exams!) but am fairly pleased with it, and it took me back a bit to when I was studying such things. Answer reposted below:

That’s what is known as the “many-worlds interpretation” and is one of the ways scientists try and think about the baffling world of quantum mechanics.

The classic experiment and the best way to explain is the double-slit experiment. Imagine you have a plate with two narrow slits cut in it. You have a light on one side, and a screen on the other. When the light shines through one of the slits, it produces a diffraction (spreading) pattern. When it shines through both slits, there are two diffraction patterns which interfere with each other, producing a different interference pattern. This is typical for waves, and you can show a similar effect with ripples on water.

Now it is also known that light occurs in indivisible “packets” called photons. If you decrease the intensity of your light source you can get it to emit only one photon at a time. But you still get the interference pattern on the screen! Why is this weird? Because if you only sent one photon at once, what is it interfering with? The quantum answer is that it interferes with *itself*!

Somehow the single photon must have passed through *both* slits. There are a few ways to think about this. One basically says that it is impossible to know which slit the photon went through, and therefore it went through both. Unfortunately this basically means that the photon no longer has a position you can pin down, which is a bit weird. This is just like Schrödinger’s cat being in a box where you can’t tell if it’s alive or dead, so you say it is both at once. [1]

So as an alternative to that weirdness, some scientists [2] thought up an explanation just as weird, if not more so – the many-worlds interpretation. In this version, the photon remains localised (i.e. it has a defined position). But the universe splits! In one universe the photon goes through the left slit, and in another it goes through the right one. We only see what happens in one universe, so we think photons stay localised. And then somehow on the other side, the two universes interfere with each other to give the pattern. This is like saying Schrödinger’s cat is alive in one universe, and dead in another.

Hope this helps, and apologies for the length, it’s pretty complicated to explain and I got a bit carried away! There’s more info about the many-worlds interpretation here: http://www.hedweb.com/manworld.htm

“…those who are not shocked when they first come across quantum theory cannot possibly have understood it.” – Niels Bohr

Notes:
[1] Schrödinger didn’t actually believe in his cat, it was just an example to show how weird quantum mechanics is
[2] Fun fact, the guy who proposed this first was the father of Mark Everett from the band Eels.

Wikipedia Day

I’ve been following the Wiki dramahz going on today (and just spent a fruitless 20 mins trying to explain it to one of my housemates), but managed to completely miss that it’s Wikipedia’s 8th birthday! See the official blog. I can hardly believe it’s 8 years old, and even less that I’ve been there for almost half that time. Happy Wikipedia Day everyone!

Upgraded

It’s funny, I’m normally very keen on keeping all my software up to date, but WordPress is just enough hassle for me to make an exception. I was trundling along on 2.5 for ages now, and given that it keeps nagging me to update to not 2.6, but 2.7, I thought I should get on with it. Did this from the family computer running Vista, and tried using Windows Explorer’s built in ftp, which as I should have guessed was a mistake – soooo slooooow! When it seemed to crash I gave up and used WebFTP. Anyway it all worked out in the end. They appear to have entirely changed the interface again, how nice. And look, the post writing box has a word count! *glee*

Another reason for upgrading is that I’ve been feeling creative recently and want to make a new theme for my site. And not just pinching one from http://www.freewpthemes.net/ like I did last time – although it is CC licensed, and there are some very nice ones there. I mean hacking one together from HTML and CSS, so I didn’t want to do that and then find out 2.7 messes it up. Having a computer that can run Dreamweaver and Photoshop slightly faster than an asthmatic snail will help too. I do like my current one, but having used it for a while it’s a little too bright for my tastes. Plus I want to play around with CSS again, like the big geek that I am. Hopefully I’ll get it done sometime before heading back to uni.

In Wikipedia news, I blitzed a lot of the backlog for the UK Portal. Then I found that the Signpost (where I get my FA updates from) hasn’t been published since 1st December :-( I really ought to help out with that, so there’s another distraction. I want to put the UK Portal up for featured status soon too, will probably not go for the massive tabbed redesign I was planning. Also next term I really ought to grab some material from the college library and work on the Downing article, it is a little embarassing to have been on Wikipedia so long and never actually written much of substance. The Materials dept could possibly use an article too.

Write Or Die

So, I was needing a kick up the backside to get some work done. And as is usual when trying to knuckle down, I found myself browsing Wikipedia again. This time I ended up at the National Novel Writing Month (NaNoWriMo for those in the know) page. This is something I’d heard about before (after all, I did try – and fail miserably – at NaBloPoMo) and always been pretty interested in. So I clicked through to their homepage. Turns out it was last month (November, i.e. the same as NaBloPoMo). Anyway three little words on their homepage caught my eye – “Write Or Die”. Liking the threatening tone (and I only realised later, probably drawing a subconscious parallel to the anime “Read or Die”, one of my absolute favourites), I clicked the link. It turns out some guy, aptly named Dr Wicked, has written a nifty little web app which doesn’t so much encourage you to write, as FORCE you to. You’re presented with a blank text box, but instead of being able to stare at it in horror while your mind is empty, you have to write. Otherwise the screen border will start to flash, and sooner or later it begins to play annoying sounds. And you have to KEEP writing, until you reach a word count or time limit that you set before hand. A particularly devious mode replaces the annoying sounds with something else – if you don’t keep writing new words, the old ones you did manage begin to disappear before your eyes. Genius.

So anyway, that’s how I managed to write this. It makes such a change from my usual, glacial writing pace, with popping back every few seconds to edit and re-edit, then realising I have to reword everything else to make sense. I need to use this more often. Now if only I could start going to bed at sensible times…

http://lab.drwicked.com/writeordie.html

P.S. I’m on twitter now – http://twitter.com/thewub

Oh dear god, it’s only now I’m previewing this post in wordpress that I realise how long it is compared to my usual. Yay, I guess!