Thursday, February 21, 2013

These Are a Few of My Favourite Things

Or at any rate, things that have made me happy recently, even if they aren't absolute all time top favourites.

Pausing to stand under a cascade of pink blossoms spilling over a fence on the way back from the supermarket.

Finding that an example I made to help some students has osmosed into nearly every workbook in the group.

Eating a perfectly ripe plum after a long afternoon.

Having my own keys to [parts of] the Physics department.

Lying on my bed with a supersized mug of milky tea.

Working out a proof until it suddenly blossoms into understanding of the general case.

Finding a skirt that hits at the ankle even if you're tall and high-waisted, marked down from the markdown price.

Watching and helping a student 'get' a new concept.

Scheming to make homemade hamburgers and chips on Friday night.

Drawing Koch snowflakes until the iterations get smaller than my pen strokes.

There are moments on the other end of the scale too, of course, but life is good.

Monday, February 18, 2013

Things they said

Discussing Lent at Sunday School, we mentioned doing things like giving up chocolate or taking up reading your bible. So one little girl asked "Can I eat chocolate every day for Lent?" Uh, not quite.

Also at Sunday School, one seven-year-old didn't like the way a game was being played. So she marched over to her own game and announced "I'm going to play this in the third person."

In my other natural habitat, the physics department, from a grad student who's competent in such mathematical topics as multivariate calculus and tensor analysis: "Why do minus signs have to be so confusing?"

And on the blackboard after a lecture involving the emission of UV light: "the ultra-violent catastrophe". Guess Max Planck was more of a hero than I thought!

Savo 'lass a lalaith.

Saturday, February 16, 2013

Research

Today while I was talking to Sir Laughs-a-lot, because this is apparently what grad students do, we formulated an algorithm for research. I, uh, decided the world would be a better place for my putting on the internet. So here goes.

1. Get confused. (We totally have this one nailed. But as Sir L says, it can be fun.)

2. Get unconfused. (Easy, right?)

3. Write a paper. "Look! I'm unconfused, look at me! You can be unconfused too."

4. Win Nobel prize; become rich and famous (optional).

We were doing step two for a thermodynamics problem which has technically already been solved, but only by other people and we ended up with a (hypothetical) balloon that filled the whole universe. This is why I'm studying physics.

Friday, February 15, 2013

Friday Five

1. Lectures started this week! It's a bit odd only having nine hours of class time in a week, but there still seems to be plenty to do. I wonder how many of us are realistically putting in the other 3+ hours a week on project work.

2. Most of my project time this week has gone to watching video lectures on machine learning (via Coursera). One of the neatest techniques is an algorithm called gradient descent. For each iteration it considers each parameter A and a function J to minimise. Then it sets A to be A - c(dJ/dA) for a learning rate constant c. This means that at the top of a hollow, you move down the steep sides rapidly. As things shallow out towards the minimum, the steps get increasingly smaller. Awesome. (If you think of a derivative as the slope at a point, you can see this, as well as why the algorithm always moves towards the lowest point.)

3. Next week is going to be a toss up between machine learning videos and reading papers on things like Kalman filtering. Both are interesting and a little zombie-ish in that they tend to steal my brains.

4. I think students might be anti-zombies, since Statistical Physics, Quantum Mechanics and Partial Differential equations somehow have similar effects. Considering how many things are like that, it must be me, right? They can't all be zombie subjects.

5. Despite a bit of grumbling, this is totally what I signed up for and it's really great. Now I just need to get my brain into gear so I can stop confusing scalar products with scalar multiplication, which, despite the names, are not the same thing at all. Oops! I blame the zombies.

Friday, February 8, 2013

Book Log: The Lord of the Rings Part 1

We all know that Tolkien's The Lord of the Rings is one novel and not a trilogy, right? It was only published in three volumes because of paper costs and such. So I can just write about the three parts as I read them without ranting about how the first two parts do not have proper endings because they're actually middles and it's a pity so many recentish novels seem to think they can end as incompletely? Awesome.

I've read The Lord of the Rings too many times to want to write a proper reviewy thing as I read it. I get a bit too excited about details like when exactly the reforging of Narsil is first mentioned and will forget to say anything about the obvious and crucial aspects. So I thought instead I'd sort of pick out the theme of fellowship from The Fellowship of the Ring and talk a little bit about loyalties and motivations. (I shan't try to avoid spoilery things, since if you haven't read the book you've probably seen the movie.)

The most obvious at the end of the first part is perhaps Borimir's loyalty to Minas Tirith. I don't think it's just loyalty that makes him so desire the ring, but certainly the loyalty nearly gave the ring a path to being used as it wished. It's interesting to contrast Boromir with Aragorn, who shares a strong loyalty to the city, but tempers it with the counsel of the Wise, a better sense of scale and somethin akin to greater maturity (not that Boromir's immature by any ordinary standard). It's also interesting to compare Sam to Boromir, since he's loyal to Frodo in a way that strikes me as similar to Boromir's loyalty to Gondor. Sam's big tests of character are much further on, though, so there may be more to say later.

Legolas and Gimli are fiercely loyal to the elves and the dwarves respectively; but in Lothlorien and Moria both have to face up to certain shortcomings of their own races and merits of the other's. Ultimately their loyalties don't seem to lessen so much as to mellow into something wherein they can appreciate other civilisations along with their own. They grow, perhaps. I'll try to remember to revisit this thought at Helm's Deep.

Merry and Pippin follow Frodo, although Gondor and Rohan will, I think, claim their loyalty later. Gandalf is rather mysterious; I am inclined to think that he answers to Illuvatar. Gandalf the White may shed some light on that when I get there.

Frodo goes through an interesting change that pretty much frames the first part of the novel. Early on Bilbo says that Frodo still loves the Shiore too much to leave it. Although Frodo thinks of following Bilbo, he never does. It is eventually the threat to the Shire, through the ring, that motivates Frodo. But by the time Frodo sits upon Amon Hen, he is wrestling with fear and his knowledge of what he must do. The Shire isn't particularly a player in his decisions any longer. His new loyalties are perhaps to Middle Earth a a whole; I'm tempted to say to what's right, but I think there are right and wrong ways to express loyalty, which may be the difference between Boromir and Sam.

Frodo is beginning to gain some of the perspective that tempers Aragorn's actions and which Boromir never found. But "the finest hobbit in the Shire" is made of sturdier stuff than Boromir from the start, I think. Even Gandalf and Galadriel are sorely tempted by the offer of the ring; Boromir would take it by force; Bilbo only gives it up with much assistance from Gandalf. Frodo, even after bearing the ring and after the Morgul wound freely offers to give it away. And that, I suppose, is why he must be the ringbearer.