QFT is (not) hard

Yesterday was our faculty's postgrad symposium, where science students of all descriptions attempted (usually with some measure of success) to explain to science students of all other descriptions what their research is all about. This necessitates some creativity and has left me thinking (not for the first time) about whether or not QFT is indeed inexplicable. It seems worth writing up a few thoughts here.

QFT is hard.

There's a reason that nobody less than four years out of high school gets QFT (for an approximate value of nobody and allowing 'gets' to be ill-defined) and nobody with less than six years of tertiary education has actually used it in any practical way. (Again, generalisation, but I don't think it's far off the mark.) QFT is a very abstract, mathematical theory and divorcing it from the mathematics is like trying to explain swimming without water. If you want to understand QFT, come back when you have a degree's worth of mathematics. This is perhaps a little too depressing, so let's try another tack. 

QFT is not hard

Sure, the scientists who do QFT research need lots of training and deal with scary equations all day, every day, but that's not the heart of what they're doing. They're actually doing calculations on "god particles" and quarks, which are basically very small marbles glued to elastic bands which are other particles called gluons and the gluon is massless which means it's like a fish that can swim through the god particle molasses slickly, unlike the other particles, which are like whales because they have masses.

Now, I will admit that our building houses not just the physics department, but also the oceanography department and the Marine Research Institute, but we are separate departments. A quark or a Z boson is nothing at all like a whale. In fact, the work I do on a day-to-day basis involves talking about mathematical abstractions that can be experimentally tested using the ideas of such particles, but doesn't really talk about particles at all. So while I do think that non-specialists should be able to get an idea of what's going on in QFT, I'm not convinced that these analogies do much more than make people think they know what's going on. Which is perhaps worth something, but seems suboptimal.

QFT is (not) hard

QFT is an abstract theory based on abstract mathematics. If you want a genuine feeling for how it behaves, you need a genuine feeling for how maths behaves. To reuse an analogy (since I've decided they're not all bad), you can't understand swimming if you don't know what water is. QFT is related to abstract maths just as intimately and shying away from it doesn't help. But what I think we miss is that all you need is a "genuine feeling for how maths behaves". I say 'all', but of course such a feeling can be hard to come by. However, it's an awful lot easier to come by than a degree in mathematics. It almost has to be.

I don't think you need to be able to calculate a commutator to get a feel for what's going on in QFT. I do think you need to know that sometimes in maths, as in life, order matters. 2 + 3 = 3 + 2. I don't care whether you put on your hat and then scarf or you scarf and then hat. But pq is not the same as qp and you should put on your socks before you put on your shoes, unless perhaps you're going to a fancy dress party.*

For some reason we don't seem to want to explain QFT this way. Perhaps it's because we've all learned in school that maths is terrifying. Perhaps it feels like it takes us too far off topic. (I feel this every time I try to give a talk about QFT, but I find there's nothing to say if I take out the maths.) Perhaps we just haven't thought about it enough. (We almost certainly don't think about science communication enough.) Perhaps it is happening, but I'm not aware of it (and neither are my scientist friends, which would mean it needs way more publicity).

I'm still working out where  this leaves me. It means that when I talk about QFT for a general audience, I don't shy away from the maths. Maybe it means I need to write and/or talk about these ideas more often (she said, guiltily writing her first blog post in months). Maybe it's enough to be aware of it and to talk about. Maybe I need to pick fights about it. Maybe (definitely) it's not all a problem for me to solve, all on my own, today. But it's a topic that deserves some thought, in the midst of marking and debugging and trying to put in those six years you need to learn to use QFT. We'll see.

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* I feel like a cheat putting in mathematics without explaining the physical significance. The p and q here are representing the tools we use to measure the position and momentum (which gives us the speed) of a particle respectively. The maths tells us that the order in which me measure them matters, because pq ≠ qp. This means that making one measurement must somehow corrupt the other (it doesn't tell us how that happens, sadly). This in turn means that if we measure the position correctly, we can't measure the momentum and vice versa. This is Heisenberg's Uncertainty Principle (which is one of the most obvious and well known consequences of order mattering, although not the only one). You can talk about thought experiments, like the Heisenberg microscope, to make it seem more intuitive, but it comes from the fact that if we choose maths that gives us the right answers, order matters when you write down p and q.

Definitions and Discoveries

At first glance it seems that it would be rather silly to mix up the ideas of a definition and a discovery, but at least in maths (and perhaps especially theoretical physics) it's surprisingly easy to do. Both processes produce rules that allow us to go on and derive new rules and descriptions -- the big difference is where they come from.

Might require a change of maths.

Suppose, for instance, that I want to construct a rule using the word "good". Then I would work out what the word "good" means for the rule by seeing how it works in the world -- I would discover it, rather than defining it. (There might be situations where you would choose to define it differently from how it works in the rest of the world, but you would have to be clear that you were doing something funny then.) This is rather like how we decide to write the description of gravity as pulling things together. Mathematically you could write about it as a force that pushes things apart, but that wouldn't describe the gravity we experience. Likewise, if you want to describe arithmetic as we know it, you can't decide whether 2+3 and 3+2 are the same thing. You discover that you don't get the expected results unless they are. (One might decide to define it differently anyway, but then one would no longer be talking about ordinary arithmetic.)

Things get more complicated if I have a procedure that involves putting "un" at the beginning of words. I can't go out and discover the meaning of "ungood", because it's not a word you can find in the world. Nothing about the way people talk changes if I interpret "ungood" as meaning "butterfly" or "convenient" or "pirouetting", because people don't say "ungood" in the first place. Situations like this tend to crop up in the intermediate mathematical steps of a physics problem. I've translated the situation into equations and now I want to solve them. Solving equations doesn't mean anything physically, although the solutions should be something we can translate back. That means there aren't clear physical requirements on what is or isn't allowed in trying to solve the equation. 

If I want to be able to use the "un" procedure, I have to come up with a meaning for "ungood". There's nothing stopping me from picking any definition I like -- but some will be more useful than others. I'd like to pick a definition that means the "un" procedure does the same thing it does to other rules. "Decided" becomes "undecided", "expected" becomes "unexpected" and "forgettable" becomes "unforgettable", all of which do mean things already. It makes sense that when "good" becomes "ungood", it means the opposite of "good". We might define "ungood" to mean "bad".

We don't have to define it that way, though. We could go by similar phonetics instead and define "ungood" to mean "unguent". The "un" rule wouldn't work as expected any more, of course. But if I were writing a speech-to-text program, say, that might be less important than the phonetics. Besides, it's not like the "un" rule is infallible anyway -- look at how "til" becomes "until". It's only if I want the definition to work in a system where the "un" rule always produces opposites that defining "ungood" to mean "unguent" would be inconsistent.

The same thing happens mathematically. If something doesn't exactly match up to some physical observable, we need to define what it means. Some definitions make more sense than others when it comes to translating back and those are the ones we choose. But unlike making a discovery, it is a choice. We decide that we want certain rules and procedures to do what they do elsewhere and choose to define things accordingly. The definition isn't forced upon us by the way the world works. 

Why do I care about such a subtle difference? If you just want to apply the rules, it doesn't really matter. But if you want to understand where they come from and what makes physics tick, you need to know what's required to describe the world and what's just a helpful way of thinking about intermediate maths. And that's why I'm quite sure I'm neither the first nor the last physics student to say "Oh is that just a definition? It all makes sense now..."

Savo 'lass a lalaith.

Theme Thursday: Sport?

Boogie at the UCT Ballroom and Latin Dancing Society

Cari at Clan Donaldson runs the Theme Thursday linkup, and since she says there are no rules, I will persist in joining in erratically, even when I'm not really in the target audience. Also I will post-process the heck out of mediocre pictures until I can convince myself that they're arty. And claim that the social dancing when Ballroom lessons are cancelled for the holiday is a sport. (Actually, looking at what other people have linked, this last might be on-trend.)

Straight off the camera cellphone

 If I go to black and white, I can convert the motion blur to graininess (yay, unsharp mask) and call it a feature, yes? It was fun to play with, at any rate; and a fun evening to remember. So perhaps I can file this under "further perks of [still] being a student". It fits somewhere below "Science is cooool" and above "No, actually, I don't get to take the university holiday off. I need to learn everything about everything before my funding runs out."

 
Savo 'lass a lalaith.

Of spin and other nonsense

From the Oxford English Dictionary:

spin:

noun 1 A rapid turning or whirling motion

 ...

1.4 Physics The intrinsic angular momentum of a subatomic particle.

...

noun 3 [in singular] The presentation of information in a particular way; a slant, especially a favourable one

I was going to write something about covering groups, which I've been reading about today, but one of the applications of covering groups in theoretical physics is in linking quantum spin to rotations. Spin is fascinating and weird. I got sidetracked.

I suspect that spin is not really all that weird, if one thinks about it properly. But in the process of discovering what exactly holds the world together, one doesn't always come across ideas in contexts that make it easy to think about them properly. Such is the case with (quantum) spin, which, despite the name, does not involve any rapid twirling or whirling motions. In fact, all the talk about twirling and whirling could probably be classified as spin in the third sense "presentation of information in a particular way; a slant, especially a favourable one" (but not necessarily an accurate one).

Spin is just a property of a particle (I'll disagree with the OED on its technically needing to be a subatomic particle, but admittedly that's overwhelmingly the context where we talk about spin.) It's easy enough to imagine a particle having a position. It can have a mass, which we tend to think about in terms of how much it weighs -- although the ideas aren't quite the same. We're happy to think about a particle having a speed. Other things are harder to imagine.

We know that there's a thing called electric charge. It's what makes lightbulbs shine and computers compute. It's the reason you can rub a plastic ruler on your head and use it to pick up scraps of paper; and the cause of thunder and lightning. It certainly seems to exist. But what exactly is it? Well, it's electric charge. If we describe it as being like something easier to imagine then we're describing it as being something different from itself.
 
There's another thing called spin. People sometimes try to describe it as whirling and twirling, because that's easy to imagine and the context in which it was first noticed. In fact, it can be linked very closely -- but not identically -- to the idea of rotations using the mathematics of covering groups. However, spin is not about twirling and whirling, so we end up describing it as something other than itself when we take that route. It tends not to end well.

There are two yellow lines in the sodium spectrum, not just one.

Spin is a thing that means splitting the light from a sodium lamp with a prism produces two yellow lines, instead of just one. There's a yellow line for each kind of spin. Spin is the thing that means if you fire a stream of particles into a magnetic field, some will go up and some will go down. It means electron energies are arranged twice as efficiently as you might expect. Like electric charge, spin has noticeable effects. Even if we can't exactly imagine it, it makes sense to talk about it.

That's where the maths comes in handy, of course -- it gives us a way to talk about things like spin, even when we don't have a convenient way to imagine what they 'actually' are.

Savo 'lass a lalaith.

I should be debugging

, but the server's down and sometimes it's good to step off the hamster wheel. I think. Maybe. It's okay to step off the hamster wheel, right? Are we allowed to admit that there is a hamster wheel?

I'm not complaining, mind you. I love my work. Really, laugh-out-loud, love theoretical physics and seeing how ridiculously, beautifully abstract mathematics can describe the real world and how things actually happen. I love C++ debugging somewhat less, but I can accept that it's part of the package. Which isn't to say it's not a bit of a hamster wheel.

On Saturday at a workshop on science communication I told an auditoriumful of people that I was infatuated with Grassman algebras. That isn't a hamster wheel. It's something to remember and savour. It's a reason to get on the hamster wheel when the wheel needs to be turned, even if I don't seem to be going anywhere.

Grassman algebras are very neat. See, ordinary numbers commute. That means you get equations like

ab - ba = 0

which is to say

ab = ba.

Five times three is the same as three times five, and for most of the things we want to use maths for, that's awfully convenient. If I switch the length and breadth of a room, I don't want the area to change! But sometimes switching things around does change things. Putting on my shoes and then my socks is not the same as putting on my socks and then my shoes.

It turns out that in particle physics there's a family of particles -- called fermions -- that behave like this. If fermion the first and fermion the second are identical (for instance, they might both be electrons), it still matters which order I put them in. No, that's not intuitive, but it does seem to be the way nature works. If I switch fermion one and fermion two, so that instead I'm looking at fermion two and fermion one, the mathematics I'm using needs to have a minus sign attached. And that's where Grassman numbers (the things you use in Grassman algebras) come in. Grassman numbers don't commute, they anticommute:

ab + ba = 0 

which is to say

ab = -ba.

In fact, Grassman numbers behave just the way fermions seem to. That means that while I might describe the length and breadth of a room using ordinary ("real") numbers, it's more convenient to describe fermions using Grassman numbers. I have to modify the rules of maths slightly to make sure that they anticommute, but otherwise I can carry on just as before. The kind of number I'm using does most of the work and I don't have to keep accounting for the odd behaviour of fermions. The fact that they do strange things when you swap them around is built in.

 I think that's pretty. Just about pretty enough that I might muster the willpower to go and ask C++ why it insists that the solution to my equation is infinity. (The solution is not infinity. Unless I've given it the wrong equation. Or the wrong method for solving the equation. Or I accidentally typed +∞ before printing the answer. Maybe I'll go check that last one.)
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Savo 'lass a lalaith.

Patterns

 Some correlations without much thought on the mechanisms behind them. Things I've noticed. 


Three participants at the Cape Town heats of the FameLab science communication competition prepared their talks for both regional rounds before the day. (The others prepared the second talk during lunch break.)
//
The same three participants were the three sent through to the national stages.

(Did they [we] do better because they [we] were more prepared, is there something that affects both or is it just chance?)


Researchers are evaluated not by what they understand (which is hardly measurable), but by "research output" or publications.
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Students are told that it's more important to understand the topic than to worry about the grades.

(This is partly to do with what we can measure and partly to do with how we look at things and definitely a question that goes much deeper than what I've written here.)





If I get to  bed early, I'm much more capable of being productive in my work the next day.
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A lot of fun-sounding events are run in the late evening.
//
There's a stereotype about scientists not having social lives.

(Even the most obvious way of linking these doesn't involve social awkwardness. One might argue that it implies it, I suppose.)


Mathematica is probably* the most expensive and widely-used symbolic programming language out there.
//
It also has the best pattern matching capabilities.*

(My supervisor likes to point out that, even so, it's a terrible stand-in for your brain.)



*I've heard so and it sounds plausible, but I haven't looked it up for myself.

What exactly counts as open?

I'm currently writing a paper for a journal that accepts submissions only in .doc format. That doesn't sound like a problem – everyone uses Microsoft office anyway, right? Well, no, I don't. Because MS Office doesn't run under Linux, which I'm using. And even if it did, there are places I'd prefer to throw my resources, given a choice. But aren't there open source alternatives that can produce those files? Well – kind of. LibreOffice will produce a .doc file alright. And if it contains straightforwardly formatted text with the occasional picture, MS Word would handle that file fine. However. I need equations. And while both LibreOffice and MS Word have equation editor functions, they're not entirely compatible. Nor are they particularly fun to use. Why can't I just use LaTeX?

Well, okay, I know why I can't. It's a general science journal, and unless you're doing fairly mathematical science, the LaTeX learning curve may not seem or be worth the (relative) ease of use. (And, I suppose, not allowing LaTeX forces me to consider if I really need to include that obscure equation in the paper.) LaTeX documents are not, for most people, as easy to read and edit as is a .doc file. It is free, though. Which MS Word is not.

It raises an interesting question about which method is really more "open". Requiring Microsoft formats means I need to buy – or, more realistically, borrow – an expensive piece of software to contribute to the journal. Requiring LaTeX formats forces contributors to pick up a non-trivial skill set before submitting. Neither of these is really entirely open. Perhaps simply offering a choice of format would be a reasonable workaround, although it does still feel like a workaround. Improving the compatibility of LibreOffice (or other open source office suites) with MS Office, while far beyond the reach of the journal, might be a slightly better fix. I think that will happen, but not until long after I've written this paper!

In the meantime, I'll be sulking in the corner because a side effect of using an office suite format is that I can't work in vi.

Friday Five

1. It's Sir-Laughs-a-Lots' birthday tomorrow. (Happy birthday!) We're going to do silly celebratory student things. No, not that kind. The kind where you realise you have the reading comprehension of a grad student and a pile of children's books and what are you waiting for? Yay.

2. Today I wrote my last test of semester, and our lectures are finished. Exams are looming only in a manageable couple of weeks, so tomorrow we're going to do silly celebratory student things . . .

3. The test I wrote today may be the last maths test I ever write. (I take all my courses from the physics department next semester, and if I'm lucky that could be the end of coursework.) It's kinda weird.

4. Do I sound like Hermione Granger if I say I want an analysis textbook for bedtime reading? We've touched on functional analysis in this PDE course and while I don't feel much need to do the proofs myself (though it would be fuuuuuun), but I think it's be interesting, useful and, relevantly, doable to get a sense of the terminology and what the results actually are. Maybe I could find an analysis for physicists book. Hmm.

5. Although while I don't want a full-of-detailed-proofs book, I kind of want a rigourous one. We can pretend that makes sense, right? It's like, I was talking to one of my lecturers about an applied physics course and he said "Well, for a pure mathematician like yourself [. . .]" Now, I'm certainly not much of a pure mathematician if I haven't even read much analysis (I do know a very little), but I guess I'm pickier than most about maths being done properly. As it should be.

And there's today's allocation of nerdery. If you know of a readable introductory source on analysis, I'd love to know, though I don't promise I'll actually get to reading it.

Savo 'lass a lalaith.

Book Logs: Children's Fantasy

I finished two children's fantasy classic-y things recently, and thought I'd write about them together, although it probably won't turn out to be dreadfully matchy.

The Magician's Nephew by C. S. Lewis

Sir Laughs-a-lot and I have been working our way through the Narnia books together, although the order has got a little muddled (we did at least start with The Lion, the Witch and the Wardrobe). His childhood, unlike mine, was not filled with rereading the Narnia books over and over and over (they're short - I could get through a couple in an afternoon) which meant we came at it from quite different perspectives. He wanted to know what would happen next and was surprised by the surprising bits. I was bundled up in a sort of anticipation that's almost worse than suspense. Which is not to say that I didn't enjoy it - but I think reading aloud and reading together made it more obvious how much my mind was other places in the story than what we were actually reading. It takes a bit more effort to relax into the moment than otherwise, perhaps. Having said that, if I haven't read a book, I spend a fair bit of brainpower on second guessing what'll happen next, so maybe that's just me.

I think I have read the book too many times to write a brief impression post without being either dreadfully specific or taking more time away from my mathematics than is quite wise. I think it may be my favourite of the Narnia books, though we'll see as we read further!

Redwall by Brian Jacques

This is also a book that I first read as a kid, but I can't say I'm nearly as nostalgic about it. I read it because I needed a light read and it was on my Kindle app from months ago when Amazon had been offering it free. I enjoyed reading it and was drawn into the story, but I remain a little bemused as to why people get so very emotional over the series.

The setting - an abbey of mice sheltering various woodlan creatures, attacked by a horde of evil rats - is admittedly quite awesome. In "On Fairy Tales" (I think!) Tolkien draws a distinction between fantasies involving talking animals and "beast tales", which are essentially stories about everyday life, acted out by animals. (He points out that this allows for rather harsher points against some animals than wemight be comfortable with against actual people.) Redwall certainly has elements of that. But it has ancient prophecies and legendary sword and visions in dreams too, which seem to make it fantasy anyway. The combination works well. I will freely admit to spending chunks of time reading Redwall cookbooks and otherwise revelling in the setting.

I think what bothers me about the book is what I'm tempted to call Heaviside character development. In maths, a Heaviside function is zero up to a certain point, and one everywhere after that. It's not continuous. A lot of character development in Redwall feels to me - I think, maybe - like a series of Heaviside functions. Matthias is a bumbling Redwall novice. Oh no, Cluny the Scourge is coming! Level him up to inexperienced warrior, quick! It's not implausible that the change would happen - the change is a big part of a good story, for me - but I'd have liked to see a bit more of the internal turmoil and growth and not just a Heaviside archetype function. The plot felt a little like that too - different elements didn't always seem like consequences of what had gone before. They just kinda happened.

That said, I definitely enjoyed reading the book. I would certainly be less nitpicky if I didn't know other people adored the series. I liked the book (and the rest of the series), but I think it gets a bit too Heaviside-ish (and perhaps formulaic) for my liking.

End of Semester

I sat down to study today. I cleared my desk properly for once, and finally actually handwashed the tie-dye shirt that's been sitting there (now it can go into the laundry with everything else). I gave my hopefully-not-dead-yet pot plants some attention that they probably needed quite a while ago, and got mud all over my notes and the carpet. So while I was cleaning that up I gave the rest of my room a quick going over too.

It's almost procrastination, but the tidy, organised environment did seem more conducive to sitting down for two hours and making maths notes. Besides, it all needed to be done, right? It's nice to revel in the straight lines and neat corners that come with exam season before it really gets going.

Once exams are actually upon me I know those corners will seem poky, but a (relatively) clear schedule and a clear desk look quite inviting right now. There's space to breathe.

Not-Friday Five

1. We cooked spaghetti and meatballs for supper Friday night and it turned into a fancier meal than I expected. I'm not sure if it was because making meatballs is a little more effort than I usually go to or just Friday night fanciness or some happy serendipity, but it reminded me that cooking can actually be fun. I need to find more time and energy for that on a regular basis.

2. Quantum physics is weird. Niels Bohr (one of the founders of the subject) once (somewhat) famously said that "Anyone who is not confused by quantum mechanics has not understood it." This makes for some really cool stuff, but also makes it tricky to tell whether there's a typo in your notes or things really are just that weird.

3. I spent quite a while persuding the campus bookstore to source books from the suppliers for me. The online people would do it happily, but they couldn't process the gift card I'm using to finance the purchases. However, I now have a couple of books I've been wanting to read - that weren't even on special - on the way. This is exciting!

4. My siblings have all attended schools that presented book vouchers with academic awards, but I never did. I feel like part of the club now that university's doing it too.

5. Wednesday was a public holiday. It was wonderful to have a day off from classes, and while chunks of it were filled with homework, other chunks were filled with a tie-dye project It was fun! I could get addicted to this stuff.

Work and Play

I downloaded photographs for the first time in ages, and these seemed to more-or-less cover the spectrum of stuff I've been doing.

First year labs - taken during a lull in the questions. Using a torsion balance to determine relative densities. Demonstrating is actually a pretty cool job; and it makes for more interesting pictures than most of my "real" work (the stuff I'll hopefully get a degree for). You can just picture me moving between the computer and my notebook for that.

Afternoon tea - just off from the middle-of-town traffic is a lovely Victorian garden with hedges and archways and benches and grottos, which I was too busy exploring to photograph - maybe another time! After that it was time for tea. We try to do something exciting most weekends, although that sometimes means making tea and drinking it without doing work at the same time. Those times are slightly less photogenic, but they're good too!

Book Log: Goodnight Mister Tom by Michelle Magorian

("Good night" seems like two words to me, but it's one on the cover. Oh well.)

One of my criticisms against 'Skull in Shadows Lane' was that it read like a children's book (which it was, so it's not a terrible thing). Goodnight Mister Tom, which is also about children in wartime England, did not read like a children's book. I think this is a good thing (certainly, I enjoyed it), although part of me wonders if it really is a children's book.

William is evacuated from his meagre home in London to a surprisingly pleasant place in the country, where he stays with a crusty, but kind childless old widower: Mister Tom. Will blossoms in the wholesome new environment and it's a delight to watch his character unfold. Part of the delight, certainly, is being able to see things coming when he can't. I'm not sure how much that would change between an adult and a child's perspective.

It's a little odd to realise that I just don't know. As I write now, looking for an example that's more adult-oriented than kid-oriented, I can't think of a specific example. It's rich - I found some of the Heidi parallels rather fun, especially when somebody mentions the novel in a different context, but I don't imagine every reader would notice/appreciate that. The division probably doesn't have much to do with age, though. Some of the topics it deals with are horrible, but it does handle them well. I guess I wouldn't read it to small children, but that doesn't mean it's not a children's book at all.

I think I'll take it as this novel correcting the fault I found with 'Skull in Shadows Lane'. It has as much depth and colour as I could ask for, without particularly moving out of the realm of children. There's lots going on, but it's understandable. And if it takes more than one read to get all the goodness out of it - well, that's a sign of a good book, isn't it?

'Goodnight Mister Tom' is a coming-of-age novel that looks at some relevant topics of varying difficulty (abuse; discrimination; "gifted" education; interactions of family and state) rather well. The author loses herself very well, so that I'm not thinking about gender equality in education, but only wondering whether or not Connie will be able to go to high school. Which may lead me to the same topic, but lets me think about it in my own way. And I think these topics deserve some thought.

I enjoyed this. I'd like to read it again at some point.

Book Logs

I've finished a handful of books in the last couple of weeks (mostly the last week, which was a holiday from lectures, if not university work) and since it seemed unlikely I'd write posts for all of them, I'm going to put a snippet about each here.

The Lord of the Rings
J.R.R. Tolkien

I am always impressed by the immensity and grandness of this story by the time I finish it. It starts out merely cheerful and exciting - by the end it makes me wonder if I could ever do anything so worthwhile. Then I remember Frodo telling Gandalf that he wished he needn't have lived in such a time, and Gandalf's response about having to live through the time we are born into (although I've a feeling he phrases it more eloquently). I can thus convince myself that I don't need to be a Frodo or a Samwise or an Aragorn or an Eowyn.

It's harder to justify why I shouldn't strive to create as magnificently as Tolkien did. Exactly what that means is a little fuzzy, but I come away feeling inspired; like it's no good if all the book does is make me sad and happy and incredulous and awestruck. One needs to do something, whether it's a trip to Mount Doom, making sure Gaffer Gamgee has enough to eat, creating something to reflect the glory of our world, devouring knowledge like it's gong out of fashion or - just something. It doesn't seem enough to let life happen to one, after that account. One must do something.

OpenIntro Statistics
openintro.org

It's been a while since I read a textbook from cover to cover. It's nice having work that's focussed enough to make it worth the investment. This was very accessible, but covered a fair amount of ground (at least it felt that way to me - I don't have much to compare). It was, at least, enough to springboard me from high schoolish level into a more specialised textbook with a fair degree of confidence. (I'm currently reading Christopher Chatfield's The Analysis of Time Series: An Introduction)

The Four Loves
C. S. Lewis

I read this and thought "Hmm, that's interesting, but there's nothing particularly mindblowing about it." But since then I've been remembering this quote or that idea in a bunch of different contexts. I'm not sure there's an exciting core message that the whole book works to convey - although it's all thematically consistent - but there are fascinating insights scattered throughout. I was a little disappointed that so much of the book seemed to address men only. I see Lewis's point that he doesn't have any other experience, but I still didn't like it. Nonetheless, this was an enjoyable and thought-provoking read.

A Skull in Shadows Lane
Robert Swindells

From the title, the back cover blurb, and what I've previously read from Swindells, I was expecting this to be a light-hearted five-find-outers-style mystery story. Instead it was a rather thoughtful look at post-WWII life through the eyes of eleven year old Jinty Linton, her brother Josh and their cohort, in a little English village where "nothing ever happens". I think Swindells exploits that ordinariness very well - this connected with me in a way that war stories generally don't. It felt like a children's book (which it is), but I still enjoyed it and have found a new way of seeing that time period.

Monday Miscellany

1. I posted recentlyish about knowing "nothing", largely prompted by the fact that some of the papers I'm reading for my honours project go way over my head. I also ended up emailing my supervisor to say "Wah! I don't know any stats!" (But in more grown up language, 'cause I'm boring like that.) He helpfully sent me an open source stats textbook. After reading about half of it, I was thinking "No, I know all of this. I meant the other stats." Oops. The second half of the book has been more helpful/new, but I suspect I'll need yet another book after that. So many things to know!

2. Easter was awesome. Easter is awesome. Something like that. And Easter hymns are amazing. Something in the music and the physicalness of really singing it out captures the wonder and excitement that is so hard to maintain through the year, but so much what Easter is about. He is risen! We are forgiven! He is risen!

3. In the sermon on Good Friday, our minister pointed out that Jesus was hated - and crucified - for showing love. I'm not sure how often I want to be liked more than I want to show love (and act on that). More often than I should. But at the same time it's definitely not right to alienate people. It's a tricksy topic, but one worth thinking about, I think.

4. I discovered that Google Reader was shutting down from my sister, who actually spends enough time on a computer (with internet) to use it regularly. I also discovered from her that there's a Feedly mobile app which works quite well. And now I have a feedreader on my phone (which, in fact, I really like). I haven't been so informed in months.

Theme Thursday: Celebration

For the first time ever, I have actually found a photograph that sorta-maybe-of course it does fits the theme for Theme Thursday at Clan Donaldson. Taken with the great technical knowledge required to operate my cellphone camera, here is Sir Laughs-a-lot being all celebratory about big trees. Or bored of me taking five trillion and two pictures. But it looks happy, right? So, huzzah! Also, those trees are really big. It's awesome.

Wordless Wednesday: Burst Pipe

So Very Little

I have been very busy lately, with the masses of stuff I'm trying to cram into my head. Formalisms quantum mechanics and principles of thermodynamics and methods of solution of partial differential equations are all buzzing around, needing to be learned before I write tests and just because they're useful.

Then I move to reading for my project and there are all sorts of more specialised things I need to know - everything buzzing around my head is not very much at all.

Marking first year undergrad work reminds me of how much I do know, though. More than the owners of the scripts now covered in red ink (at least when it comes to physics - there are other spheres of knowledge, I know). But the difference between what we know is so very very much less than the masses of things we don't (even just in the realm of physics). None of us know very much at all.

There's a continual tension between ignorance and opportunity. We would never have the joy and excitement of discovery if we knew everything - but there's enough we don't know to go on discovering as long as we care. On the other hand, ignorance in its own right doesn't seem awfully lovely. Somehow, though, I need to love my ignorance at least inasmuch as it gives me the opportunity to abolish it. It's an odd kind of not-quite-dichotomy.

Sunday Seven

I was going to write a Friday Five post, but I went to bed instead. Then I thought I'd replace it with Saturday Six, but, yeah, well, uh . . . Maybe I can get Sunday Seven to work.

1. My Wordless Wednesday post was all done on Wednesday, I promise. My phone just didn't feel like publishing it till this morning. I think I'll just call today an honourary Wednesday. That works, right?

2. Tomorrow I'm getting on a plane and flying to Grahamstown, where I'm going to sleep for a week. Except for the sleeping part, alas. I'm actually going to FameLab for a week, which is nearly as exciting a prospect.

3. The name "FameLab" makes me think of Harry Potter's first potions lesson, where Professor Snape tells his first years that he can teach them to "brew fame and bottle glory". Do you think I'd be allowed just a tiny sip of the Felix Felicitis potion before the final?

4. Yesterday Sir Laughs-a-Lot and I went to The Last Night of the (Maritzburg) Proms concert with the KZN Philharmonic Orchestra under Richard Cock. It was really awesome. Now I want to go to the opera. And learn to understand all - or at least more - of the technical musical stuff.

5. The concert was in the city hall, and while one might admire the clock tower as one drives down Commercial Road, that has nothing on the sense of being inside a work of art. Inside it! With a pipe organ the size of a small house! And ornamented everything! Oh my!

6. One of the topics I've been covering for my honours project is neural networks - a system that can be implemented on a computer and mimics the brain in learning to make accurate predictions. Neural networks are not awfully like human brains, really, but the way the technique was inspired, as well as the technique itself, is fascinating.

7. Neural networks are one of the topics I'm playing around with using in the FameLab finals. If I don't do that (or maybe even if I do), perhaps I should write up a similar kind of description to put on here. Because I won't, you know, be trying to frantically catch up with my lectures before the slew of pre-Easter break tests. It would be fun, though.

Savo 'lass a lalaith.

Wordless Wednesday: Two for One (Playing Catch Up?)