Physics is all about describing physical quantities. Whether it’s length, velocity, force, electric current or heat flux, it takes physics to describe what it is and what it does. Central to this is our system of units. The three really common base units (in the S.I. system) are the metre (unit of length), the second […]
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Three heads are better than one
It’s often surprising how different people can bring different approaches to the same problem, but in a way that gets you moving forward. I experienced a good example last week. A PhD student has been tangled in a nasty net of circuit analysis, trying to understand how a particular circuit does what it does. I’ve […]
Continue readingThe wonderful logarithm (or blog on log)
I’ve been marking a couple of student assignments today. I won’t go into the details, but as part of it they had to process some data and plot some graphs. The graphs showed values that varied considerably – some thousands of times bigger than others. I had expected (assumed = bad move) that the students […]
Continue readingI hate statistics
A week or so back I walked into the lecture room to give a lecture on electromagnetic waves, and was promptly asked: "Marcus, how much statistics do you use in your research?" My initial reaction was to think "what has this got to do with electromagnetic waves?" and then, realizing that clearly it had nothing […]
Continue readingCorrelation or no correlation?
Here’s an example of how easy it is to see things that don’t exist. It’s from a real piece of research (mine). As way of background, I’ve been doing some work with computer models of neurons in the cortex (NB this isn’t artificial neural networks, which were all the rage in the 1980/90s). Broadly speaking, I’ve […]
Continue readingBessel functions
I vaguely remember the following conversation from back when I was a PhD student. Student A: What’s a Bessel function? Student B (waving his arms about): It’s a wavy thing – goes like this, doesn’t it? Me: Sounds vaguely familiar – I think we did it in third-year. Student A: But what IS it? Me: […]
Continue readingThe sock monster
As I’m sure is the case in your house, socks go missing on a regular basis. You’re sure that every night a PAIR of socks goes into the linen basket, and that when the washing is done ALL its contents go in the machine, but, once things are dried and ready to go back in […]
Continue readingForces and other tedious stuff
I am a bit concerned over the attitude of the kiwi guy interviewed on CloseUp tonight, as he prepares to defend his home in Cairns against Yasi in a house 4 metres above sea-level when a 5 metre storm surge is predicted. You do the maths. Let’s pray that destruction is just limited to things that […]
Continue readingMirror trickery
Last week I heard about for the first time something that is common knowledge to all women in the western world – namely that women’s clothes shops use convex mirrors to make you appear thinner. Since I don’t frequent women’s clothes shops particularly often (I don’t frequent men’s clothes shops more than is strictly necessary, […]
Continue readingAnalogue Computing
What a dismal and predictable start to the Ashes. Turn your back on the computer screen for five minutes and suddenly England have lost three wickets. Anyway, yesterday I was in Auckland, talking about research progress with a group that we’ve had strong links with in the past. (By ‘we’ I mean the Waikato cortical modelling group). One […]
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