Tagged: maths

Password entropy - Physics Stop

Marcus Wilson Apr 30, 2014

As part of some 'NetSafe' training, I was shown this lovely xkcd cartoon http://xkcd.com/936/ .   Password entropy. That's a good way of putting it. The statistical mechanics definition of entropy would be k ln W, where k is Boltzmann's constant, W is the number of permutations possible, and ln is 'the natural logarithm'. Higher entropy, means … Read More

When stationary is fast - Physics Stop

Marcus Wilson Jan 17, 2014

One of the great lines on the cult BBC show 'Red Dwarf' goes (approximately, from memory) like this: Can't you go any faster, like so we're not being overtaken by stationary objects? I'm sure my youngest sister would be able to correct the wording, and tell me immediately which episode it's from, who says it to whom … Read More

The earth’s magnetic field: much more complicated than you might think - Physics Stop

Marcus Wilson Nov 13, 2013

At the recent NZ Institute of Physics conference, we were treated to a wonderful description of the earth's magnetic proceses, by Gillian Turner.  What makes up the earth's magnetic field? What effect does it have? How is it changing? At first glance the magnetic field of the earth is pretty straightforward. There's a magnetic north pole … Read More

Version control - Physics Stop

Marcus Wilson Aug 16, 2013

I've commented before that there are a lot of skills that our science graduates need to have, that don't get explicitly taught at university. That's because they don't neatly fit into compartmentalized degree courses where the structure is dictated by ... Read More

Dishwasher dynamics - Physics Stop

Marcus Wilson Jun 26, 2013

How long does it take you to load the dishwasher? Placing all those tricky-shaped objects in position to maintain the perfect balance between getting the maximum numbers of objects into the machine and placing them so that they clean optimally. Mo... Read More

Quantum mechanics: Reality is back - Physics Stop

Marcus Wilson Jun 14, 2013

With an exam imminent, I've had a queue of students outside my door wanting help with their quantum mechanics. This semester, they've come across the Schrodinger equation and the wavefunction for the first time and, unsurprisingly, some are struggling to grasp it. "But what IS the wavefunction?", they say. "How do you derive the Schrodinger equation?"Very good questions. While we … Read More

Is maths real? - Physics Stop

Marcus Wilson Mar 21, 2013

 A friend has just started a Bachelor of Arts degree here at Waikato. As part of her first year study, she's chosen to do a Philosophy paper. Apparently, one of the questions that has been posed, is "Is maths real?". Well, what is real? You certainly can't put 'maths' in a box and give it to someone. like you could with … Read More

Don’t underestimate the estimate - Physics Stop

Marcus Wilson Mar 15, 2013

 A few weeks ago we had a small, informal competition in the department - guess the maximum gradient on one of the roads on campus.  I think the motivation for this this small stretch of hill (or what passes for a hill here in Hamilton) was going to be used as part of a dynamics experiment, and so one of … Read More