An outrageous laminar flow video

You have got to see this… This movie is a demonstration of laminar flow. My colleague Julia Mullarney used it last week in our Osborne lectures to high-school students to demonstrate what turbulent flow ISN'T. Basically, laminar flow is time-reversal invariant. This implies a few things, but, notably here that if you reverse the processes […]

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Probability madness

Probability crops up in many places in physics, not least quantum mechanics and statistical mechanics, where we are only sure of things in an average or 'statistical' sense. Dealing with probabilities can be a headache for many students. They are also a headache for many in everyday life. There are numerous occasions where we need […]

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The Australian Synchrotron

I didn't actually intend to visit the Synchrotron. I didn't actually know it was right next door (honestly – I don't exaggerate) to the Centre for Biomedical Imaging at Monash University in Melbourne until I arrived there on Monday. Somehow I managed to get myself tagged onto a tour with a group of students. The […]

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Every square millimetre counts

Seen on a notice at a Cambridge Cafe: Waipa District Council. Permit to occupy pavement space. This is to certify that **** has been approved to occupy 15.000000 metres squared of pavement space.  I might not have got the exact words right, but I certainly counted the number of zeros after the decimal point.  The […]

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The universal joint

…No, it isn’t something everyone smokes… But it is common in machine mechanisms. The universal joint is a neat way of turning rotation in one plane into rotation in another. A common use is on driveshafts where you want the direction of the shaft to bend. There’s a neat animation on Wikipedia of how the […]

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The storm surge

I shudder to think what it must have been like in the path of Cyclone Winston. It is hard to conceive of winds 230 km/h sustained for minutes at a time. I remember vividly what is now known as the Great Storm of 1987 (an extra-tropical cyclone) which pulverised south-east England on 15/16 October 1987. There […]

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The problem with science communication

Yesterday I was part of a very interesting workshop on Science in Society, in Auckland. There was a plethora of good examples of science communication discussed – including forest restoration on the East Coast, biological control of pests in vineyards in Canterbury and improvement of health outcomes for Native Americans in Montana. For me, it […]

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Gravitational Waves

The big breaking physics news is the detection of gravitational waves. These waves are distortions in space-time, caused by a large mass doing something spectacular (two colliding black holes in this case)  that propagate across the universe and create tiny changes in space when they reach us. The commentary here describes what goes on. Essentially, […]

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