A light puzzle

Here's a puzzling photograph that Hans Bachor showed me at the end of the NZ Institute of Physics conference last week. It comes from his public lecture on lasers a week ago. And we don't have the answer to it, so maybe you can enlighten us (pun intended).  The photo is of a demonstration of […]

Continue reading

NZIP2015 Highlights

So the NZ Institute of Physics conference is in full swing. I have a bit of a break between the end of the last session and tonight's conference dinner, so there's time to give some highlights so far.  Well, first, the low-light: Like the rest of my family and half of Hamilton I've had a […]

Continue reading

The equation of time strikes again

Some of us are rather looking forward to getting to 22 June. That's when the days get longer again. Yes, the reality is that no-one's really going to notice much difference for a while, but it's encouraging to think that the days will be getting lighter again, if only by a little bit. Don't confuse […]

Continue reading

Lenz’s law – at 3 tesla

When I was at school, and introduced to magnetic fields in a quantitative sense (that is, with a strength attached to it), I remember being told that the S.I. unit of magnetic flux density (B-field) is the tesla, and that 1 tesla is an extremely high B-field indeed. Ha! Not any more. Last Friday night […]

Continue reading