A mathematician can say what he likes… A physicist has to be at least partly sane J. Willard Gibbs What is it that makes a physicist sane (if only in part)? Everything has to be related back to the 'real world', or the 'real universe'. That is, a physicist has to talk about how things […]
Continue readingTag: light
Seeing spots before my eyes
"Doctor, Doctor, I keep seeing spots before my eyes" "Have you ever seen an optician?" "No, just spots". The concept of seeing an optician floating across my field of view is a scary one indeed. However, the concept of seeing spots doing the same is one I'm coming to terms with. I had a talk […]
Continue readingHawking radiation in the lab
A highlight of the recent NZ Institute of Physics conference was the Dan Walls medal talk given by Matt Visser. Matt has been working on general relativity. That's not desparately unusual for a physicist, but Matt has been successful in working on some of the crazier aspects of relativity and getting it published – wormholes, […]
Continue readingPrecision Cosmology – Yeah, Right!
We've just had our first session at the NZ Institute of Physics Conference. The focus was on astrophysics, and we heard from Richard Easther about 'Precision Cosmology' – measuring things about the universe accurately enough to test theories and models of the universe. We ablso heard about binary stars and supernovae, and evidence for the […]
Continue readingHotspot and Silicone Tape
Well, today’s big story is just perfect for PhysicsStop. Cricket meets physics. What more could I ask for. In case you’ve just arrived from Alpha Centauri, there have been accusations flying that both English and Australian batsmen have been trying to defeat the ‘Hot Spot‘ detector by putting silicone tape on their bats. The allegations […]
Continue readingWhat’s in a colour?
When I was young (about six-ish) I had a variety of ambitions. Some of them I shared with a lot of other boys of my age, such as being a train driver and playing cricket for England. Some were more particular to me, such as becoming a biologist and discovering a new colour. Needless to […]
Continue readingSeeing circular polarization
Physicsworld magazine is doing a ‘special feature’ this month on animal superheroes – those with rather unusual physical abilities. The best of the lot (in my subjective opinion) is the featured-on-the-cover mantis shrimp. Not because of its ‘dactyl clubs’ that can produce a force of 700 N, but because of its eyesight. The mantis shrimp […]
Continue readingPinhole cameras and eclipses
Well, the eclipse yesterday was fun. There were enough patches of sky between the clouds to get some good views. I was pleased that the pinhole cameras I made out of miscellaneous cardboard tubes, tins, paper and tinfoil worked really well. Also, the trees around the front of the sciences building gave some nice natural […]
Continue readingPepper’s Ghost
Have a good look at the photo. The pretty rhododendron to the left of the chair looks a bit odd. That’s because it’s a ghost shrub. No, our garden isn’t haunted, and neither have I doctored the photo; it’s an example of Pepper’s Ghost – an illusion caused by reflections. The bush in question is […]
Continue readingDistant galaxies and hobbits
I haven’t read ALL of Tolkien’s work, but I suspect space-travelling hobbits don’t feature anywhere. However, what do feature are hole-dwelling hobbits, and I had the fun of seeing their holes in the countryside near Matamata yesterday. The original set for Lord of the Rings was mostly removed after filming, and rebuilt for the filming […]
Continue reading