Marcus Wilson

Dr Marcus Wilson is a lecturer in the Engineering Department at Waikato University and author of the Physics Stop blog. His current research involves modelling of the electrical behaviour of the human brain during natural sleep, focussing particularly on the transitions between sleep states. Previous research interests include infra-red physics and signature control (stealth) and quantum Monte Carlo methods. He graduated from Cambridge University in 1992 (BA Hons) and completed his PhD at Bristol University in 1995.

The numbers are the numbers, except when they’re not. - Physics Stop

Feb 14, 2020

I’m not quite sure of what to make of the new figures for COVID-19 (as we must now call the novel coronavirus – though I’m not sure the capitalisation is correct) from Hubei province: Image from  The spike yesterday is a consequence of a using a different way of defining a case – one based on a clinical diagnosis (i.e. someone has the symptoms) rather than a definitive test. There’s sense in that, but it does make for a mess when one tries to interpret trends in what is going on. Moreover, with only Hubei province using this new method, data from China seems now to be reported using two different standards. This can’t make it easy for researchers into COVID-19. Maybe more worryingly though, from a science perspective, are the reports that two senior Hubei officials were sacked … Read More

The swimming pool paradox - Physics Stop

Jan 24, 2020

It’s another warm day, but the breeze isn’t helping much, so off I go to the inviting outdoor swimming pool (banner picture) at the other end of campus. It’s an unheated pool (well, there’s no artificial heat source), which means one thing: It’s going to feel cold when I get in*. I should just jump in and get on with it, but that’s easier said than done when you know what the temperature is like. Eventually, I get in (brrr!) and have a good swim, by which time I’m not feeling so cold anymore. But I can’t stay in all afternoon. Work to do. So it’s time to get out. And here’s the total injustice of it all. When I get out I feel cold as well. That’s just not fair. It’s cold when I get in, and cold when … Read More

BIG idea physics - Physics Stop

Jan 21, 2020

This morning I’ve been having a quick look through some documentation from The Ministry of Education on proposed changes to NCEA Level 1 Science. For those not familiar with the NZ secondary education system, a typical student would complete NCEA level 1 at the end of year 11.  In this regard, it’s broadly similar to the English GCSE process, though there are plenty of unique features about NCEA. Anyway, NCEA is in the midst of a big review process, and the Ministry of Education is releasing draft documentation on various aspects. One that’s up for discussion is Level 1 Science. There’s been quite some detail put into the documentation (available right here – have a look!). The proposals talk about weaving “Big ideas about Science” with “Big ideas of Science“. The Big Ideas about Science concerns how … Read More

What a difference the decimal point makes - Physics Stop

Jan 13, 2020

I’m back at work following a nearly three-week break over Christmas. We were fortunate to be offered a house to stay in for a week over Christmas, which enabled us to have a holiday in Dunedin and see the extended family reasonably cheaply. But the house came with a catch:  a small, old, cuddly, ball-of-fur that needed daily medication. Amazingly, this kitty was completely compliant when it came to taking her medicine, unlike our own cat of many years ago. We had written instructions from her owners – she was having a gel-like medicine that you rub into the inner surface of her ear. Pre-loaded syringes full of the stuff were supplied – we just needed to put the right amount onto a fingertip (wear gloves or you medicate yourself as well as the kitty-cat), rub it into her … Read More

Anti-neutrinos–When you are your own opposite - Physics Stop

Nov 28, 2019

Around a million billion pass through you each second, almost all originating from our sun, but few of them are likely to interact with you enroute. I was reading in a physics magazine earlier in the week about the nature of neutrinos. These are extremely numerous elementary particles, but only interact very weakly with anything.  A typical neutrino will travel through space for many many lightyears before it interacts with anything.  Consequently studying neutrinos is pretty tough science. There are a few experiments in the world to detect neutrinos, such as the IceCube detector at the South Pole (Don’t you love the name?) Here’s Jenni Adams from the University of Canterbury talking about what it takes to detect them.   I first came across neutrinos in my undergraduate studies in a Particle Physics course. Here they were discussed in … Read More

Is car washing so bad we need to ban it? - Physics Stop

Nov 21, 2019

Apparently, some people enjoy washing their cars. Each to his or her own, I suppose. I mean, some people like duck shooting, some people follow Coronation Street, and some people’s idea of a good day out is to sit on a grass bank at Seddon Park and watch cricket all day. (Guess which one I’ll be doing a week Saturday…) Now, in the news last week was the new “ban” by Napier City Council on washing your car on the drive. I used this article in our Science Communication class on Tuesday as an example of how to dig a bit deeper and find the science behind a story. I told the students to imagine they’d been given half an hour to prepare for a local radio interview about the proposal, and to get themselves ready. It was a … Read More

How to cheat at university - Physics Stop

Nov 11, 2019

A couple of days ago I attended (and spoke at) the University of Waikato’s “LearnFest” event. There were lots of talks and sessions on very diverse aspects of teaching, mostly at tertiary level. One was by Myra Williamson from Te Piringa Faculty of Law here at Waikato, on Contract Cheating at Tertiary Institutions. Now, I was a very well-behaved undergraduate. I attended nearly ALL my lectures (in fact I missed just two in my three years, and those two because I was really sick), I did ALL my various assignments MYSELF, ON TIME, and even lending my lecture notes to a friend (who couldn’t be bothered to get out of bed and onto his bike for a 9am lecture on a minus 6 Celsius February morning) felt uncomfortable to me. The thought of getting someone else to write an … Read More

Twenty thousand leagues under the sea - Physics Stop

Oct 31, 2019

I’ve been reading Jules Verne’s novel Twenty thousand leagues under the sea, considered as one of the very earliest science fiction stories. In brief, Monsieur Aronnax and a couple of sidekicks are taken prisoner by Captain Nemo and his mysterious crew and treated to an underwater voyage around the world on the truly expansive submarine, Nautilus. They get to visit vast reefs, raid sunken galleons, speed through submarine tunnels, view underwater volcanoes and talk a walk (in full diving suit) through the lost city of Atlantis. Written in 1869, the novel gives an interesting picture of the state of scientific knowledge at the time, and how it might find an outworking in the future. One curious feature of the Nautilus is its power supply: Electricity. It’s worth pointing out that in 1869 thermodynamics was still young – only 25 years … Read More

Counting Barretts - Physics Stop

Oct 23, 2019

Just in case you don’t have a seven-year-old boy in your house (in which case this will be obvious) a well-known brand of breakfast cereal here in NZ is currently coming with All-Blacks stats cards. Perfect for finding out your favourite rugby player’s height, number of caps, and how much they can eat for breakfast. Buy a family pack and you get four cards. We now have way more whole wheat biscuits in our house than we are likely to get through before Christmas, much to the delight of the cereal company no doubt. What great advertising. Anyway, there are 40 different cards (current All Blacks plus some “all-time greats”) and an obvious question that sprung to the mind of my seven-year-old was “Wouldn’t it be amazing if I opened the pack and got all three Barretts (Jordie, Scott and … Read More

If you can’t measure it, does it exist? - Physics Stop

Oct 18, 2019

In the last couple of weeks, I’ve been busy preparing for our summer paper on Science Communication. Looking for something amusing about ‘risk’ in science, I came across this neat cartoon about why so many people come knocking on my door (or phoning me, or emailing me) desperately wanting me to spend hundreds of thousands of dollars proving their sensational, Nobel-prize winning, world revolutionizing, if-only-someone-would-fund-me, the-CIA-is-suppressing-it, utterly bizarre theory about quantum mechanics: Only this week I deleted an email along those lines that I just couldn’t face responding to.  Quantum Mechanics does, indeed, take a lot of maths to get to grips with in detail. In fact, it’s developed it’s own maths, in a sense. Try combining two particles of spin 1/2 and you get the result 0 and 1.  Half plus half = zero and one.  … Read More