Wednesday, October 13, 2010

ZOMG CHEM 400

A little while ago I put together a presentation which gathers/scatters some of my thoughts on teaching chemistry in the 21st century for a learning and teaching symposium, which my colleague Dr Erica Smith very kindly presented for me while I was on long-service leave.

If you are at all interested, you can go here for a link to the first draft.

Erica tells me it went very well, though there was an interruption from the audience when I referred to non-scientists as 'muggles'; one gentleman apparently took exception to being called a muggle. Though I still think this is a perfectly valid characterisation - scientists are (1) the people who understand what is really going on, and (2) those who have the power to influence their environment in a meaningful way - I have removed it in the second draft. Muggles cannot help being muggles, after all, whereas it is open to everyone to learn to think in a scientific way.

***

September 16th 2011:

I thought I would just add the slide for the Conclusion in the powerpoint presentation of this and the accompanying text I sent to Erica...


"Chris put this line of untranslated Greek in on purpose and not (just) to show off.
Until recently, this was part of the common body of knowledge expected of an educated person in our civilisation: educated people would know a little bit of Greek and recognise this as a saying of the philosopher Heraclitus.


Now, anyone who sees it, whether they are educated or not, can look it up on Wikipedia. Chris doesn’t have to tell you what it means. It is pathetically easy for you to look it up so if you have the will to know you can go and do it.


(NB: If anyone asks about the years 1900-2000, you can make derisory comments about the ‘Age of Stupid’ … that was what I was going to do.)"

Sunday, June 27, 2010

Image Results for Chris Fellows

Of the Chris Fellowses in the world, the one with the largest web footprint is possibly the South African wildlife photographer known for his action shots of great white sharks. So if you google me you are likely to get results like this:


("So, Mrs Jones, number four is the man you say pulled your husband from his surfboard and bit his leg off above the knee?"
"*sniff* Yes, Officer... I'd know that face anywhere... *sniff*")

Best. Exam. Ever.


This is a reproduction in its entirety of my favourite exam of all time. It was for one of three coursework units we had to do in the Honours year and Dr Ken Adam had given me three books to read at the beginning of the year- one on Ab Initio Self-Consistent-Field Theory, one on Semi-Empirical SCF methods, and one on the application of computers to chemistry in general, with instructions to read them, except for one chapter in the last one. (Of course that chapter was about spectroscopy of molecules in interstellar space which was wildly exciting so I read it anyway).

Thursday, May 27, 2010

In praise of Control+C

Paper 1: Important for the transfer of energy and matter across the ocean/sea air interface are some parameters called the roughness length, z0, and the friction velocity, U*, of the interface that can be determined by measuring the velocity of the sea air at various heights above the water and fitting an equation, like so:


In 1969 a group of scientists from the Massachusetts Institute of Technology went out and did a bunch of measurements like this. They looked at the variation in z0 and U* as functions of U10, the air speed 10 m above the ocean surface. They took 299 separate wind speed profiles, binned by U10 like so:


From which they got the following graph for U* vs U10 :


And the following graph for z0 vs U10:


Now, the values in Fig. 3 and Fig. 2 come from the slope and intercept, respectively, of equation (1) fitted to the same data. So I don't know why they didn't put error bars on this second graph or why they drew such a wacky line through the data points, since they didn't have Excel with 'draw a stupid non-physical line through the points' as a default option.

Paper 2: When they were sailing near Block Island this same group of scientists also did some more experiments where they poured oil on troubled water and took the same measurements, which they reported in another paper. This paper only has a graph for z0 vs U10:

And here they have only shown the trend line for the non-oil data because this paper was concentrating on explaining the oil data. They explained the difference between the oil data and the non-oil data using one model and not long afterward another scientist put out a paper (in Science, so no slouch of a paper) giving a different explanation for the difference.

Paper 3 (Science): The data presented in this paper (and cited as coming from Paper 2) looked like this:

Note that the data points that are from Paper 2 are exactly the same, but the data points that are not actually shown in Paper 2 (and are presumably from Paper 1) have wobbled around quite a bit. Paper 3 doesn't say so, but it is possible that all the points in these two plots that aren't the published points from Paper 2 come from the data used in Paper 2 but not shown (and hence for the no-oil curve, the same as Paper 1) Note that the positions of the open circles in the open circles in the z0 graph are actually quite different between Paper 1 and Paper 3, which suggests to me that the author of Paper 3 got hold of the raw U(z) plots for Paper 1 and re-fit them to the first equation we thought of.

Paper 4: Now for the fun part. This is from a much more recent review paper.

Exhibit 1:
This is cited as being 'after Paper 1 and Paper 2'. Sure enough, it is the data from Paper 2. But it isn't the data from Paper 1. It's the silly fitted line shown in Paper 2 with spurious data points added in crayon! How lame is that?

Exhibit 2:

This is reported as being 'data collected by [author of Paper 3] (after Paper 3)', as if it is a totally independent experiment!

...


This sort of thing could have been avoided if people in earlier decades had the ability to scan papers they were interested in and cut and paste bits of screenshots of them, like I've been doing.

FWIW this is what I reckon the curves should look like, drawn on the figures sourced from Paper 3 as they appear in Paper 4 - suspect points flagged from having big error bars and lying way off the U* trend-line as reported in Paper 1:

Sunday, May 16, 2010

"Any unauthorised use is strictly prohibited"

Here is a totally unauthorised reproduction of a seminar notice from the University of Sydney. It seems to describe a philosophical goal devoutly to be wished, with which I am in complete agreement:


SCHOOL OF PHYSICS COLLOQUIUM


Monday 17th May, 2010 at 3:15 pm

refreshments from 3pm

Venue: Slade Lecture Theatre, School of Physics

Title: Quantum foundations research @ Sydney

Presenter: A/Prof. Stephen Bartlett
University of Sydney

Abstract:

Despite a century of development since Einstein's explanation of the photoelectric effect, the foundations of quantum physics remain mysterious and surprising. Rather than accept the strangeness of quantum physics as a necessary evil, the research group in Quantum Foundations here at the University of Sydney is attempting to uncover the meaning and interpretation of the mathematical structure of quantum physics in terms of understandable concepts based on an external reality.

In this talk, I'll provide an introduction and overview of the Quantum Foundations research group here at Sydney, which includes researchers in Physics, Philosophy and HPS as well as a large-scale collaboration - the Perimeter Institute-Australia Foundations (PIAF) project.



The email concluded: "This email plus any attachments to it are confidential. Any unauthorised use is strictly prohibited."

So come and get me, seminar programme Nazis. :(