My most cited paper of the last two years is wrong

Academics are assessed in a number of ways, and one proposal that keeps coming up to assess us is via citations. The idea being is that if nobody cites your work (i.e. refers to your paper in their paper) you must be doing boring work, but if your paper is being cited by many others then it is clearly popular so must be good. And almost whenever someone suggests this, it is pointed out that papers that are obviously wrong can be highly cited, particularly if they are published in a prestigious journal. This is a fair point. For example Wolfe-Simon et al.‘s Science paper of 2011 has been cited over 400 times, and is clearly wrong, as a number of the citing articles state.

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Picking a language

One of the thorniest questions in the teaching of physics at degree level, is which computer language to teach. There is no consensus on this, and I am not sure that there will every be. Getting everyone to agree on the best computer language to teach at first year would be harder than getting everyone to agree on a favourite ice-cream flavour. However hard you tried there would always be one person holding out for pistachio.

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The News of Radio

“The News of Radio” was the title of a 1948 article in the New York Times that started “Two new shows are announced by CBS to serve as summer replacements for the hour-long Radio Theater on Monday evenings… “. Nine paragraphs later the article got round to announcing what arguably turned out to be the most important invention of the 20th century: the transistor. The transistor is the solid-state switch at the heart of the silicon chips in computers, mobile phones and indeed all the rest of modern electronics. I am not sure what it says about how societies in general or newspapers in particular, react to new world-changing technologies, but I think it is pretty funny that the announcement appeared in paragraph 10 of an article on page 46.

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Impact on the heart

One of my tasks in the department is to coordinate our preparation for the UK government’s REF2021 exercise. In 2021 the UK government will assess research (not teaching which is done separately) in UK universities. REF is hugely important, it determines real money, league-table position, and reputation — three things that really matter to universities. Which is why I am in meetings about this four years in advance :(.

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Google knows a lot, but it only just about knows that women do physics

CaptureI am tweaking (someone else’s set of) slides for a schools careers talk. Tomorrow Farnborough College have a careers day, and it is my job to tell the students about what physics degrees and careers have to offer. Most of the students will not have a scientist or engineer in the family, as I didn’t when I was their age. So they may have very little idea of what scientists and engineers do, or what careers science and engineering graduates do if they leave science and engineering on graduation, as many do. Tomorrow, I hope to demystify this, and help them make good decisions.

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The fox knows many things, but the hedgehog knows one big thing

Vulpes macrotis mutica with pupsThe title is a (translated of course) quote from Archilochus, a Greek poet from the 7th century BC. Somewhat randomly, this quote from a long dead Greek poet is very popular in the fields of data science and prediction. Nate Silver’s fivethirtyeight.com site has a stylised fox as logo in reference to this quote, although I don’t think he was the first to start using it. The quote is used to classify people, in particular those making predictions, into two groups: the hedgehogs and the foxes.

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Beautiful numbers

FA-18 going transonicA lot, maybe most, of the fun behaviour that occurs in physics is controlled by dimensionless numbers, i.e., quantities that don’t have units such as metres or seconds. These dimensionless numbers are typically ratios between two quantities. Each of the two quantities has the same dimensions (units) and so these units cancel, making the ratio dimensionless. There are many of them in physics, but perhaps the only one in common use is the Mach number — named after the German physicist Ernst Mach. The Mach number is the ratio between two speeds, the speed of an object, often an aircraft as above, and the speed of sound. When the Mach number is greater than one, the plane is supersonic, and when it is less than one the plane is subsonic.

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Dragon-kings, black swans and an anti-HIV drug

paris_dksornetteNext week, I am off to Paris for a workshop, so I am writing my talk. Above is a plot of French cities. The x-axis is the log of the rank of the city, where the ranking of the city is by size, i.e., the first point (shown in pink) is for France’s largest city, Paris, at an a x value of log(1)=0, while the second point is France’s second largest city, Marseille, at a value log(2)=0.30, the third is Lyon at log(3)=0.48, etc. The y axis is the population of the city, raised to the power c = 0.18. This value is a fitting parameter, the value of 0.18 is the one that makes the data closest to a straight line — as you can see for this value of c the data falls on a pretty decent straight line.

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