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Betelgeuse, Gamow, and a Big Red Horse

There has been a lot of talk recently of Betelgeuse possibly going supernova this century or not...

Climate Change, the Walrus and the Carpenter

I have recently watched two videos on climate change by Sabine Hossenfelder.  The first one...

A Very Large Hadron Collider?

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Robert H OlleyRSS Feed of this column.

Until recently, I worked in the Polymer Physics Group of the Physics Department at the University of Reading.

I would describe myself as a Polymer Morphologist. I am not an astronaut,

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Warning! If you’re thinking this is going to be about gruesome punishments or such like, prepare to be disappointed! This is about teaching and learning electromagnetism.
Having read the biography of Oliver Heaviside, I remain aware that I am not really au fait with inductance as I am with resistance and capacitance.  Searching without much success for a textbook that would explain it in a way I could understand, I came upon A Treatise on Electricity and Magnetism - Volume 2 by James Clerk Maxwell.  Turning to the relevant section, my eye fell upon this:

“England is the paradise of individuality, eccentricity, heresy, anomalies.”
So wrote George Santayana http://en.wikipedia.org/wiki/George_Santayana in 1922.

Here we have two words, one in Arabic and one in Hebrew, which scholars of those languages will have no difficulty in recognizing as descending from the same ancient Semitic source. In Arabic the word means “error” in the sense of “error message” from a computer. The Arabic version is pronounced “khata” (with an emphatic “t”), and the Hebrew is quite similar.

I’m sticking with the Arabic for now, because this is the jumping-off point for an interesting bit of medieval mathematical history.
«There are two main ways in which policymakers are insidiously interfering with the usual rules of supply and demand for raw materials, and myriad different smaller ones. . . . One is the policy of ultra-cheap money in advanced economies to fight the economic crisis; and the other, more commodity-specific one, is massive public subsidy for the production of bio-fuels. Food is being elbowed out by pursuit of "clean fuel". »

So writes Jeremy Warner, Assistant Editor of the Telegraph, in an article entitled
Polyethylene terephthalate (PET) is the third most common synthetic polymer and accounts for about 18% of world polymer production. It is an aromatic/aliphatic polyester which possesses very practical thermal properties that are not found in the all aliphatic commodity thermoplastics polyethylene or polypropylene: a glass transition temperature (Tg) near 67°C and a melting temperature (Tm) of 265°C.   But like those two, it is derived from fossil fuels: the key aromatic component of PET, terephthalic acid, is derived from petroleum, while ethylene glycol is derived from petroleum or natural gas.