It is not uncommon to find correlations in the behavior of two or more phenomena and such correlations are sometimes used to imply causation. One of the most common objections posed to such arguments is that ‘correlation does not imply causation’, and is one of the first things that people learn about statistics. Even if they have not studied the subject, many people know enough to able to bring up this objection. But people may be sometimes too quick to pull that trigger.
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Tom Yulsman writes that we are seeing truly weird behavior in the Arctic region, with temperatures in some areas soaring 35^oF (20^oC) above the norm.
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Tattoos are becoming extremely common. I do not mean some little symbol discreetly placed on a small part of the body but even massive ones that cover much of it. I do not have a tattoo and have no intention of ever getting one, since I belong to a generation (and grew up in a country) in which no one I knew got tattoos. To the extent that one read about who got them, it was mainly sailors in western countries who, like Popeye, got clichéd ones with anchors or hearts with arrows through them or women’s names. The creepy 1969 film The Illustrated Man based on the Ray Bradbury story collection of that name may have cemented my antipathy to them.
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Michael Faraday (1791-1867) is one the greatest scientists of all time and his contributions to physics and chemistry are immense and his name can be found associated with all manner of phenomena. The unit of capacitance known as the ‘Farad’ is named after him. Amongst all his contributions to science, perhaps the one that had the most impact on the public was his discovery of the law of electromagnetic induction, that if a wire and a magnet are in motion relative to each other, a current will flow in the wire. This forms the basis of our public electricity systems and the working of electric motors.
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I have very vivid dreams, many of them, each and every night, some of which the details I remember after I wake up, though others quickly fade from memory. It turns out that everybody dreams during the REM (rapid eye movement) period of sleep but not everyone recalls those dreams on waking up, so the difference between people who say they dream a lot and those who claim to dream a little or not at all lies only in the recall of them. According to Susan Blackmore in Consciousness: A Very Short Introduction (p. 99), “In a typical night’s sleep the brain cycles through four stages of non-REM sleep; first going down through stages 1-4, then back up to stage 1, and then into a REM period, repeating this pattern four or five times a night.”
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As someone who has family in Sri Lanka and New Zealand, this necessitates periodic long flights. Fortunately for me, I do not suffer as much from jet lag as some others do. I am usually back to normal within a day of arrival at my destination whereas I have friends who take up to a week. My personal hypothesis is that the after-effects of jet lag are caused largely by tiredness due to lack of sleep. As a result, on these long flights, I ignore all the in-flight entertainment and instead spend as much of my time as possible sleeping, only waking up to eat or read. Fortunately I can sleep seated.
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In an earlier post, I linked to a test to see how good we are at recognizing faces. There is also software that takes measurements of parts of the face that are supposedly highly distinctive (such as the shape of the ear) and uses that data to find points of similarity to give estimates of the likelihood of an exact match.
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I came across a paper that looked at the vexing question of why we so often spill coffee when walking with a cup of it, and what might be done to prevent it. Of course, coffee shops give us lids but quite often we use actual mugs that do not come with lids. The research was stimulated when a physicist at a conference watched his colleagues walk gingerly while holding cups of coffee and started wondering about it.
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