Cartoonist Scott Adams, creator of the comic strip Dilbert, is a climate change skeptic who repeats the well-worn anti-science tropes of that community. Usually he attacks the credibility of the climate change models that are used to predict the scale of climate change and the potential consequences. But in this cartoon, he goes further and seems to be attacking the whole idea of random statistical sampling.
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Obtaining the first-ever photograph of a black hole was an impressive feat. We tend to think of black holes as being tiny and they are. A black hole represents a singularity in space-time where gravitational field becomes so large that there is extreme curvature of space. But the ‘event horizon’ of a black hole, the region inside from which no light can escape, need not be tiny. It is the event horizon that gives rise to the dark region seen in the photograph and the size of the event horizon for any mass M is given by the Schwarzschild radius that is equal to 2GM/c2, where G is the gravitational constant and c is the speed of light.
The black hole at the center of the galaxy M87 that was photographed has a mass 6.5 billion times the mass of the Sun and thus its Schwarzschild radius is about 1.9×1010 km. This is quite large, about three times the distance of the planet Pluto from the Sun, which is 5.9×109 km.
Archeologists sometimes find ancient artifacts that show considerable sophistication. These might cause us to infer that the people of that time had a better understanding of the underlying science than we had previously given them credit for. This is because advances in technology often go hand in hand with advances in science. Technological advances upon up new frontiers for scientific investigation while new scientific theories lead to new technologies. But that link may not always exist.
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I do not suffer from jet lag that much but I have friends who suffer terribly. I ascribe my greater tolerance to my belief that a prime cause is tiredness during the long flight and so make it a point to sleep as much as possible on the plane, which I am fortunately able to do. Some people find it very hard to sleep and watch a lot of inflight films which may make the even more tired. I have also experienced that traveling west is easier than traveling east and I put that down to the fact that going west results in the day-night cycle becoming stretched out and so one has longer nights and can more sleep.
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There has long been a common method used in science and social sciences when deciding whether results are worth publishing. One starts out with what is called the ‘null hypothesis’, a kind of baseline that might represent (say) the current conventional wisdom, and then one sees if the results of the experiment are consistent with it. If it is not consistent, then the results are considered to be more interesting than if they were. This requires the use of statistics and then one has the problem of deciding whether the result is a real effect or a statistical anomaly. For a long time, something called the ‘p-value’ was used to make this decision and a p-value of 0.05 was used as the benchmark for statistical significance.
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The evolution of whales is one of the most fascinating stories in evolution because it goes in the opposite direction to the conventional story, of a land animal becoming a water-based one. The outlines of this have been pretty well established but now comes a report of the discovery of a new fossil of a large whale with four large legs that showed it to be capable of life on land and sea.
Photograph: A. Gennari/CellPress
We often see artistic representations of animals that have long been extinct. Some of these are in color, even though we only have the fossils. Fossil expert Maria McNamara explains how scientists try to infer their coloration. She says that they carefully study fossil metallic insects with hard shells that have preserved their color as fossils to see what makes them take on various colors. She says that if an animal’s skin layer is fossilized, that helps too. When it comes to dinosaur colors, she says:
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A lot of memes have been circulating drawing parallels with the awkward Brexit attempts by the British government, such as this one.
This sums up the UK trying to leave the EU #Brexit #BrexitVote pic.twitter.com/6hB9wdQCtz
— Raj Popat (@MrRajPop) June 25, 2016
I chose this one to highlight because the person seems to have a common misunderstanding that Galileo tried to clear up a long time ago about the nature of relative motion. Since the man was on the train, he had the same velocity as the train when he jumped off and hence was moving in the direction of the tracks when he hit the ground. It was not allowing for that that caused him to fall. If he had jumped more along the direction of the train’s motion and with a running action in that direction, it would have been much less jarring to him and may have managed to stay upright.
Not that I am recommending anything that dangerous of course!
Diophantine equations are a certain class of equations for which solutions that consist only of integers are sought. So, for example, we know that Pythagoras’s theorem x2+y2=z2 has many sets of solutions such as the numbers x=3, y=4, z=5 or the set x=6, y=8, z=10. A lot of these problems involve existence claims such as whether any solution exists at all and if none can be found, whether it can be proved that no solution exists.
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The Cambrian explosion is the name given to the discovery of a vast range of fossils of organisms that existed about 500 million years ago. The first discovery of them was made in the Burgess Shale region of Canada in 1909 and other troves were later found in China and Australia. But now comes a report of an extremely rich new trove that has been discovered, again in China.
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