Jet lag asymmetry

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.
[Read more…]

Calls to end use of statistical significance

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.
[Read more…]

A new stage in whale evolution discovered

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

[Read more…]

The color of prehistoric animals

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:
[Read more…]

Brexit memes and physics

A lot of memes have been circulating drawing parallels with the awkward Brexit attempts by the British government, such as this one.

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!

Solution found to problem involving the sum of three cubes

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.
[Read more…]

Rich new trove of Cambrian fossils found

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.
[Read more…]

Book review: Beyond Weird: Why Everything You Thought You Knew About Quantum Mechanics is Different by Philip Ball

(My review of the above book just appeared in the March 2019 issue of the American Journal of Physics (vol. 87, issue 4, p.319). You can access it here but I give the review below.)

A major problem with quantum mechanics is that the dominant Copenhagen interpretation is not conducive to providing visual images of what is going on. With special and general relativity, the initially unsettling ideas that time and distance are not invariants but depend upon the state of motion of the observer and that space can be warped by the presence of mass and energy have gone mainstream. Not so with quantum mechanics. Although of the same vintage as relativity, quantum mechanics has continued to greatly perplex people because it undermines the realist position that other theories, including relativity, take for granted, of a world existing independent of the observer, whose features we can discover by making observations. The denial of this made even Einstein uneasy.
[Read more…]

The Middle Ages and the periods before and after

We all have in our minds short histories of how knowledge grew and a popular one is that there was a period of scientific and philosophical growth that began more than a couple of millennia ago with the ancient Greek, Arabic, and Chinese civilizations that slowed down sometime during the early second millennium where there were no real advances and indeed a regression with a loss of knowledge. That was then followed by the period we now call the Age of Enlightenment with its associated scientific revolution that began in the 17th century around the time of Galileo. Scholars of the much-maligned middle period that has come to be down as the Middle Ages (or more pejoratively the Dark Ages) take umbrage with characterizations that compare that period unfavorably with what existed before and what came after.
[Read more…]

Students call for global strike to demand action on climate change

The revulsion over the mass murder of Muslims in New Zealand by white supremacists has overshadowed an important news event today and that is the call for a global strike by students to call attention to the need for governments to take action on climate change. They are rightly pointing out that it is their generation and those that follow who will have to live with the consequences of inaction by my generation.
[Read more…]