When I first started teaching at CWRU over twenty years ago, I recall giving a physics final exam in which students wrote their answers in the familiar blue books. When I started grading them later, I found one in which the student had made little or no attempt at answering the problems. Instead he had spent the entire time sketching quite elaborate drawings of guns firing and other violent images for page after page. At that time, there wasn’t the heightened sensitivity to violence on college campuses that there is now and no training to be alert to such warning signs, and so apart from giving the student a zero on the exam, I did not do anything. [Read more…]

The words faith and belief obviously have a natural home in religious discussions. Should scientists avoid using such words, as in statements like ‘”I believe in the theory of evolution” or “I have faith in the law of gravity”, since that seems to put them on a par with “I have faith/believe in god” and enables religionists to claim that scientific theories are similar to religious beliefs? In a recent comments section, a recurring suggestion came up that in order to avoid this misapprehension, we should avoid use of the words belief and faith altogether in scientific discussions. [Read more…]

As the folks at They Might Be Giants remind us, when we want to learn reliable facts about the world that improve out lives, we turn to science.

So what has god done for you recently?

Watch this video of a cheetah running at full speed, taken with a high-speed camera. Note particularly how the head is held so rigidly fixed while the rest of the body goes up and down, no doubt as a result of the need to focus so intently on its prey. [Read more…]

The speed of light is the biggest barrier to the dream of intergalactic travel and the chance that we might ever encounter extraterrestrial intelligent beings. Faster than light travel has been the Holy Grail of scientists and science fiction writers and indeed of anyone who dreams of visiting distant stars and galaxies. After the recent unfortunate premature hype over the claims of faster-than-light neutrinos, I thought that we would not hear of such claims for some time. But it appears that scientists at NASA have been working on an idea that would enable faster-than-light travel. [Read more…]

The theory of evolution by natural selection says that changes come about incrementally, as a result of the long-term consequences of small selection advantages for favorable traits. The selection advantage is measured by differential rates in the production of offspring. If organisms with a new and favorable trait produce 101 offspring for every 100 produced by the older forms, the selection advantage s is said to be 0.01. The changes produced by even such a small reproductive advantage can be quite dramatic. If we start with a trait that is present in just 0.1% of the population and if this has a small selection advantage of size s=0.01, this variety will grow to become 99.9% of the population in just under 1,400 generations (in the codominant mode of selection) which is a very short time on the evolutionary scale. (Molecular Evolution, Wen-Hsiung Li, 1997, p. 39) [Read more…]