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…]

Gary Marcus predicts that in a few decades, we may all not only have the option of traveling in driverless cars, we may even be obligated to do so.

Within two or three decades the difference between automated driving and human driving will be so great you may not be legally allowed to drive your own car, and even if you are allowed, it would be immoral of you to drive, because the risk of you hurting yourself or another person will be far greater than if you allowed a machine to do the work.

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I am not a fan of practical jokes. They are often cruel rather than amusing and it is not fun when one person is the victim and is being laughed at by others. Sometimes they can be excused because they cause just minor embarrassment but this too is dangerous because what can seem like something minor to the perpetrators can be traumatic for the victim. [Read more…]

Two dogs explain the different types of chemical bonds that form between elements.

My one suggestion for improvement is that the partner to a ‘cation’ should be a ‘dogion’ instead of the traditional ‘anion’.

(Via Maggie Koerth-Baker.)