Monday, August 29, 2011

Common Sense in Science

"Common sense is the collection of prejudices 
acquired by age 18." —Albert Einstein

Did Albert Einstein have common sense? It depends on your definition of the term. Einstein once said that common sense is the collection of prejudices acquired by age 18, so by that definition, he did not. But in science, common sense is not all that useful because it is limited to the familiar world around us. It has been said that humans live in the middle world because our senses are limited and do not allow us to experience extremes. We cannot fully comprehend the very large (stars, galaxies), the very small (atoms, subatomic particles) or the very fast (the speed of light) to name a few examples. So when trying to tackle a difficult problem, common sense is more likely to get in the way than help solve the problem. As scientists, we need to rely on deduction, logic and evidence. 
  Einstein proved that time is relative when common sense would tell us that time is absolute and unchanging. That’s because on the scale of measurement that humans are used to, we can’t distinguish the tiny variations in time due to the effects of gravity or acceleration through space. Yet our world depends on it. Global positioning satellites have to constantly correct for relativistic effects because of their high velocity and the effects of Earth’s gravity. Otherwise they would be hopelessly inaccurate within a few hours. 
  Likewise, quantum mechanics challenges our common sense. Even Einstein had a hard time believing its core prediction that at small atomic scales, reality becomes a cloud of probabilities—even though his Noble prize winning work on light quanta in 1905 laid the groundwork for quantum mechanics. Over the last century quantum mechanics has perhaps been the most successfully tested theory in all of science.
  It is true that Einstein did not like to wear socks. After all, they would just get holes in them. And that he did not know his own phone number since it was easier for him to just look it up in the phone book. Once, as Einstein and a colleague walked together they notice an unusual plant growing along a garden walk. The colleague asked Einstein if he knew what the plant was. Einstein didn’t, and together they went to find the gardener to ask what it was. The gardener told them that it was a green bean plant. So now, if someone asks you if Einstein had common sense, you can tell them “Thankfully, no. And he doesn’t know beans either!”

Saturday, August 13, 2011

The NSF Science Survey

Do you think you know more about science than the average American? Since you're reading this, my hypothesis is that you do. Let’s test it by taking the following survey that was originally given as part of the National Science Foundation’s 2006 study on the public’s knowledge of science.*
I will include your results (anonymously) in a future column where I analyze both the questions and answers, and compare them with the results from the original survey. Have your family and friends take the survey as well—the more that take it, the more accurate the results will be.

*NSF Poll # 2006-SCIENCE: Trend Dataset--Surveys of Public Understanding of Science and Technology. The Roper Center for Public Opinion Research Data Archive was the data distributor.

Monday, August 8, 2011

Mountain Goats and Telescopes

Mountain goats seem friendly to tourists, 
but really they just want to lick our sweat!
Today we will finish up our previous discussion of Mount Evans in Colorado. Travelling to the summit at 4,300 m we pass through montane and subalpine life zones before reaching the alpine zone. The largest mammal found in this high-altitude habitat is the Rocky Mountain goat, which are actually members of the antelope family. They are only found in North America, predominantly in the Rocky Mountains and the Cascade Range. They eat the abundant grasses, sedges and lichens found at this altitude with little worry about predators such as wolves or bears which are at lower elevations. The only predator they have to contend with at this elevation are golden eagles which can threaten their young.
   Mountain goats are primarily an alpine/subalpine species, remaining above or near the tree line for most of they year, but occasionally travelling to lower elevations. In winter they descend to lower elevations to find protection from the harsh winter elements and to obtain essential mineral nutrients by visiting natural salt and mineral licks that have become exposed by the winter weather. In the summer the goats are attracted to the summit tourist sites because they can lick the salts left behind by sweaty park visitors!
   They are excellent climbers and prefer to live on steep cliffs where few predators will follow. They have specialized split hooves that have a hard outer lining with soft, rubbery pads and dewclaws for extra grip. They have two layers of fur to protect them from the elements: a fine dense undercoat of wool and an outer layer of long hollow hairs.
   Mountain goats can be aggressive, but not usually towards humans. The billies will fight amongst themselves during breeding season and the nannies will fight with each other for herd dominance or to protect their kids.
   Also located near the summit of Mount Evans is the world’s third-highest telescope, the Meyer-Womble observatory. Operated by the University of Denver, its relative isolation and location east of the continental divide provides drier, less cloudy and less windy conditions compared to typical resort climates near Denver. Researchers use this telescope to study cosmic rays. Cosmic rays are high-energy charged particles that rain down on the Earth at nearly the speed of light before smashing into atoms in the upper atmosphere. Some by-products from these collisions reach the surface of the Earth resulting in a charged atmosphere or interacting to creating biologic mutations. We are normally shielded from these cosmic rays by our dense atmosphere at lower elevations, but the thin air at the summit does not offer the same amount of protection, making it an ideal location to study them.