The Skeptical Teacher

Musings of a science teacher & skeptic in an age of woo.

Why Science Matters

Posted by mattusmaximus on January 13, 2009

Sometimes I have to deal with this very question from my own students: “Why should I care about science?” It’s a good question which deserves a well-reasoned response.

Science forms a critical part of our society. Many people can understand the importance of science in relation to technological development – such as the creation of new vaccines every year to deal with the annual influenza cycle, for instance. When people can see the direct application of science to their immediate lives, then it is easy to justify the resources necessary to pursue such scientific work. I often like to say that people have no problem with building a better I-pod and the research that goes with it.

I’m not talking so much about building a better I-pod (though they are very cool). I’m talking more about both the process of scientific thinking as well as the pursuit of pure (or theoretical) science.

Think about it – you are reading this blog post on a device that is the direct result of purely theoretical scientific investigation by individuals who had no notion or motivation to create computers or the Internet. Let me give you a little history lesson…

Around the end of the 19th century, many scientists believed that purely theoretical science was nearing its end. That is, they thought that through the process of science we learned all there was to learn – the rest was simply filling in details, or, as one put it, just getting experimental results to more and more decimal places. Throughout the 1800s, the development and rise of science using methodological naturalism as its method yielded astonishing advances in every field – biology, geology/earth science, astronomy, physics, chemistry. I’ll speak specifically about physics, since that is my area of expertise.

The cornerstones of 19th-century physics were classical Newtonian mechanics, Maxwell’s electricity & magnetism, and thermodynamics. Many physicists of the day thought that with these crown jewels of theoretical physics, we’d figured everything out. But they were wrong.

The Rise of Relativity
Around the year 1900, there were two major developments in physics which shattered the (comforting, to some) notion that we’d figured out all of theoretical physics. The first was the dissolution of ether theory – the idea that all motion (including the motion of the Earth) was relative to some absolute frame of reference called the “ether”. The ether was supposed to be some kind of imponderable substance which was postulated to exist throughout all of space. In fact, it was believed that light used the ether as a medium through which to propagate; many scientists disliked the idea that light (commonly understood as an electromagnetic wave) could travel through completely empty space because all waves were believed to have a medium which they had to disturb in order to propagate.

By the late 1800s, two scientists – Albert Michelson and Edward Morley – decided to perform an experiment which would indirectly detect the ether, thus taking it from mere speculation to a firmly established phenomenon. In 1887, they performed their now-famous experiment where they attempted to use a beam of light traveling relative to the Earth’s supposed motion through the ether to detect changes in the speed of the light beam. But they got a surprising result – no matter in which direction they oriented their device (called an interferometer) relative to the direction of Earth’s motion, they got the same result: the speed of light was unchanged. No matter what they did, no matter how many times they ran their experiments, the light beams traveled at the same value: 3×108 meters per second.

This “failed” experiment led to the eventual acceptance that the ether was a fiction.  And not only that, but the speed of light being constant, no matter the relative motion of the observer, led to the foundations of the theory of relativity.  In 1905, Albert Einstein formulated his special theory of relativity, and in 1916 he followed this with his general theory of relativity. You may have heard of general relativity (GR for short), because it is the theory that outlines space & time as woven into a strange fabric known as space-time; in this space-time fabric objects with lots of mass (such as planets, stars, and black holes) warp or dent the fabric. These space-time dents are what Einstein viewed as gravity, and GR now forms our current views on gravitation.

We now use GR to deal with everything from understanding the physics of black holes to dealing with time-delays between ground stations and geosynchronous satellites. Believe it or not, without an understanding of gravity via GR, your GPS receiver wouldn’t work – here’s why not.

Quantum Weirdness
At the beginning of the 20th-century there was another shakeup in the world of physics. This had to do with (among other things) three pesky phenomena the classical physicists of the 19th century were having a hard time explaining: the photoelectric effect, blackbody radiation, and spectral lines. I’ll focus upon blackbody radiation for the purposes of this example, but all three phenomena are explained the same way.

For a long time, scientists knew that when an object heated up it tended to glow. The object would start off feeling warm (which we now know to be infrared radiation), then it would glow red, then orange, and – if it got really hot – white! It was believed that the reason for the white-hot glow of extremely hot objects was due to the emission of all colors of visible light (ROYGBIV) added together – this was confirmed by viewing such objects through a spectrometer. However, there was a big problem – it was believed by the classical physicists that the intensity of the light as a function of wavelength should follow the Rayleigh-Jeans Law (shown below)…

The Rayleigh-Jeans Law as compared to Planck's Formulation of blackbody radiation.

The picture says it all – the data collected from hot objects simply didn’t fit with the classical view of blackbody radiation (this is the “ultraviolet catastrophe” listed above). Physicists were at a loss to explain this contradiction between their theories and observations. Then one day, Max Planck, brought forth a hypothesis which many found to be crazy: Planck proposed that light was not a continuous phenomenon, but instead light was given off in small, discrete bundles of energy called photons. Not only that, he further postulated that the energy of a particular photon of light was directly proportional to its frequency…

E = hf

Planck’s little equation did the trick. It provided a theory which explained the blackbody radiation perfectly, but it rocked the foundations of the physics community. In fact, many people refused to accept the idea, especially when the fuller implications of Planck’s idea (sometimes referred to as the “quantum hypothesis”) were realized.

Over time, many physicists used the new quantum physics to go on to explain all manner of phenomena, and the new theory of quantum mechanics was born. By the 1940s and 50s, quantum mechanics was being used to pave the way for a new kind of technology called computers. And, with the advent of more widespread computer technology – including the desktop computer, the Internet, and the World Wide Web – our society has been changed in ways that no one could have possibly ever predicted, certainly not Max Planck when he was pondering a solution to the ultraviolet catastrophe.

So, the next time you get online, pause for a moment and think about it – the reason you are able to surf the Web on a computer is because over 100 years ago someone was attempting to figure out a purely theoretical problem in physics. The next time you log on, think about

E = hf

In conclusion, I hope this post has given you a better idea of why pure scientific research is useful. It not only helps to address purely theoretical questions of interest to scientists, but the effects upon all of us can be quite profound – from how we view the universe to how our very society functions on a day-to-day basis.

Yes friends, pure science does matter. And don’t you forget it.

2 Responses to “Why Science Matters”

  1. djowtlaw said

    This is an excellent post. As for the original question asked “Why should I care about science?” I honestly think is a very ignorant question because of its ubiquitous beauty and application. I feel that many people feel that it is a belief system rather than facts and observation. There’s nothing to be scared about science other than its utter complexity!

  2. […] bookmarks tagged biology Why Science Matters saved by 1 others     WishingLampPro bookmarked on 01/13/09 | […]

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