The Language of Physics

"It's all Greek to me", some might say when they glance at a typical first year physics equation sheet. And they'd be right: when our physicists of many centuries ago ran out of Roman symbols (or perhaps when they just wanted prettier symbols), they represented lots of concepts with Greek symbols. For example, here's the equations you'd use to describe the motion of ferris wheel:

Admittedly, it can look rather Greek (though hopefully not bleek). That is, of course, until you start talking about physics. In conversation, physics (especially at the first year level) can be quite accessible. Unlike biology's mitochondria or chemistry's acetylsalicylic acid and other silly words I can't spell, physics tends to use the words of everyday conversation to describe the everyday physical world. For example:

• In physics, your weight is the force of gravity acting on you, but in conversation we might describe an argument as carrying "weight"
• We talk about a leader as having "power"
• Yoda would say, may the "force" be with you
• A kind person has a "magnetic" personality
• We "reflect" on our experiences... especially in teachers college ;)

In some ways, I like this overlap because I think it makes physics less scary - we already know the words (even if we don't yet have a complete understanding of their meaning in physics).  There's a common public perception that physics is a set of equations on a page, having little to do with the "real world". For example, when Eric Mazur spoke here this fall, he told a humorous story of a student who asked him during a test, "Would you like me to answer the way you taught us in class, or the way I normally think about these things?"  The overlap between "physics language" and "everyday language" clearly hasn't been enough to change the perception that physics is separate from real life, but I hope it can be of some help in bridging this gap. I also like this overlap for very practical reasons: my memory barely has room for the words of the everyday English language, so I was quite relieved to find that physics didn't require the huge new vocabulary that comes with a subject like biology.


Sometimes, however, this language overlap leads to misconceptions.  The way we talk about electromagnetic waves - as radio waves, microwaves, infrared, visible light, UV, x-rays, etc in the very different contexts of hearing music in your car, warming food, getting a sunburn, seeing a broken bone - I think this actually hides the pretty physics part: that these are all the same type of wave (electromagnetic waves) simply with different wavelengths. The difference between microwaves and visible light is like the difference between singing low A and singing high C. But our language outside of physics hides pretty connections like this. In a different rather funny example of mismatched physics language, this politician (http://thehill.com/homenews/house/179947-gop-leader-on-jobs-speech-voters-are-sick-of-the-rancor) says he is "focused like a laser"... should we tell him that he's comparing himself to an unfocused slowly diverging beam? 


I find the many contexts of "relativity" to be particularly fun and interesting. In fact, I think our social understanding of relativity can be quite helpful for understanding the physical definition. In physics, we say that quantities we measure like time, mass, length, etc. are relative to the reference frame from which we're viewing the event. Very similarly, in social scenarios, our understanding of an event is relative to our perspective on the event. The concept of relativity can be very helpful for us in understanding why another person, who experiences the same event from a different perspective, might react differently than us. Applying relativity to social scenarios can improve communication and foster better friendships. And understanding relativity socially can help us to understand the concept of relativity in a physics context. 


The concept of relativity can also be very helpful to see our everyday challenges in the light of a bigger picture.  I think we all strive to be the sorts of people who look at situations through the lens (to use another fun physics word) of, "What is really important here?" Probably one of our biggest goals in life is to love people. If we see our everyday challenges relative to these bigger goals, I think all of our lives are just better. 


But just like our politician friend probably should have asked his physics friends for the meaning of "focus" and "laser" in the context where he was speaking, we have to be a bit careful not to apply relativity to places where it doesn't make sense. The speed of light isn't relative; no matter what reference frame you're in when you look at the light, it's always going to be traveling 3 x 10^8  m/s in a vacuum. So we can't simply say "It's all relative" because some things aren't. I often don't know what the 'right answer' is, but I do believe there are some fundamental truths that are constant for everyone. I'm not sure I could be a physicist if I wasn't interested in research that could be generalized beyond myself - things that are true for all of us.