# Physics in a nutshell

1. Jan 4, 2013

### flatmaster

Trying to describe physics in as few words as possible for my teacher website. SOme ideas below.

"Physics lets us describe the world around us with math. That's physics in a spherical nutshell"

Physics lets us describe the world around us with math. We go beyond simple arithmetic and use equations, algebra, and calculus to make predictions about how things work in our universe. Whenever possible, we put our models to the ultimate test and perform experiments to temper our predictions.

2. Jan 4, 2013

### Whovian

I'd have to argue that physics isn't really about math, but rather just disproving things.

For instance, we could rephrase Newton's Second Law as "the harder we push, the faster something accelerates." (Though the relationship could be something other than F=ma, it could be F=m*ln(k*a), where k is a constant.) I could imagine someone with absolutely no mathematical background understanding that, so long as they knew what "acceleration" meant.

The point is, mathematics isn't required to describe the Universe, it's just the most convenient way for us to describe it. And the reason for this, I imagine, is because most of our measurements are numerical.

Now, on to disprovability. The heart of all science, physics especially, is that we come up with a theory in some way and try to take experiments to disprove it. For instance, if a box accelerated backwards when we pushed it one way, and our push were the only force acting on it (and it had positive mass,) that would immediately disprove Newton's Second Law. Of course, our replacement would have to explain why all experiments so far agreed with Newton's Second Law, just as GR explained why orbits were so close to those predicted by Newtonian Gravitation.

So the shortest way I can come up with to describe it is:
"Experiment contradicts theory? Bye bye theory!"