I Love Halloween!

I love Halloween! It was a bummer that we didn't have many students dress up this year - not even for extra credit! But W had a good joke on Dr. van Howe and his lab UNOLA. Pretty funny!

Dr. van Howe himself dressed up - he thought a Roman would be appropriate for an engineering adviser, since the Romans were such good engineers. He was too shy to wear it to the faculty dining room, so he just wore his Japanese headband - as Karate Kid, I guess.

Well, I didn't have enough sense not to wear my costume to the faculty dining room, so I was explaining relativity to one and all throughout lunch!

What was I explaining? Well, I wasn't just a witch. I was a spacetime graph. At the peak of the hat was an event (me changing my clocks back to standard time tomorrow night). The only things that can effect this events are things that can reach it at the speed of light or less. If you graph all the points that connect to the event at the speed of light or less, you get a cone - the light cone. That's the cone of my hat - the light cone.

Any event outside the light cone cannot affect me changing my clocks, nor be affected by it. The events outside the light cone inhabit a spacetime region called elsewhere. That's the brim of my cap - outside the cone!