# Think of it as…

During the NCAA tournament, they have occasionally played commercials that say, “Think of the NCAA as a marching band,” going through typical activities of a student with the band playing behind the student.  That is, until the trombone knocks over a beaker. “So don’t think of us as a marching band.  Think of us as a spirit squad.”

This is just a priming, however, into what my actual topic was.  Analogy is always fun, and biking has given me a great opportunity to make said analogies.  When I was at UNL and did a lot of biking, I noticed how the trail system could be made to seem like an Interstate highway system.  (Yes indeed!)

For some reason, I wished that there would be signs on the bike trail a-la the Interstate, such as speed limit signs, signs that say the name of the route and the direction, and signs denoting distances to certain exits.  The reason I thought of it was some of the interchanges (!) on the Rock Island and Billy Wolff Trails in Lincoln, such as the ramp to Antelope Park, or the underpasses along Capitol Parkway.

When I was at UNL, I decided to have some fun with this and put up a sign on the Rock Island Trail.  On bike trails, there is no posted speed limit, so I figure to put up a speed limit sign with a non-arbitrarily high speed limit, as shown below:

Yes indeed!  That is $c+\epsilon$, i.e. the speed of light plus some arbitrarily small number (had to do this because when I had made this sign, it was after I had finished a real analysis course).

In my head, I numbered the exits in a way that corresponded to the block number in the primary direction of the trail.  So, for example, the Antelope Park exit on the Rock Island Trail is at about 1700S, and the Rock Island Trail is primarily north-south and ends at O Street (0 N/S), so I called that Exit 17.  And in my head, signs on the trail may have looked like the following example in the style of mile signs on the Interstate (NOTICE: This is a Noah-artist-rendition, and not an actual sign):

My paradigm shifted once I got to Chicago.  Initially, I considered thinking of the trail system in the same way, but once I started taking the L, the limited exits on the trail made me think more of a train line where the exits were full stops and/or flag stops.  This was especially true once I returned to Lincoln for this spring break, as they have installed signs like the following: Other trails in Lincoln had similar signs, of course with different names of trails, and more importantly, different colors.  Naturally, that made me immediately think of the “L,” and as a result, drew up a sign at the “station” in my head.  Naturally, the most salient one was a transfer point to draw the sign.  And for the remainder of the trails, there were different colors corresponding to the different trails, so the concept of the signs at CTA “L” stations appeared in my mind as follows:

“This is Vine.  Transfer to the Maroon Line [MoPac Trail] at Vine.  This is a Blue Line Express to Devaney.”