I was never very good at arithmetic or math when I was in school. This was rough because my dad was a mathematician. I struggled more, I think, than my parents knew or my teachers knew. Now I know there is a learning disability — discalcula — that makes it difficult for some students to read a number problem. When we got to algebra, I was screwed.
But in 9th grade we had one six-week unit on a different kind of math. I didn’t just love it, I got an A. It was a unit on theoretical math and it included topology. That was completely fascinating to me. Here were bottles that had no inside or outside, maps that couldn’t be drawn (but had been), and the Möbius Strip. I already knew about this wonderful thing because my dad and I had built some.
“Here’s the symbol for infinity, MAK,” said my dad. I loved infinity.
I think my dad must have been happy when I cam home excited about math rather than despairing. I wanted to talk to him about all the cool stuff I’d learned — about Pascals triangle, probability theory, Klein bottles, the whole shebang.
It was our custom to do the Saturday shopping together without my mom. Now I understand it was a way for my dad (who had MS) to enjoy a walk around the grocery store aided by a shopping cart. We had our method. We went up one aisle and down the other. It was an inside joke between us. When my mom was a teacher, she’d assigned the usual fall essay, “How I Spent my Summer Vacation.” Her school was in rural Montana, so she couldn’t have expected much, but one kid wrote. “I hoed beets. I went up one row, and down the other. Up one row and down the other.” He filled the paper with this.
And my mom told this story over and over…
One Saturday my dad and I headed to Bakers (the store). Dad had a list, but we often bought stuff off the list. At the end, it was a race between me and the checker to see if I could keep up with her or even get ahead of her. Back then, prices weren’t scanned, they were punched into the cash register key board.
My dad and I were waiting for the people ahead of us. As the groceries were carried on the conveyor belt, my dad suddenly said, “You know what that is?”
“Most conveyor belts are Möbius Strips.”
I tried to fathom this by imagining a little paper Möbius strip in my mind.
“It has no sides, honey. Remember? By using a Möbius strip as a conveyor belt, no ‘side’ wears out before the other. It wears evenly.”
“Wow.” That this strange stuff was actually useful seemed miraculous to me.
“Still haven’t found a practical use for the Klein Bottle, though,” laughed my dad.