Before you lose interests to read on (because you don’t know or care about polymer or diffusion or surface or all of them), please picture yourself walking around in your own apartment. Let me ask you where you walk faster, on the kitchen floor tile, or the bedroom carpet? You might wonder what a trivial question – I walk at more or less the same speed! OK. Now you leave your apartment and walk to your lab. I will time you. First, you take the sidewalk, five minutes. Next, evil and omnipotent as I am, I will put a hill on your way. Now you have to climb over it to get to the lab. I won’t be too surprised if it takes you longer.

You might take these scenarios for granted. But can you imagine if you were the size of an ant, the bedroom carpet became endless hills that had to be climbed? Or if you were as tall as maybe Mt. Everest, you wouldn’t even notice there was a hill in your way as you pass it. So, the relative size matters! For polymers moving on a surface, my labmate Janet Wong recently shows us that relative length scale matters too. Long and short polymer chains feel the different roughness for the same surface. One thing I hope to do is to be more quantitative on this.

The story can be more complex. To give you some flavor, when put in a solvent, do polymer chains swim near the surface but not touch it, or they crawl on a surface as if many feet are touching the ground? Is the ground sticky? What do they look like? A messy coil, a stretched long chain, or a rigid rod…

[offscreen]: She is still at the early stage of teaching her polymer pets to behave. It will probably take just a few more years before she really starts to get down to asking these questions. But she is trying.

[Attention! Juan is not a Hispanic male! Her name means “beauty” in Chinese. Well, in her case, sadly, beauty from inside.]

Juan grew up and lived in a small town called Hefei with four million people until she finished her undergrad. Her parents were too busy to put her in preschool where she could have learned discipline. Later in third grade, she was too retarded to calculate the area in geometry, and stubbornly believed 1 kilogram equaled to 100 grams. The fond memory of junior high was about playing pranks on others. Almost dropped out of high school because she couldn’t stop talking in class. Entered her undergrad with the lowest score possible. When she graduated, she was overwhelmed at the thought of moving to a big city, Boston. She felt foolish when she discovered the population there was half a million. Before she moved to Urbana, she switched from a Boston local bank to Bank of America, assuming Bank of America was Bank all over America. Of course she was wrong, again.

However, in the course of life, Juan learned literal discipline is not that important. And, she finally passed third-grade geometry and can google unit conversion if needed. She is now too mature to play pranks or talk in class like she used to. She went on to grad schools after college. She liked Boston in lots of ways. And, believe it or not, she found another local bank in Urbana and happily switched again.

She makes mistakes. But she also learns from those. Ignorance is bliss, and she is still enjoying her life and curious to see what comes next.