What is light? If you’re like me, you’ve been trained to say “photons,” or, “electromagnetic radiation.” Well, there’s a guy who’s been working with the Exploratorium for several decades who can make you see light in a whole different way.

For a detailed “light walk,” you can go to the Light Walk on the Exploratorium website. That’s where the images in this blog post are from.

If you take two go outside on a sunny day and put a hole in a piece of cardboard, and let the dot of sunshine fall on a white screen, you’ll see an upside-down and backwards pinhole image of the sun. The image to the left was made with square holes in a board! You can do the same thing by making a mesh of your fingers — the bright spots on the ground where the sun gets through will be round images of the sun.

What did the hole do? What we did there was to block a bunch of light, and just let through a little bit of light. We let through one image of the sun.

What if we expanded the hole so it’s a slot? We’d see a slot projected on the screen — but with rounded edges. It’s a series of images of the sun, all stacked up together.

What if we took the paper away entirely? The screen looks bright white. That is infinitely many images of the sun.

So sunlight is a bunch of images of the sun, but so many that we can’t distinguish them. It’s too much information. By blocking most of the light, we make it possible to see just one of the images.

One way to convince yourself of this is with an anti-hole. Instead of a piece of paper with a hole in it, use a small scrap of paper (any shape) to block out a small bit of light. What do you see on the screen? A round black shadow. That’s a missing image of the sun. So shadows are missing images.

Definitely check out the link if you find this stuff interesting.

One of the senior artists at the Exploratorium recently asked all the science types at the museum, “Could you tell me why you value art and the artists here?” Here’s what I told her:

The artists at the Exploratorium tickle my brain. The art exhibits at the Exploratorium, as well as the conversations with artists, have had a tangible effect upon my creativity. My mind was humming in my first months here as I was exposed to new representations of things that I had a tendency to think of in an abstract way (equations and theory, for example, or bland “textbook” examples.) I can’t say that being around artists has taught me to *create* things with an aesthetic appeal, but it certainly has opened my vision to seeing things in a new way and to consider aesthetics as an aim in itself. The art at the Exploratorium also opens me up to wonder. It is easy to get lost in the seriousness of science, reading the latest science news or considering detailed questions of why something works. When I walked in and saw the new installation — the one with the lightbulbs whose illumination chases each other around — my mind went a little fizzy and I just stood there and appreciated it. It also reminded me of many things that I know about — neuronal networks, electronic circuitry, persistence of vision. I appreciated it on an aesthetic ground, and it also represented many things in science for me.

Photo was taken by Sebastian Martin at the Liminality exhibition.

I recently heard Margaret Wertheim speak — she’s a pretty famous science writer and commentator. She questioned who we are reaching when we write about science. Only 7% of the US population reads a science magazine, she says. And those people are mostly male, well-educated, and in their mid 40′s, with high income. What about everybody else?

So, she’s recently been writing about science for women’s magazines. The idea is to bring science to where people are, not to make them come to you. And women’s magazines sell well. It’s been a challenge, however, since editors want to do stories about women’s health, and she had to stick to her guns to do real science. She also had to assume the readers had no prior knowledge of science, and keep their interest. It was also very difficult to sell to advertisers, and so said it was important to get sponsorship to write these articles.

A former colleague of mine at the Exploratorium recently published an interview with Margaret. Margaret said some really gutsy things — things that I have often thought but felt they were slightly blasphemous. Like, much of theoretical physics is of no direct benefit to society, and constitutes an immoral use of public funds to satisfy the curiousity of an elite group. She also suggests that science journalists are often a “cheer squad” for science, instead of critically questioning its use and fundamental principles. We shouldn’t dogmatically believe in science any more than we would religion.

Margaret also been working on some crocheting projects with Daina Taimina. They’ve been crocheting hyperbolic geometries, a mathematical structure that has been really hard to visualize before. A lot of marine creatures use hyperbolic geometries because they maximize surface area (which is important for a lot of biological things.) So, they also undertook a project to crochet a beautiful coral reef. You can see that and other projects at the Institute for Figuring, which is the original source for the image above.

Someone said to me recently that their interest in the science of everyday life stems from their natural curiosity, their desire to “poke the world.” I liked that.

My interest in science is totally hedonistic. I like to learn stuff. There are lots of people like me. I think we find it sometimes hard to relate to people who aren’t driven by that curiosity. How do we reach them?

Of course, keeping science concrete and related to life is important. Science is something we do, after all, it’s an action. It’s not a set of static facts, but a method of gathering knowledge about the world.

Bringing science to people where they are — to the public square, to popular magazines, is also important. For example, why can’t I shower after getting a perm? There’s a good chemistry lesson lurking in there!

Other good examples of bringing science to the public square are the work of Jennifer Ouellette, who wrote the popular Physics of the Buffyverse (using Buffy the Vampire Slayer to teach about science). Also, Tim Gay, who taught 1 minute physics lessons during the game breaks at Nebraska football games. What a challenge.