### Podcast: Fibonacci Patterns in Nature

Today on the podcast I'm talking with Matthew Pennybacker, a mathematician who studies patterns in plants. In his most recent work, Pennybacker and his colleague Alan Newel have provided a mathematical description of the beautiful, swirling patterns that we see in sunflower heads.
 Image by Bohringer

Notice that the spirals on the sunflower head go in two directions: clockwise and counterclockwise. The number of spirals going in either direction usually differs on a single flower, and the number of spirals certainly varies from flower to flower; BUT the spirals still follow a regular pattern*: the number of spirals are almost always variables from something called the Fibonacci sequence.

The Fibonacci sequence starts with numbers 1 and 1, and then proceeds as such: each new number is the sum of the last two numbers. So the sequence goes: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89 and so on. Now why on earth would plants want to exhibit such a pattern in the way they organize their seeds? And how does the sunflower know that the seeds are being put in the right order? Listen to the podcast to find out! PLUS you'll hear how this mathematical understanding of plant patterns could actually teach us something about human development, convection in the atmosphere, and hard drives.

*There is also variation in the prevalence of Fibonacci numbers among different species of sunflowers.

### How 4,000 Physicists Gave a Vegas Casino its Worst Week Ever

What happens when several thousand distinguished physicists, researchers, and students descend on the nation’s gambling capital for a conference? The answer is "a bad week for the casino"—but you'd never guess why.

### Ask a Physicist: Phone Flash Sharpie Shock!

Lexie and Xavier, from Orlando, FL want to know: "What's going on in this video ? Our science teacher claims that the pain comes from a small electrical shock, but we believe that this is due to the absorption of light. Please help us resolve this dispute!"

### The Science of Ice Cream: Part One

Even though it's been a warm couple of months already, it's officially summer. A delicious, science-filled way to beat the heat? Making homemade ice cream. (We've since updated this article to include the science behind vegan ice cream. To learn more about ice cream science, check out The Science of Ice Cream, Redux ) Image Credit: St0rmz via Flickr Over at Physics@Home there's an easy recipe for homemade ice cream. But what kind of milk should you use to make ice cream? And do you really need to chill the ice cream base before making it? Why do ice cream recipes always call for salt on ice?