Has it really been 3 full years since I first started Grey Matters?!? It seems hard to believe, but it's true!

I couldn't even imagine back when I started this that Grey Matters would grow as big as it has, and get as many visitors on a regular basis as it has been getting!

I chose today to start the blog because it's Pi Day (3/14)! Pi Day was first celebrated at San Francisco's Exploratorium back in 1988, and it caught on very quickly. Let's kick off this celebration by checking out the Exploratorium's plans for Pi Day 2008, which includes ideas you can try at home.

Even though, as we've discussed in the past year, you'll never realistically need more than 40 digits of Pi, the challenge of refining Pi to more and more digits is often too much to resist. It's why we do things like memorize hundreds of digits of Pi, and even calculate it out to more than 1.2 trillion digits (1,241,100,000,000 decimal digits of Pi, to be exact)! If you want to explore the digits, you can download pre-calculated digits, or have your computer calculate the digits in real time (Mac OS X version and Windows version).

As fun as pure lists of Pi digits can be, it's much better to get an understanding by putting them in context, as in my aforementioned Visualizing Pi post. You can use Wolfram's new Mathematica Player to examine Pi in context. First, you can easily examine the distribution of digits in the first 10,000 digits of Pi, even in numerous bases. This is great for seeing how long before, say, a 0 appears, or finding the Feynman point. If you've ever wondered why Pi is the value it is, try out this demonstration to see how various shapes relate to their respective circumferences.

However, we're here to celebrate and have fun! Here's an unusual pi-themed Sudoku puzzle to challenge your brain. Instead of a standard 9 by 9 Sudoku using the numbers 1-9, this is a 12 by 12 Sudoku in which each row, column and region (most of which aren't rectangular) must contain the first 12 digits of Pi (3.14159265358). The three 5s two 3s and two 1s add a new dimension of challenge to this puzzle. For a little more passive fun on Mac OS X 10.4 or greater, check out the Pi Viewer and Pi Clock Dashboard widgets. For some more passive Pi fun on any platform, how about the now-classic Hard n Phirm Pi song:

If you're not looking for just the digits, you can go to this video or this website.

Don't forget! It's also Einstein's birthday today! If you'd like to celebrate Einstein's life and have some fun, learn a little bit about his relativity theory over at Al's Relatavistic Adventures and EinsteinLight.

Don't forget to look around Grey Matters and explore all it has to offer, such as the all the Pi posts I've made. Maybe you'll find an entirely new section of the site you didn't know about before! I've enjoyed these three years, and I hope you've enjoyed the ideas and posts I present. Here's to another year of Grey Matters!