Month: July 2011

Introducing Degrees of Freedom

I chose this beautiful artist’s rendition of Latin squres (a precursor of Sudoku) as the logo of my blog. Martin Gardner wrote about them in November 1959. ┬áHis Mathematical Games column was often the cover story. Those were the days (Credit: Emi Kasai/Scientific American).

I started a new math and physics blog called Degrees of Freedom as part of’s new blog network, managed by Bora Zivcovic.

In the introductory post I talk about how I envision the blog and what it will be covering. Hyperlinks throughout the post bring you to past examples of my writing on math and physics.

In the first real post I describe a way of visualizing the cosmic microwave background (also known as the “afterglow of the big bang”) that I am sure is familiar to some cosmologists but that I have never seen written or heard described anywhere.

In the same post, I also point out that the sky used to be red before it turned black. That is also something I have not seen mentioned elsewhere.

I am not retiring though. I will still be posting here, either to add more context to articles I wrote (including posts on Degrees of Freedom itself), or to talk about things that would be off-topic there (including the occasional shameless self promotion).

As always, you can get updates by following me on Twitter at @dcastelvecchi.