# You're reading: Posts Tagged: John Baez

### Visual Insight by John Baez

John Baez, the very first maths blogger, has started a new blog called Visual Insight. It’s hosted by the American Mathematical Society and is “a place to share striking images that help explain advanced topics in mathematics.”

So that’ll be nice.

### Not mentioned recently on The Aperiodical

Summer is a busy time for this site’s hard-working triumvirate, so we haven’t been keeping on top of the news as much as we’d like. There’s been some quite interesting news, so here’s a quick round-up of the most important bits:

### Elsevier has made lots more maths articles free to access

Elsevier has just announced in its third open letter to the mathematics community (how much does that sound like a Papal Bull?) that all of the archived material from its “primary mathematics journals” is now free to access.

This completes the process begun in April, when they made everything published after 1995 and before 2008 free. From now on, all articles in the affected journals will be made free to access four years after publication1. The journals involved include Advances in Mathematics, Discrete Mathematics, and the Journal of Algebra. It looks like each journal now has a prominent “Open Archive” section on its homepage, containing a list of recently dispaywalled articles.

1. Sadly, because this is Elsevier, the articles are only available through the user-contemptuous ScienceDirect, so the incidence of heads being banged on desks is likely to go up once people start trying to access it and encountering the site’s maddeningly hyperactive sliding toolbars []

### A Noether Theorem for Markov Processes

• Puzzle 1. Suppose I have a box of jewels. The average value of a jewel in the box is \$10. I randomly pull one out of the box. What’s the probability that its value is at least \$100?

• Puzzle 2. Suppose I have a box full of numbers—they can be arbitrary real numbers. Their average is zero, and their standard deviation is 10. I randomly pull one out. What’s the probability that it’s at least 100?

John Baez and Brendan Fong claim to have answered questions like these, but in a general way that is useful for quantum mechanics:

They’ve written a paper and a blog post.