November is almost finished and it was a hard cold month here in Scotland. But I don’t want to talk about weather, of course. For this post I have chosen a couple of great mathematicians born in November. Enjoy!

**1. George Boole (2 November 1815) **was an English mathematician. First time I have heard about him was when I did Boolean algebra in my first year of university. I immediately found the topic very interesting, it is just another type of algebra and algebra is my favorite part of mathematics in general. Basically, Boolean algebra is a type of algebra where the variables are the truth values (true = 1 and false = 0). Besides having different variables, we also have different operations: conjunction *and* denoted as ∧, the disjunction *or* denoted as ∨, and the negation *not* denoted as ¬.

Just recently I have discovered that he also worked in differential equations (published two treatises), analysis (there is also a Boole’s identity, which I have to confess I do not know much about, but it seems that it played a very important role in developing the Hilbert transformations) and probability.

I believe that Boolean algebra (his work in symbolic logic) is what made his very famous. This is one of those very important parts of mathematics. Boolean algebra has been fundamental in the development of digital electronics, and is provided for in all modern programming languages. It is also used in set theory and statistics.

**2. Felix Hausdorff (8 November 1868) **was a German mathematician, also considered to be one of the fathers of topology as we know it today. As expected the first time I have heard his name was during a topology course (not the easiest thing I have done). I consider him one of the most incredible mathematicians out there because he played with very complicated things.

His work is not easy to describe in just a couple of words. For this I totally advice you to read the Wikipedia article about him. Also, his life story is very interesting and quite sad.

**3. Jean d’Alembert (17 November 1717) **was a French mathematician. He was also a physicist and music theorist. All of this is easily seen in his work because he combined all 3 disciplines in a very unique way. As an example, the d’Alembert formula helps us obtain solutions to the wave equation. Also, sometimes the wave equation is called d’Alembert’s equation.

Moreover, he played an important role in understanding the fundamental theorem of algebra. As far as I could find out, an error in d’Alembert’s proof regarding this theorem was discovered by Gauss. This is why the theorem is sometimes called d’Alembert or Gauss theorem. For those studying analysis, you have probably heard of the ratio test to check is a series is convergent (this is sometimes called d’Alembert’s test).

**4. August Mobius (17 November 1790) **was a German mathematician. He is very well known for the discovery of the Mobius strip (I believe this does not need an explanation at this point). Most mathematicians or math-lovers have heart, seen and read something about this. Maybe you didn’t know that this was discovered independently by another mathematician (Johann Listing).

There are many things called after him and most of them are related to geometry (Mobius strip, Mobius configuration, Mobius plane, Mobius transformations) and number theory (Mobius transform, Mobius function, Mobius inversion formula). Again, he is one of those mathematicians who played with quite complicated things.

The good thing about all his work is that not just mathematicians and math-lovers have been huge fans of it. Other artists, such as painters, have started to be interested in his work and this gave all of us another reason to love mathematics.

Another great mathematicians is **Benoit Mandelbrot (20 november 1924)** and I have written a whole post about him a while ago.

Hope you enjoyed this post. Let me know if you would like to read more similar ones. Have a great day. You can find me on Facebook, Tumblr, Google+, Twitter and Instagram. I will try to post there as often as possible.

*Don’t forget that maths is everywhere! Enjoy!*