Welcome to my math blog. This blog will focus on my research and on topics which happen to come to my mind. Most topics will probably concern Number Theory, in particular Computational Number Theory, but since I'm interested in a wide amount of subjects there will be other posts, too.

## About Me.

My name is Felix Fontein and I'm currently a software developer at
Dybuster AG. Until February 2014, I used to
be a postdoctoral fellow at the University of
Zurich. I'm working in the area of Computational Number Theory, in particular
on arithmetic in global fields, the infrastructure of such fields, computation of
regulators and fundamental units, and related areas. I studied at
University of Oldenburg and at the
University of Zurich, and was a postdoctoral
fellow at the University of Calgary before
going back to Zurich.

## About This Blog.

This blog focusses on my research as well as other mathematical topics which I
am interested in.

## Overview Pages.

## Categories.

- Algebra (21)
- Analysis (7)
- Complex Analysis (1)

- Beautiful Proofs (3)
- Category Theory (1)
- Cryptography (1)
- General (1)
- Linear Algebra (9)
- Number Theory (11)
- Uncategorized (1)

## Recent Posts.

- Partial Fractions.
- The Probability That Two Numbers Are Coprime.
- The Power of the Distributive Law.
- A Cute Identity.
- Solving Certain Linear Systems over the Integers.
- On a Certain Determinant.
- A Strange Inequality.
- Multiplicity of the Determinant.
- Rigorous Arithmetic in the Arakelov Divisor Class Group of a Number Field.
- Inequalities.

## Archives.

2009 (16)
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2010 (8)
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2011 (3)
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2012 (3)
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## Tags.

baby steps Cayley-Hamliton Chinese Remainder Theorem determinant DLP f-representation finite abelian group function field genus giant steps group functors Hasse derivative Hensel's lemma inequality of arithmetic and geometric mean infrastructure Jordan decomposition linear system of equations Leibniz rule Muirhead's inequality n-dimensional number field one-dimensional probability of being coprime Parseval's identity reduction Rao-Blackwell Theorem tensor product topological argument Taylor's formula universal property

## Comments.

Great! Already subscribed to the RSS feed. :-)

Have fun reading :) I fiddled around with the layout the bit, I hope it's not too colorful now... At least, it looks like I'm still able to use CSS a bit... Oh, and I added some more gimmicks to the parser plugins, now it's possible to use a align*-style environment, which helped to fix some too long formulae.

I'm still not sure, where the border of the crocus picture is... I like it. Too colorful perhaps only in contrast to spielwiese ;-)

Have you released the LaTeX-Plugin somewhere? The only problem I encountered is, that Google Reader Gadget is flickering for your mathematical posts. Perhaps because of the many images?

Well, view the background image, then you can see where it repeats ;) I tried several flower picturse, but this one was the only which looked good after making it seamless.

About te Google Reader Gadget: I don't know that one... In Google Reader itself, everything looks fine. At least when all images are loaded. I haven't released the plugin anywhere yet, but if someone is interested I'll send it to him. Are you interested? :)

Of course I am interested! :-)

There are only not too many mathematical blog posts on my blog in the moment.

But perhaps because writing them was so hard up to now. ;-)