Improve UI: add more scientific description

[benbovy]

From Luca's feedback:

The actual main shortcoming was the lack of additional scientific posters to explain what kind of science we actually do with all this.

We could enrich the user-interface with more explanation such as text, images, equations, etc.
To keep the interface clear and tidy, we could use tabs for example (this would allow support for multiple languages EN, DE, etc.).