Herfindahl-Hirschman index (or HHI) describing how close the market is to monopolistic market. This tool is used by organizations responsible for the supervision of fair competition (e.g., when considering corporate mergers). This index is obtained using known market shares, \( s_i \in (0,1] \), of competitors in the market:

Ideas present in Thomas Pikkety's book "Capital in the Twenty-First Century" has shaken up the world this summer and now apparently the economic inequality is viewed as a serious problem. But until recently it was a problem interesting only to a few scientists and couple enlightened people. Nick Hanauer was one of the more well-known people who talked about this problem "before it was cool". We invite you to listen to his talk recorded for TED website.

Sierpinski triangle is a fractal named after Polish mathematician Waclaw Sierpinski, who was the first one to describe it in scientific literature (in 1915). The fractal itself is interesting in a sense that it is a two dimensional attractor to couple iterative operations related to triangles (primarily).

In this text we will discuss iterative removal of triangles, shrinking and duplication, chaos game. We will also briefly mention Lindenmayer system, cellular automata and Pascal's triangles.

B. Mandelbrot is probably one of the most well known mathematicians of the second half of the 20th century. As a scientist he was interested in the "strange" fractal geometry. In this TED talk he draws our attention to the naturally occurring complexity we observe everyday, but which is left unnoticed by our eyes. In this talk he briefly and in very simple terms explains the basic concepts of fractal geometry. We invite you to listen to this great man speak.

This text follows up our recent article "Consentaneous Agent-Based and Stochastic Model of the Financial Markets" published in open access interdisciplinary journal PLoS ONE [1]. This article is a result of the ongoing research at the Institute of Theoretical Physics and Astronomy of Vilnius University implementing the ideas of econophysics. Though our research is mostly related to the modeling of return statistics in financial markets implementing ideas from statistical physics, the concepts behind this work and conclusions are related to the much more extensive interdisciplinary understanding of the social and physical sciences. The desire to extend conventional boundaries and achieve more understanding between researchers of physical and social sciences is a strong motivation for us to deal with econophysics.