Up till now, I've only known of three states of matter - solid, liquid and gas. Now a fourth state of matter has been discovered?
The first hint that a new type of matter may exist came in 1983. In the experiment, electrons moving in the interface between two semiconductors behaved as though they were made up of particles with only a fraction of the electron's charge. This so-called fractional quantum hall effect (FQHE) suggested that electrons may not be elementary particles after all. However, it soon became clear that electrons under certain conditions can congregate in a way that gives them the illusion of having fractional charge - an explanation that earned Laughlin, Horst Störmer and Daniel Tsui the Nobel prize.
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