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Hello, most of the matter we encounter in everyday life appears in one of three states, solid, liquid, or gas.

Water is one of the few substances that we regularly see in all three forms, as ice, or

water, or as vapor. But it turns out there's much more to matter

than solid liquid and gas. 99% of the visible universe is believed to consist

of matter in a fourth state plasma and there are plenty of common materials such

as glass that doesn't fit easily into these categories. Today scientists are

discovering a variety of new and exotic states of matter, and many of them, such as

liquid crystals, have properties that make them enormously useful to us.

But what are the differences between these states or phases of matter and what is current research telling us about them.

With me to discuss the search of matter are Andrea Seller, Professor of Chemistry at

University of College London, Athene Donald, Professor of Experimental Physics at the University of Cambridge, and

Justin Walk, Professor of Physics and Fellow of Trinity College at the University of Oxford.

Andreseller, I'm just giving a very rough outline, but would you give us a more nuanced idea of what's meant by the phase

States of matter? Well when we think about the states of matter as you've just said of course we immediately start thinking of water

because this idea that you can go from the

solids to the liquid to the gas, you know, it's something that we is drummed into us from childhood.

But when we start thinking about chemistry and physics, we actually now start

thinking a little bit more deeply about this and we tend to use the word phase rather than

state. And this is really to distinguish

the possibility that you might have

...