The triple point of any substance is that temperature and pressure at which the material can coexist in all
three phases (solid, liquid and gas) in equilibrium.
Specifically the triple point of water is 273.16 K at 611.2 Pa
Answered by: Ryan Hitch, MPhys Physics, University of Hull
'The mathematician's patterns, like the painter's or the poets, must be beautiful; the ideas, like the colours or the words, must fit together in a harmonious way. Beauty is the first test: there is no permanent place in the world for ugly mathematics.'