How much can liquid water be compressed?
I mean the maximum achieved in practice and the maximum achievable in theory.
Say for example one liter of water at 4 degrees Celsius. Can it be compressed to fit in half a liter?
Are there any applications for compressed water?
If you were to put a solar mass of water together, it could compress itself to the density of a white dwarf star, $\approx 10^9 kg/m^3$. Basically an oxygen white dwarf (a known sort of star) with a bit of hydrogen included.
The ocean tries to compress water a LOT at the deepest part, over 700 bars/10,000 psi. It stays a liquid at about 4 degrees centigrade. This shows the incredible property of water - that it is densest as a liquid not a solid. If it did not have this property, then ice would not float, and our oceans would freeze from the bottom up. If you put water in a black hole, it would not decompress back to water when you took it out, because the atoms have been destroyed.
