US scientists draw controversy as they claim to have fulfilled the decades-long quest to turn hydrogen into a state where it behaves like a metal.
Scientists in the US say they have at last managed to turn hydrogen into a state where it behaves like a metal.
If that is true - and it is a controversial claim - it fulfills a more than 80-year quest to produce what many have said would be a wonder material.
Theory suggests metallic hydrogen could be used to make zero-resistance electrical wiring and super-powerful rocket fuel, among many applications.