Complex sentence: At the moment, it is not known how the material is produced or if it remains stable without applied pressure, however, there is conjecture that it is possible to produce a new stable state of matter by compressing ultra-cold deuterium in a Rydberg state.
Split into simpler sentences: At the moment, it is not known how the material is produced or if it remains stable without applied pressure. There is conjecture that it is possible to produce a new stable state of matter by compressing ultra-cold deuterium in a Rydberg state.