We can explain 99% of the world with solid, liquid and gas. Add plasma for another 9. Weird stuff like superfuids and supersolids are very unusual. They may be interesting for some aplications in the future. (I guess that when superconductivity was discovered that every major city would have a few superconductivity devices in it. (Google says 50.000 MRI worldwide.))
Even simple solids (specially semiconductors) have a lot of applications that use quantum mechanics, and there are many rabbit holes with more rabbit holes at their bottom. Most of them are explored or partially explored, but there are still many to explore in the future.
We can explain 99% of the world with solid, liquid and gas. Add plasma for another 9. Weird stuff like superfuids and supersolids are very unusual. They may be interesting for some aplications in the future. (I guess that when superconductivity was discovered that every major city would have a few superconductivity devices in it. (Google says 50.000 MRI worldwide.))
Even simple solids (specially semiconductors) have a lot of applications that use quantum mechanics, and there are many rabbit holes with more rabbit holes at their bottom. Most of them are explored or partially explored, but there are still many to explore in the future.