Task: Text Categorization
Input (English): Alfven Waves occur in these substances, and the Langmuir Probe is used to measure them. The quark-gluon type of these may have been created at Brookhaven RHIC, and these entities are studied in Tokamaks, which attempt to create nuclear fusion. Polar auroras and ball lightning are examples of this type of substance, and this state of matter exists when ionization occurs at extremely high temperatures, . For 10 points, name this substance similar to ionized gas, the "fourth state of matter."
Output (English): Science