絕對零度點解5係真係零度既

Absolute zero is not zero degree in degree celsius, but in another scale, Kelvin, absolute zero is 0K.

Scientists - especially those who study what happens to things when they become very, very cold - commonly use the Kelvin scale, with temperatures measured in Kelvin (K). This scale uses the same temperature steps as the Celsius scale, but is shifted downward. On this scale, water freezes at 273 K and boils at 373 K. Only on the Kelvin temperature scale does absolute zero actually fall at 0 K.