Introduction to absolute zero
Absolute zero is the lowest temperature in thermodynamics, but only the theoretical lower limit. The unit of the thermodynamic temperature scale is Kelvin (K), and the absolute zero degree is the zero point defined by the Kelvin temperature scale (referred to as Kelvin temperature scale, denoted as K). 0K is approximately equal to minus 273.15 degrees Celsius, which is 0 degrees Kelvin. At this temperature, the object molecules have no kinetic energy and potential energy, and the kinetic potential energy is 0, so the internal energy of the object is 0 at this time.