If it’s 0 degrees today and tomorrow is to be twice as cold, what will tomorrow’s temperature be?
“What is twice as cold as zero?” We receive this ambiguous question occasionally, and with winter now on our doorstep it’s appropriate to take a fresh look. Various answers are possible, but here is one approach: considering the question in terms of heat energy. A substance with a temperature of 0 degrees contains heat—not much, but some. However, a substance chilled to absolute zero (the lowest possible temperature, -459.67 degrees F) contains absolutely no heat energy. If we interpret the meaning of “twice as cold as 0” to be “containing half as much heat energy as at 0,” a substance with a temperature half way between 0 and -459.67 is the answer: -230 degrees.