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Chapter 01 of 5

Cold Is Not a Thing

Why a fridge moves heat instead of making cold, and how we got there from frozen lakes.

1. The Illusion

   Cold Isn't a Thing

   There is no substance called cold. There is only heat, and the lack of it. A fridge doesn't add cold; it removes heat.

2. The Rule

   Heat Runs Downhill

   Left alone, heat always flows from warmer things to cooler ones. Your coffee never heats up by itself in a cold room.

3. The Trick

   Pumping Heat Uphill

   A fridge moves heat the 'wrong' way, from its cool inside to your warmer kitchen. That takes energy, which is why it hums.