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The Kid Should See This

Entropy: How a sandcastle reveals the end of all things

Professor Brian Cox builds sandcastles in the Namib Desert to explain why time travels in one direction. It is a result of a phenomenon called entropy; a law of physics that tells us any system tends towards disorder. 

“Entropy explains why, left to the mercy of the elements, mortar crumbles, glass shatters, and buildings collapse.”

via It’s Okay to Be Smart.