PBS Space Time
Perpetual Motion From Negative Mass?
Challenge question: if 1kg of apples is $5 and 2kg is $10, how much is -1kg of apples?
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The Crisis in Cosmology
The hubble constant--the rate of expansion of our universe--has consumed astronomers.
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Secrets of the Cosmic Microwave Background
Secrets of the Cosmic Microwave Background
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The Impossibility of Perpetual Motion Machines
Perhaps the most persistent nonsense in physics: the perpetual motion machine.