This is my favourite room.
A thought experiment costs nothing. No lab, no funding, no equipment. Just a mind willing to follow an idea wherever it goes — even somewhere uncomfortable.
Some of mine:
A 16-year-old riding alongside a light wave
Two lightning bolts and a moving train (simultaneity)
An observer in a sealed box — falling freely, or floating in space?
A clock on a fast rocket vs. one left at home
Each one cracked something open.
Post your thought experiments here. Half-formed ones are welcome. The best ideas often start as questions that feel almost too naive to ask.
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