Can flipping time keep things spinning just right?
Symmetry in quantum mechanics
Can flipping time keep things spinning just right?
Imagine you're spinning a top. If you could reverse time, would the top still spin smoothly?
Time-reversal symmetry means that the laws of physics don't change if time flows backward. So, if you spin a top forward, spinning it backward with time reversed should also work seamlessly.
Example
You spin a top forward, it spins smoothly. If you reverse time, the top spins backward, still spinning smoothly.
Remember this
Time-reversal symmetry ensures the conservation of angular momentum, meaning spinning objects behave consistently forward or backward in time.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
Related concepts
Symmetry (physics)
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Stern–Gerlach experiment
Stern-Gerlach experiment showed quantized angular momentum
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