Is double slit experiment the only proof for quantum particles' superposition??
you have, among others,
- single particle single slit
- delayed choice quantum eraser
- two-photon interference experiments
- i guess even quantum entanglement
- there are many ways to come up with new experiments/ideas
No, it is just the "textbook" example. If you ask me it is not even a good example since people tend to get hung about the nature of photons etc., which is in no way relevant.
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