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Is Mexican hat technically a double well? It's a single well I guess😅

 5 years ago  

Make it 3D by adding a revolution symmetry around the vertical axis: the double-well becomes a single valley ;)

 5 years ago  

but then you have no rotational symmetry, haven't you?

true. but symmetry for that well is not needed I guess

 5 years ago  

Not at all. It was just a funny thought to start with ;)