Towards broken symmetry

Tomorrow's lecture looks at an amazing experiment on the space shuttle that was used to determine one of the critical exponents for the superfluid transition to 6 significant figures. I then introduce the idea of an order parameter and broken symmetry. A nice simple illustration of the latter is the problem of optimising the total lengths of the roads joining four cities at the corner of a square. The solution can be seen in the shape of soap films and in the honeycomb structure found in bee hives.

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