Defects and Homotopy Theory (61)

  • Encircle line defect with curve C
  • n maps C into curve onto projective plane
  • Homotopy Group
is integers mod 2: +-1/2 are equivalent!

More about Order Parameters, Broken Symmetry, and Topology.

This research was paid for by THE US GOVERNMENT by the NSF.

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Sethna's Research 90-94
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Last modified: November 2, 1995

James P. Sethna,

Statistical Mechanics: Entropy, Order Parameters, and Complexity, now available at Oxford University Press (USA, Europe).