Hydrodynamics and phases of flocks

Annals of Physics

Volumn 318, Issue 1 SPEC. ISS., 2005, Pages 170-244

  Toner, John ^a   Tu, Yuhai ^b   Ramaswamy, Sriram ^c  

^a UNIVERSITY OF OREGON   (United States)

^b IBM T J WATSON RESEARCH CENTER   (United States)

^c INDIAN INSTITUTE OF SCIENCE   (India)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 20444507542     PISSN: 00034916     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.aop.2005.04.011     Document Type: Review

References (112)

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12. Of course, in a real crystalline ferrogmagnet, crystal symmetry breaking fields make the rotational symmetry of the spins discrete, rather than continuous, since there are only a discrete set of orientations for the spins preferred by the lattice. In flocks, there are no such symmetry breaking fields, so the rotational symmetry is continuous, as it is in the idealized O(n) Heisenberg model of a ferromagnet. Everything we say hereafter about ferromagnetics implicitly refers to this fully rotationally invariant O(n) model.
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