I Goldstone bosons in description of superfluidity

[Anton Stepennov]

Hello,

I'm trying to understand how the superfluidity is connected with the Lagrangian of the system: in some textbooks (e.g. Antony Zee qft in nutshell) it is stated, that in case, when the excitations in the fluid have energy spectrum linear with momentum , there is a critical velocity, which forbids appearing of these excitation cinematically , and what is not clear, is that beside massless particles with linear energy spectrum there are also kind of "higgs bosons", which appear because of spontaneous symmetry breaking , which are massive so that they can appear at any velocity . How one can show, that the excitation in superfluid are goldstone bosons only?

thanks

 

[MathematicalPhysicist]

Try reading Kardar's or Huang's, perhaps it also appears in Pathria's, not sure.

You should be digging through the literature.
:-)

 

[DrDu]

What symmetry gets broken in the transition to BEC?

 

[DrDu]

See also this review by Yukalov: https://arxiv.org/pdf/1105.4992.pdf