Symmetry Breaking And Phase transition 
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*Is every phase transition associated with a symmetry breaking? If yes, what is the symmetry that a gaseous phase have but the liquid phase does not?

*What is the extra symmetry that normal $\bf He$ has but superfluid $\bf He$ does not? Is the symmetry breaking, in this case, a gauge symmetry breaking?
Update Unlike gases, liquids have short-range order. Does it not mean that during the gas-to-liquid transition, the short-range order of liquids breaks the translation symmetry? At least locally?
 A: @VanillaSpinIce
I agree most part of the answer from VanillaSpinIce, instead "The liquid-gas transition is characterized by a first order phase transition but there is no symmetry breaking."
Below the critical point,when a gas-liquid phase transition happens, an interface form between the gas and the liguid(since they have different density), thus a discrete refleciton symmetry (between gas and liquid) is broken.
A: Let me answer your first question: Phase transitions do not necessarily imply a symmetry breaking. This is clear in the example your are mentioning : The liquid-gas transition is characterized by a first order phase transition but there is no symmetry breaking. Indeed, liquid and gas share the same symmetry (translation and rotation invariance) and may be continuously connected in the high temperature/pressure regime. In quantum systems at zero-temperature, one may also encounter transition in between quantum spin-liquid states for which there is also no symmetry breaking. Yet another example is the case of the 2D XY model where there is a continuous phase transition but there is no symmetry breaking (Kosterlitz-Thouless transition).
A: The classical situation with no symmetry breaking is the case of the, so-called, isostructural transitions. The word "isostructural" is misleading, since what is meant is "isosymetric". However, historically the term emerged. There is a number of examples of such transiotions. One is the alpha-alpha' transitions in the hydrogen-metal systems, another is phase separations in fluids and polymer solutions, the coil-globule transition in polymers. Such a transition in a solid phase has been reported for SmS. In the case of the solid phase the crystal lattice changes its volume, but preserves its structure (this gave rise to its name).   
