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Title: Goldstone bosons and fluctuating hydrodynamics with dipole and momentum conservation
A<sc>bstract</sc>

We develop a Schwinger-Keldysh effective field theory describing the hydrodynamics of a fluid with conserved charge and dipole moments, together with conserved momentum. The resulting hydrodynamic modes are highly unusual, including sound waves with quadratic (magnon-like) dispersion relation and subdiffusive decay rate. Hydrodynamics itself is unstable below four spatial dimensions. We show that the momentum density is, at leading order, the Goldstone boson for a dipole symmetry which appears spontaneously broken at finite charge density. Unlike an ordinary fluid, the presence or absence of energy conservation qualitatively changes the decay rates of the hydrodynamic modes. This effective field theory naturally couples to curved spacetime and background gauge fields; in the flat spacetime limit, we reproduce the “mixed rank tensor fields” previously coupled to fracton matter.

 
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Award ID(s):
2145544
NSF-PAR ID:
10472283
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Journal of High Energy Physics
Volume:
2023
Issue:
5
ISSN:
1029-8479
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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