In this work, we show how states with conserved numbers of dynamical defects(strings, domain walls, etc.) can be understood as possessing generalisedglobal symmetries even when the microscopic origins of these symmetries areunknown. Using this philosophy, we build an effective theory of a$2+1$-dimensional fluid state with two perpendicular sets of immersed elasticline defects. When the number of defects is independently conserved in eachset, then the state possesses two one-form symmetries. Normally, suchviscoelastic states are described as fluids coupled to Goldstone bosonsassociated with spontaneous breaking of translational symmetry caused by theunderlying microscopic structure-the principle feature of which is a transversesound mode. At the linear, non-dissipative level, we verify that our theory,based entirely on symmetry principles, is equivalent to a viscoelastic theory.We then build a simple holographic dual of such a state containing dynamicalgravity and two two-form gauge fields, and use it to study its hydrodynamic andhigher-energy spectral properties characterised by non-hydrodynamic, gappedmodes. Based on the holographic analysis of transverse two-point functions, westudy consistency between low-energy predictions of the bulk theory and theeffective boundary theory. Various new features of the holographic dictionaryare explained in theories with higher-form symmetries, such as themixed-boundary-condition modification of the quasinormal mode prescription thatdepends on the running coupling of the boundary double-trace deformations.Furthermore, we examine details of low- and high-energy parts of the spectrumthat depend on temperature, line defect densities and the renormalisation groupscale (dimensional transmutation).
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