2024/09/02 by Tema, Seturumane
#FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc)
paper · doi:10.48550/arxiv.2409.02953
The theory of dark matter superfluidity has emerged as a compelling framework, in which the dynamics are governed by a non-relativistic P(X) superfluid Lagrangian that naturally leads to Modified Newtonian Dynamics (MOND)-like behavior when coupled to baryons at galactic scales. Notably, at cosmological scales, this effective description reproduces the standard Λ Cold Dark Matter (ΛCDM) model at the background level, suggesting that cold dark matter may undergo Bose--Einstein condensation at galactic scales. In this work, we extend the non-relativistic formulation by systematically incorporating relativistic corrections within the Friedmann--Lemaître--Robertson--Walker (FLRW) spacetime. We further perform a linear perturbation analysis in this relativistic setting to investigate the evolution of matter density fluctuations. Our results clarify the viability of the superfluid dark matter scenario in explaining large-scale structure formation and identify the parameter regimes in which it remains consistent with current cosmological observations.