Revisiting the tension between fast bars and the ?CDM paradigm

The pattern speed with which galactic bars rotate is intimately linked to the amount of dark matter in inner regions their host galaxies. In particular, haloes act slow down via torques exerted through dynamical friction. Observational studies barred galaxies tend find that fast, while hydrodynamical cosmological simulations galaxy formation and evolution $\Lambda$CDM framework have previously found excessively. This has led a growing tension between fast paradigm. this study we revisit issue, using Auriga suite high resolution, magneto-hydrodynamical zoom-in framework, finding remain $z=0$. Auriga, form higher stellar-to-dark ratios are more baryon-dominated than previous simulations; suggests order for massive spiral must lie above commonly used abundance matching relation. While reduces aforementioned rotation $\Lambda$CDM, it accentuates recently reported discrepancy dynamically inferred spirals those from matching. Our results highlight potential bar dynamics constrain models evolution.