Recent 3-7σ detections of parity asymmetry in the observed galaxy distribution have spurred interest in searching for potential signals of primordial parity violation. In this talk, I will explore the possibility of detecting parity-violation in primordial vector fossils using late-time galaxy spins. By leveraging N-body simulations, we employ halo spins as proxies for galaxy spins to examine the persistence of primordial vectorial parity asymmetry at low redshifts. Our method introduces a novel approach to generate initial conditions with significant parity asymmetry while keeping the initial matter power spectrum unchanged. By analyzing the helicity of the initial spin and halo spin vector fields, we detect substantial asymmetry in the initial spin field due to primordial vectorial parity violation, with over 50% of this asymmetry surviving in the late-time halo spin field across a range of scales. I will discuss the cosmological implications of our findings and conclude with prospects using galaxy surveys.
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