Cosmic birefringence and electroweak axion dark energy

Abstract

Taking the recently reported non-zero rotation angle of the cosmic microwave background (CMB) linear polarization β = 0.35±0.14 deg as the hint for a pseudo Nambu-Goldstone boson quintessence dark energy (DE), we study the electroweak (EW) axion quintessence DE model where the axion mass is generated by the EW instantons. We find that the observed value of β implies a non-trivial U (1) electromagnetic anomaly coefficient (cγ), once the current constraint on the DE equation of state is also taken into account. With the aid of the hypothetical high energy structure of the model inspired by the experimentally inferred cγ, the model is shown to be able to make prediction for the current equation of state (wDE,0) of the quintessence DE. This is expected to make our scenario distinguishable in comparison with the cosmological constant (w = −1) and testable in future when the error in the future measurement of wDE,0 is reduced to O(1)% level (δw = O(10 −2 )).

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Introduction to UniversalQCompiler

“…i for all density operators ρ of dimension 2 m [26]. To change the Kraus representation to a Choi state [26] or vice versa, we provide the methods KrausToChoi and ChoiToKraus, respectively.…”