Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmic Birefringence and Electroweak Axion Dark Energy   Taking the recently reported non-zero rotation angle of the cosmic microwave
background (CMB) linear polarization $\beta=0.35\pm0.14{\rm\, deg}$ 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 $\beta$ implies a
non-trivial $U(1)$ electromagnetic anomaly coefficient ($c_{\gamma}$), 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 $c_{\gamma}$, the model is shown to be able to make
prediction for the current equation of state ($w_{\rm DE,0}$) 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 $w_{\rm DE,0}$ is reduced to
$\mathcal{O}(1)\%$ level ($\delta w=\mathcal{O}(10^{-2})$).

17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th