Abstract
We investigate constraints on Lorentz invariance violation in the neutrino sector from a joint analysis of big bang nucleosynthesis and the cosmic microwave background. The effect of Lorentz invariance violation during the epoch of big bang nucleosynthesis changes the predicted helium-4 abundance, which influences the power spectrum of the cosmic microwave background at the recombination epoch. In combination with the latest measurement of the primordial helium-4 abundance, the Planck 2015 data of the cosmic microwave background anisotropies give a strong constraint on the deformation parameter since adding the primordial helium measurement breaks the degeneracy between the deformation parameter and the physical dark matter density.
Highlights
Another possible signal of new physics is Lorentz invariance violation in the neutrino sector
We have studied the cosmological constraints on Lorentz invariance violation in the neutrino sector by a joint analysis of cosmic microwave background (CMB) and Big bang nucleosynthesis (BBN)
Instead of fixing the value of the helium-4 abundance, we have applied the BBN prediction of the helium-4 abundance determined by ξ and bh2 to calculate the CMB power spectra
Summary
Another possible signal of new physics is Lorentz invariance violation in the neutrino sector. The Lorentzviolating term affects the evolution of the cosmological background and the behavior of the neutrino perturbations The former changes the expansion rate prior to and during the epoch of photon–baryon decoupling, which alters heights of the first and second peaks of the CMB temperature power spectrum, while the latter alters the shape of the CMB power spectrum by changing neutrino propagation. Lorentz invariance violation affects the CMB power spectrum by changing the BBN-predicted abundance of helium-4. A reasonable way to test Lorentz invariance violation in the neutrino sector with CMB data is to take account of the BBN-predicted helium-4 abundance as a prior rather than fixing the helium-4 abundance. In combination with the latest measurement of the primordial helium-4 abundance, the Planck 2015 data of the CMB anisotropies give a strong constraint on the deformation parameter.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
