Abstract:
We point out that an overall electric charge asymmetry in the universe will generate an anisotropy in the cosmic microwave background radiation (CMBR) via the Sach-Wolfe effect. From this, an upper limit on the electric charge asymmetry over a cosmological scale is found using the COBE data, which implies ΔT/T ≤ 10−4 for the CMBR. The same argument constrains the charge of degenerate neutrinos.