Abstract

Elaborating on an old conjecture by Blackett, we formulate a new conjecture about the neutrality of matter according to which any physical system possesses an active electric charge proportional to its mass. We discuss limits on the conjecture coming from existing laboratory experiments on the neutrality of matter and from the observation of the global surface electric field of the Earth. In a cosmological setting, we show that a cosmic rotation of the Universe is inevitable if our conjecture is true and if the magnetic fields observed today in large-scale gravitationally bounded objects and cosmic voids have a primordial origin. Finally, we discuss the possibility that the angular momentum of spiral galaxies could be a signature of a rotating Universe.