The electron electric dipole moment (EDM) d_e is, roughly speaking, a measure of the charge distribution within an electron. Within the standard model of elementary particle physics, such a dipole is predicted to be of smaller than , where e stands for the elementary charge. This article is about the electromagnetic phenomenon. ... Properties The electron is a lightweight fundamental subatomic particle that carries a negative electric charge. ... The Standard Model of Fundamental Particles and Interactions The Standard Model of particle physics is a theory which describes the strong, weak, and electromagnetic fundamental forces, as well as the fundamental particles that make up all matter. ... // The Earths magnetic field, which is approximately a dipole. ... The elementary charge (symbol e or sometimes q) is the electric charge carried by a single proton, or equivalently, the negative of the electric charge carried by a single electron. ...

The existence of a nonzero electron electric dipole moment would imply a violation of both parity invariance and time reversal invariance. Look up Parity in Wiktionary, the free dictionary Parity is a concept of equality of status or functional equivalence. ... Wikipedia does not have an article with this exact name. ...

At present time, experimental searches for the electron electric dipole moment have yielded negative results. The most recent experiment performed at the university of California at Berkeley placed an upper bound on (with a 90% confidence level) of:

Many extensions to the standard model have been proposed in the past two decades. These extensions genereally predict larger values for the electron EDM. For instance, the various technicolor models predict | d_e | that ranges from . Supersymmetric models predict that . In particle physics, supersymmetry is a hypothetical symmetry that relates bosons and fermions. ...

The present experimental limit is therefore close to eliminating some of these theories. Further improvements, or a positive result, would place further limits on which theory is correct.

Ref. B. Regan, E. Commins, S. Schmidt and D. Demille, Phys. Rev. Lett. 88, 071805 (2002).