We formulate a local condition for a nontopological defect to be present. We apply it to electroweak strings and estimate the probability of their existence at the Ginzburg temperature. As a result we find strings long enough to serve for baryon-number generation are unlikely to be produced.

• Received 29 May 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.2166