Cosmic string

According to string theory, strings are one-dimensional, but vibrate in all the other dimensions.

A runaway cosmic string is a spatial phenomenon characterized by its extremely narrow width and powerful gravitational fields. They are no wider than a proton yet have gravitational fields as powerful as those of a black hole. Cosmic strings can be detected by the presence of highly accelerated interstellar gases, which serve to outline the string and make it visible to standard sensors, as well as gravitational lensing in the event such gasses are not present.