More on the Classical Double Copy in Three Spacetime Dimensions

Understand

It is well-known that General Relativity (GR) in three spacetime dimensions (3D) has no well-defined Newtonian limit.

• Recently, a static solution mimicking the behaviour of the expected Newtonian potential has been found in arXiv:1904.11001 by studying the classical double copy of a point charge in gauge theory.
• This is the first example where the vacuum solution in the gauge theory leads to a non-vacuum solution on the gravity side.
• The resulting energy-momentum tensor was attributed to a free scalar ghost field; however, alternatively, the source can be seen as one resulting from a spacelike perfect fluid.