We exhibit and analyze a homogeneous spacetime whose source is a pure radiation electromagnetic field . It was previously believed that this spacetime is the sole example of a homogeneous pure radiation solution of the Einstein equations which admits no electromagnetic field (see  and references therein). Here we correct this error in the literature by explicitly displaying the electromagnetic source. This result implies that all homogeneous pure radiation spacetimes satisfy the Einstein-Maxwell equations.
PDF and Maple worksheets can be downloaded from the links below.
Torre, Charles G., "A Homogeneous Solution of the Einstein-Maxwell Equations" (2012). Research Vignettes. Paper 1.