The two key references:
[1] The gothic-ℜ theorem of 2008: http://lhc-concern.info/wp-content/uploads/2009/01/fullpreprint.pdf
= O.E. Rossler, Abraham-like return to constant c in general relativity: ℜ theorem demonstrated in Schwarzschild metric. Fractal Spacetime and Noncommutative Geometry in Quantum and High-Energy Physics 2, 1-14 (2012).
[2] The c-global theorem: http://www.ptep-online.com/index_files/2015/PP-43-09.PDF
= O.E. Rossler, The c-global revival in physics. Progress in Physics 11, 340-343 (2015).
June 27, 2016.