A group of scientists examining the merits of the theory that the speed of light is not constant as previously thought have announced that a new numerical prediction could allow them to experimentally verify it.

Worth noting, this could be termed as a crossroad for science as many theories in Physics are basically based on the idea that the speed of light is always constant and can be measured at roughly 3 x 10^8 meter per second.

variable-speed-of-light
Via NASA

The new theory was proposed by physicist João Magueijo and Niayesh Afshordi. The study, published in the journal Physical Review D, includes an account of the detailed creation of an exact figure on the spectral index (a model that could be potentially used to verify the validity of the theory).

All the structures in the observable Universe today were originally created when fluctuations occurred in the cosmos relatively shortly after the Big Bang. The spectral index is essentially the record of those fluctuations that has now blended into the cosmic microwave background.

The mathematical figure the researchers came up with has a precision of 0.96478 — almost the same as the currently used estimated readings of 0.968 gathered from the cosmic microwave background.

The theory proposing that the speed of light is variable was first proposed in the late 90s. At that time, it was understandably considered as a radical idea. However, now that a numerical method of prediction has been worked out, the controversial theory could finally be put to test.

While the details are pretty complicated, one can “dumb down” the core idea saying that if light speed can indeed vary, it would essentially suggest there was a much higher speed of light during the early Universe, allowing even far away edges to connect.