Two scientists challenging Albert Einstein, who believed that the speed of light is a constant. But according to the new study, the speed of light is variable.
Einstein believed that the speed of light-186,282 miles per second (299,792 kilometers per second)-stays the same in every situation, and this meant that time and space could be different in different situations.
The assumption of Einstein and scientists after him that the speed of light is, has been and always will be constant, is the basis of many theories in physics, including Einstein’s Theory of General Relativity.
A constant light-speed, in particular, plays a role in models of what occurred in the very early universe, within seconds of the Big Bang.
Researchers suggesting that the speed of light varies have come up with a numerical prediction that will allow their theory to be tested. All structures in the universe today were created when fluctuations occurred in the early universe. The spectral index is the record of these fluctuations that is now integrated into the cosmic microwave background.
They’ve given the fluctuations in density the early universe, detectable through cosmic background radiation, an exact spectral index number based on the theory that light was much faster in the first seconds following the Big Bang (0.96478, if you’re curious). If future measurements of the index line up with this number, they’ll support the notion that light speed has shifted.
If the variable light speed concept is ever proven right, though, it would change our understanding of how the universe expanded.