Scientists decided to test Einstein's theory of relativity in the 1990s. Experts consider this study to be one of the most significant that has ever been carried out. The results of the work can completely change the idea of the universe, because for a long time this theory was considered radical.
The theory challenges one of the most basic ideas of the universe: that the speed of light is fundamental and never changes. This concept "holds together" some of the most important concepts in physics, such as general relativity and how the universe expanded after the Big Bang. However, a radical theory suggests that in fact light in the "young" universe may have traveled much faster than it does today (the speed of light is 186.282 miles). Scientists now hope they can prove that the cosmic microwave background (CMB) is the “afterglow” of radiation that appeared after the Big Bang.
Structures in the Universe, such as galaxies, were formed from small fluctuations (dense matter) in the "young" Universe, which are captured in the CMB. Measurements of these fluctuations can be used to derive the "spectral index" that scientists are still developing. If the new theory is correct and the speed of light was higher immediately after the Big Bang, then the spectral index will receive a speed of 0.96478. Current estimates of the spectral index are already close to this (about 0.968), but scientists are not sure of its accuracy.
The study's lead author, Professor João Mageijo, of Imperial College London, said: “The theory that was first proposed in the late 1990s has now reached a point of maturity. Now we are testing it, so in the future it is possible that Einstein's theory of gravity will be modified. The idea that the speed of light can change was heard earlier, so physicists decided to test it. If this is true, it means that the laws of nature were not always the same as they are today."
Inna Solntseva