Einstein's speed of light constant could be proven wrong

Albert Einstein might be known for a great many things, but even the layman might be familiar with at least one thing: E = mc2, the formula for mass-energy equivalence. However, a critical part of that formula might soon be debunked. According to Einstein's physics, light has, does, and always will travel at a constant speed. Some physicists and cosmologists have begun challenging that observation, and may just have gotten closer to proving that the venerable scientist may have been wrong.

It may all sound like the sort of inconsequential things scientists debate about, but the implications of refuting Einstein's physics model has repercussions in how we understand the universe, both now and the past. Specifically, Einstein's theory that light travels at a constant speed underpins the popular Theory of Relativity as well as our models for understanding what happened after the Big Bang.

In particular, Einstein's model presents a puzzle called the "horizon problem". In a nutshell, the constant speed of light wouldn't be able to explain why the universe today, as large as it is, is homogeneous in density, or largely uniform everywhere. If the speed of light were constant right from the beginning of the Big Bang up to the present time where the universe has already expanded, light from the theoretical center wouldn't reach the outer expanse of the universe at the same time. This would result in a non-homogeneous universe, which isn't what we observe today.

In order to solve that horizon problem, scientists like Professor João Magueijo from Imperial College London and Dr Niayesh Afshordi at the Perimeter Institute in Canada theorize that light's speed isn't actually constant. At the beginning of the Big Bang, it would have traveled faster and thus reached from the center to the edge of the universe sooner. As the universe settled down and the expansion slowed down, so did the speed of light. By that time, however, the universe has become mostly uniformly dense.

Of course, that's all theory, but these scientists may have found a way to test that. Scientists have become much better at mapping out the cosmic microwave background (CMB), that is the light history, of the universe. Magueijo and Afshordi have, in turn, used their model to predict a specific number on that "spectral index". In short, if in a few years' time their prediction matches what will actually be observed on the index, then that would confirm their theory as valid and Einstein's constant to be wrong.

Of course, that's not going to change our world, overnight or soon. It will still be challenged by other rival theories about the origin of the universe. And life as we know it will still go on, despite the potential upheaval in the physics and cosmology circles. After all, it's all relative.

SOURCE: Science Daily

Image courtesy of NASA