Scientists have examined cosmic radiation left over from the Big Bang to put an end to a long-standing debate over whether the Universe is the same in all directions, or if it’s aligned on some kind of spin axis.
It turns out that in our rapidly expanding Universe, there is no ‘preferred’ direction of expansion – the Universe is expanding in every direction at exactly the same rate. And while that’s good news for our current cosmological models, it’s bad news for Einstein’s famous field equations.
But before we get to the new evidence, let’s run through some background info first.
For years, scientists have argued that the Universe can function in one of two ways: it can either be homogeneous and isotropic – which means it’s fundamentally the same in all directions – or it can be anisotropic, meaning it might look uniform on the outside, but there’s actually a ‘preferred’ direction lurking deep within its fibres.