In such a hectic and confused world as we live in today, it is not difficult to find reasons for wanting to go back to a simpler time. Indeed, every person has regrets that they would change if they could, or certain decisions they wish they acted differently on. There are loved ones they’d give anything to spend another moment with, or simply times they took for granted that they wish they could appreciate to their fullest. It is an inherent part of being human to want to relive and rework the things we think we could have done better. While this might seem simply like groundless fancy, is it possible for time-travel to ever become a physical reality?
…which of the symmetries hold at all? The universe is a curious place and cosmologists endeavour to contain this curiosity into one theory. Or maybe two, if they’re unlucky.
On 11th February 2016 the world rejoiced in the astounding news that the Laser Interferometer Gravitational-Wave Observatory (LIGO) had confirmed the first ever direct observation of gravitational waves, predicted a hundred years ago by Albert Einstein in his theory of general relativity. This is hailed as the breakthrough of the century, like the Holy Grail of scientific discoveries.