TIME APPEARED TO MOVE FIVE TIMES SLOWER IN THE FIRST BILLION YEARS AFTER THE BIG BANG

Time dilation, brought about by the relativistic expansion of space, has resulted in the observed slowing of ‘clocks’ in the early universe

- Tariq Malik

Time has been observed passing more slowly in quasars in the early universe. The observed time dilation comes as a consequence of Einstein’s theory of general relativity combined with the expansion of space. “At its heart, this is another ‘Einstein is right again’ story,” Geraint Lewis, a cosmologist at the University of Sydney, said. Lewis and Brendon Brewer of the University of Auckland are co-authors on a new paper describing the confirmation of time dilation effects in the variability of quasars. A quasar is powered by an accreting supermassive black hole at the heart of an active galaxy. Because the accretion disc around the black hole is relatively small, fluctuations in the light emitted by the quasar can take place in just days. This makes them easier to track.