Astronomers have watched the distant universe running in slow motion, marking the first time that the weird effect predicted by Einstein more than a century ago has been observed in the early cosmos. The effect, known as time dilation, is driven by the expansion of the universe, as laid out in the scientist’s fundamental exposition of gravity in 1915. But attempts to see time dilation in the very early cosmos by observing extremely bright, distant galaxies called quasars had failed to find the effect. “We have this picture given to us by Einstein and we test it and test it and test it. “In this case, Lewis and collaborators have extended the time dilation studies undertaken previously with supernovae to larger distances,” he said.