By Andrew Grant
Matter with negative mass, a seeming impossibility, could actually have existed in the early universe, a new study shows.
A novel solution to Einstein’s equations for gravity permits the existence of negative mass in a rapidly expanding universe like our own, physicists Manu Paranjape and Saoussen Mbarek of the University of Montreal report November 14 in Physical Review D.
Although the research doesn’t prove that such exotic particles once floated around the cosmos, it suggests that negative mass could have played a major role in the epoch called inflation, when the universe ballooned in size just after the Big Bang.