Dr. William Kinney, University at Buffalo - A Sibling Universe?
Albany, NY – In today's Academic Minute, Dr. William Kinney of the University at Buffalo examines the evidences for and against the existence of a sibling universe.
William Kinney is an associate professor in the Department of Physics at the University at Buffalo. His research interests include inflationary cosmology, cosmic microwave background physics, and dark matter, dark energy and the accelerating universe. He holds a Ph.D. from the University of Colorado.
Dr. William Kinney - A Sibling Universe?
Space and time came into being 13.7 billion years ago in an event known as the big bang. As we understand the big bang, the universe should be pretty much the same everywhere, and objects in it should on average move randomly, in all directions. So it came as a surprise in 2008 when a group of researchers led by a NASA scientist reported that clusters of galaxies far apart from one another appeared to be moving in the same direction.
They called this unexpected motion "dark flow," and their findings created an exciting mystery. If things in our universe are moving in a "special" direction aligned with the dark flow, then there is something going on which we did not expect and do not understand. Maybe something bigger than the universe we can see is pulling on our universe. Maybe something else stranger still.
Or maybe not.
My colleagues, De-Chang Dai and Dejan Stojkovic and I recently looked at data from 557 exploding stars called supernovae scattered across the universe. If the dark flow is real, these supernovae should be moving with it. Our results do not match the analysis of the NASA team. We found no evidence that the supernovae share a common motion. Our conclusion is boring in a way because it matches one's expectation for a Big Bang universe.
This is how science is at the frontier: measurements give confusing and apparently conflicting results. The solution is better measurements. It is not yet clear who is right, but better data will tell us.