Karl Gebhardt

Dark energy has been called the greatest question in all of science. The answer to this mystery could change everything.

UT researchers are leading the charge to understand dark energy, and what they learn could challenge what we thought we knew about the origins of the universe and the principles of physics, even gravity.

The universe has been expanding ever since the big bang. According to the law of gravity, that expansion should slow down and everything should start coming back together. But the universe continues to expand, and at an accelerated rate. The force causing this phenomenon is known as dark energy, and it constitutes more than 70 percent of the universe.

With extensive philanthropic backing and the power of one of the world’s largest optical telescopes, the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) at McDonald Observatory is working to unravel dark energy by probing conditions near the time of the big bang. To do that, UT researchers will build the largest map of the universe ever created, collecting data on a million galaxies, all billions of light-years away.

Karl Gebhardt, the Herman and Joan Suit Professor in Astrophysics, and his colleagues will use the information they find to tweak their models of how the universe began, how it has aged, and how it will end.