The universe is expanding 9% faster than previously thought

Measurements taken by the NASA's Hubble Space Telescope reveal the universe is expanding faster than theoretical models predicted. A new paper published in the Astrophysical Journal Letters reveals the universe is expanding 9 percent faster than expected.

This is not the first time astronomers have discovered a discrepancy between actual measurements and the theoretical value of Hubble's supposed constant. The new paper reduces the chance that this discrepancy is a fluke to 1-in-100,000, suggesting there's indeed something wrong with the theoretical models of how our universe supposedly works.

In the new study, Riess's team measures the Hubble constant to a value of 74.03 kilometers per second per megaparsec, give or take 1.42. That's at odds with the best estimates from Planck, a European Space Agency telescope that made the best measurements to date of the cosmic microwave background. Planck's data pegs the Hubble constant at about 67.4 kilometers per second per megaparsec, give or take 0.5. In statistical parlance, the difference between these two results stands at about 4.4 sigma, or 1-in-100,000 odds that the discrepancy is merely a fluke.

“To use an analogy, let’s look at a two-year-old and see how tall they are, and then try to figure out how tall they are going to be when they grow up. Then we could actually wait until they grow up and measure them,” Riess says. “If they far exceed that [extrapolation], we’d have a real mystery on our hands. Something isn’t right in our understanding of how this person grew.”

More at National Geographic.