Scientists have conducted a new study which shows that the universe's rate of expansion differs markedly when nearby locations are compared with distant ones.
New research has shown that the universe’s rate of expansion is even odder than scientists had thought, with fresh data showing there to be a discrepancy in this rate when nearby locations were compared with ones that were further away.
Scientists point to this “tension” and suggest that they may need to go back to the drawing board and rethink the physics behind the universe, which also means dark energy and dark matter, as Space has reported.
When looking at new measurements of nearby locations in the universe with the Gaia Space Telescope and Hubble Space Telescope, the rate of expansion was determined to be approximately 45.6 miles per second per megaparsec. However, in the very distant universe, this rate of expansion was found to be a little bit slower at 41.6 miles per second per megaparsec, according to data from the Planck Telescope.
In fact, as scientists continue to delve deeper into measurements like these, they have found that the discrepancy between the rate of expansion in different areas of the universe only continues to grow and get wider.
Adam Riess, a physics and astronomy professor at Johns Hopkins University, described how the new data has left scientists completely puzzled and seeking an explanation.
“At this point, clearly it’s not simply some gross error in any one measurement. It’s as though you predicted how tall a child would become from a growth chart, and then found the adult he or she became greatly exceeded the prediction. We are very perplexed.”
— SPACE.com (@SPACEdotcom) July 13, 2018
The expansion of the universe is something that has accelerated hugely as it continues to grow, for reasons that are not yet fully understood. While some scientists suggest that this sped-up rate of expansion may be related in some way to dark energy and dark matter, others believe that it is also possible that there is a subatomic particle that has not been discovered that could be at the root of this expansion.
To take the newest set of measurements that were studied, the Hubble Space Telescope and Gaia Space Telescope observed Cepheid variables, which are a specific kind of star that can be spotted dimming and brightening in a very predictable manner. In this way, scientists can look at the brightness of the star and accurately gauge their distance in the universe in relation to Earth. With this data, scientists can then extrapolate the universe’s rate of expansion through their measurements.
While Planck data has analyzed how the universe may have looked 360,000 years after it was formed by measuring its ripples, representatives from the Space Telescope Science Institute (STScI) note that its predictions seem vastly different from the most recent measurements that have been taken of the universe’s rate of expansion nearby.
“These measurements, still being assessed, allow scientists to predict how the early universe would likely have evolved into the expansion rate we can measure today. However, those predictions don’t seem to match the new measurements of our nearby contemporary universe.”
The new study showing how the universe’s rate of expansion has been found to vary in different locations has been published in The Astrophysical Journal.
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3 June 2018