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The latest measure of the rate of expansion of the Universe is underway, and she confirmed with greater certainty than ever before that we had a real con pickle on our hands. Once again, the result showed that the Universe was growing much faster than it should be based on conditions just after the Big Bang.
The rate of expansion of the Universe called the Hubble Constant and it was incredibly difficult to pin down.
According to Planck satellite data that measured cosmic background noise (the conditions of the early universe, 380,000 years ago only after the Big Bang, the Hubble constant is expected to reach 67.4 kilometers (41.9 miles ) per second per megaparsec, with an uncertainty of less than 1%.
There are several ways to derive the Hubble constant. Edwin Hubble observed the Doppler shift of recessed nebulae, that is, changes in the wavelength of light as the object moved away. But in the decades that followed, our methods were refined.
Today, calculations often involve the use of standard candles such as Cepheid variable stars, whose known brightness allows accurate calculation of distance – and they have consistently returned faster results than Planck.
Last year, for example, a variable calculation of the Hubble constant with a Cepheid gave an expansion rate of 73.5 kilometers (45.6 miles) per second per megaparsec.
This has reduced the possibility that the results are wrong at one in 5,000. We now have a new result that further reduces it.
Using a new method with the Hubble Space Telescope, a team of astronomers has calculated the absolute luminosity of 70 variables of Cepheids in the Great Magellanic Cloud with unparalleled accuracy.
With these data, they derived a new Hubble constant: 74.03 kilometers (46 miles) per second per megaparsec.
It's about 9% faster than estimates based on Planck data. And the probability that the difference is a stroke of luck or an error is now one in 100,000.
"Hubble's tension between the first and the last universe is perhaps the most exciting development in cosmology for decades," said astrophysicist Adam Riess of the Space Telescope Science Institute (STScI) and the Johns Hopkins University.
"This imbalance is growing and has now reached a point that is really impossible to consider as a stroke of luck.This disparity probably could not happen by chance."
Which means that there is something we missed. In a study conducted last year on the Hubble constant using proposed black holes, the acceleration could be the result of an increase in the density of dark energy.
It is thought that this form of mysterious energy constitutes about 70% of the material-energy density of the universe and is currently the most accepted explanation for accelerating the growth of the universe. 39; universe.
Or it may be that dark matter interacts more strongly with normal matter than astronomers have explained.
But it could also mean that, yes, the result is simply not explainable according to the current physics. So, a new strange and brilliant physics might be needed.
"It's not just two experiences at odds," Riess said.
"We measure something fundamentally different, one is a measure of how fast the Universe is developing today, as we see it." The other is a prediction based on the physics of the first universe and on measures of the speed with which it should develop.
"If these values do not match, it becomes very likely that we are missing something in the cosmological model that connects the two eras."
The research of the team was accepted for publication in The astrophysical journal, and is available on arXiv.
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