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The universe expands so fast we may need new physics to explain it

The universe expands faster than expected, suggesting that astronomers may need to incorporate new physics into their theories of how the cosmos works, a new study report. The revised expansion rate is about 10% faster than predicted by observations of the universe trajectory just after the Big Bang according to the new research. The study also reduces the likelihood that this difference is a coincidence, from 1 to 3,000 to just 1 in 100,000. "This error has increased and has now reached a point that is really impossible to reject as a fluke" study author Adam Riess, a professor of physics and astronomy at Johns Hopkins University in Baltimore, said in a statement . "This is not what we expected," said Riess, who won the Nobel Prize for Physics 201 1 (together with Brian Schmidt and Saul Perlmutter) to show that the expansion of the universe is accelerating at the end of the 1990s. It is unclear what drives this surprising acceleration, but many astronomers rely on a mysterious, repulsive force called dark energy . Universe: Big Bang till now in 10 easy steps This illustration shows the three basic steps astronomers use to calculate how fast the universe expands over time, a value called the Hubble constant. All steps involve building a strong "cosmic distance ladder" by first measuring accurate distances to nearby galaxies and then moving to galaxies farther and farther away. This ladder is a series of measurements of different kinds of astronomical objects with their own…

The universe expands faster than expected, suggesting that astronomers may need to incorporate new physics into their theories of how the cosmos works, a new study report.

The revised expansion rate is about 10% faster than predicted by observations of the universe trajectory just after the Big Bang according to the new research. The study also reduces the likelihood that this difference is a coincidence, from 1 to 3,000 to just 1 in 100,000.

“This error has increased and has now reached a point that is really impossible to reject as a fluke” study author Adam Riess, a professor of physics and astronomy at Johns Hopkins University in Baltimore, said in a statement .

“This is not what we expected,” said Riess, who won the Nobel Prize for Physics 201

1 (together with Brian Schmidt and Saul Perlmutter) to show that the expansion of the universe is accelerating at the end of the 1990s. It is unclear what drives this surprising acceleration, but many astronomers rely on a mysterious, repulsive force called dark energy . Universe: Big Bang till now in 10 easy steps

 This illustration shows the three basic steps astronomers use to calculate how fast the universe expands over time, a value called the Hubble constant. All steps involve building a strong

This illustration shows the three basic steps astronomers use to calculate how fast the universe expands over time, a value called the Hubble constant. All steps involve building a strong “cosmic distance ladder” by first measuring accurate distances to nearby galaxies and then moving to galaxies farther and farther away. This ladder is a series of measurements of different kinds of astronomical objects with their own brightness that researchers can use to calculate distances. [Image:©NASAESAochAFeild(STScI))

In the new study, Riess and his colleagues used Hubble Space Telescope to study 70 Cepheid variable stars in the Large Magellanic Cloud (LMC), one of the Milky Way satellite galaxies. The Cepheid variables are dimmed and illuminated to predictive prices and are therefore “standard candles” that allow astronomers to calculate distances.

(Another type of standard candle, the star explosions known as type 1a supernova, allows researchers to measure distances even further into space. Riess, Schmidt and Perlmutter studies of type 1a supernova led to their Nobel-winning discovery .]

Riess and his team also incorporated observations from the Araucaria Project, a collaboration involving researchers in the United States, Europe and Chile, who studied various LMC binary star systems and noted the fog that occurred when a star went ahead of its neighbor. This work provided additional distance measurements, which helps the study group improve their understanding of Cepgen’s intrinsic brightness.

The researchers used all this information to calculate the current rate of expansion of the universe, a value called Hubble constant after American astronomer Edwin Hubble. The new number is about 46.0 miles (74.03 kilometers) per second per megaparsec; a megaparsec is about 3.26 million light years.

The uncertainty at this number is only 1.9%, the researchers said. It is the lowest uncertainty value so far calculated using this approach – from about 10% in 2001 to 5% in 2009.

However, the expected expansion rate is approximately 41.9 miles (67.4 km) per second per megaparsec . This forecast rate is based on observations made by the Planck satellite of Europe by the cosmic microwave oven – the light from the Big Bang that created the universe for 13.82 billion years ago.

“This is not just two experiments disagree. We measure something fundamentally different,” said Riess.

“One is a measurement of how fast the universe is expanding today as we see it. The second is a prediction based on the early universe’s physics and on measurements of how fast it should expand, “he added.” If these values ​​do not match, there is a very strong probability that we lack something in the cosmological model that connects the two eras. . “

The new study was published today on April 25 in Astrophysical Journal . You can read it for free on the online preprint page arXiv.org

Mike Walls book about the search for alien life, “ Out There ” (Grand Central Publication, 2018, illustrated by Karl Tate ), is out now. Follow him on Twitter @michaeldwall [19659022]. Follow us on Twitter @Spacedotcom or Facebook .


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