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New Hubble data can change the view of space – scientific news



Astronomers accurately measured the distance to the pulsating stars in the nearby galaxy and confirmed that the universe is now expanding faster than the Big Bang echo. The results of "Hubble" measurements that indicate the presence of "new physics" have been published in the Astrophysical Journal, a RIA Novosti report.

According to Adam Riess of Johns Hopkins University, discovery of discrepancies in the value of the HST constant is the most interesting event in cosmology in recent decades. "Its statistical significance has grown steadily, and now it cannot be easily removed as a measurement error. This gap could not have been accidentally discovered in our data," the scientist said.

In 1929, astronomer Edwin Hubble proved that the universe is not at rest, but is gradually expanding and observing the movement of galaxies away from us. At the end of the 20th century, astrophysicists observing supernovae of the first type discovered that it did not spread at a constant rate but with acceleration.

The reason, as scientists believe today, is "dark energy" – a mysterious substance that makes space-time faster and faster.

In June 2016, Nobel laureate Adam Riess and his colleagues discovered this phenomenon to calculate the exact expansion of the universe today using cefheid variable stars in the Milky Way and neighboring galaxies whose distance can be calculated with ultra high precision.

This clarification has produced an extremely unexpected result: two galaxies, separated by a distance of about 3 million light-years, have been shown to fly at about 73 kilometers per second.

This figure was 9% higher than the data obtained using the WMAP and Planck Orbital Telescopes 69 kilometers per second, and cannot be explained by our notions of the nature of dark energy and the mechanism of the birth of the universe.

These discrepancies caused cosmologists to think of two possible ways to explain this anomaly. On the one hand, it is possible that the measurements of Planck or Riesz and his colleagues are faulty or incomplete. On the other hand, it is quite permissible for a third "dark" substance to exist in an early universe other than dark matter and energy, and that it may be unstable and gradually disintegrate.

Facing this problem, Riess and his colleagues began to recheck their own Hubble calculations to observe cepheids in our neighboring galaxy, the Large Magellanic Cloud.

Their main task was to more accurately measure the distance to these stars and prove that their speed was actually higher than assumed by the Big Bang characteristics. NASA recognized the importance of this task and allowed astronomers to directly control the operation of telescopic gyros to enhance image stability.

This was aided by a special Hubble workflow algorithm and its infrared camera, created two years ago by a telescope science team, which allowed scientists to almost immediately target Cepheids in the Large Magellanic Cloud in the same observation cycle. As a result, Riess and his colleagues were able to follow 70 Cepheids immediately without observing from other scientists for several months.

"When Hubble is precisely targeting an object in the universe that uses the familiar stars as a guide, he can only track one Cepheid across his or her path. Instead, we picked up groups of these stars that were so close together. is close to being able to "switch" between them without redirecting the telescope, "explains Stefano Casertano, a member of the Hubble Scientific Team.

This trick has allowed scientists to improve the quality of distance measurements to cepheids almost twice, from 2.5% to 1.3%, which greatly increased the accuracy of the HST constant estimate. Its value did not change to the bottom and even slightly increased and reached a mark of 74 kilometers per second.

Most importantly, these measurements, as Riess points out, achieved a statistical significance of 4.4 sigma. This means that the probability of accidental error in making observations is one in one hundred thousand – so "successful" coincidence in astrophysical view is extremely unlikely. Improving measurement accuracy to one percent, scientist explained this question.

Why is it so, cosmologists and astrophysicists still can't tell. On the one hand, scientists admit that there was another form of "dark energy" in the early universe that grew faster than during the Big Bang. On the other hand, Riess and his colleagues do not rule out the possibility that dark matter can work more closely with visible matter and dark energy than we previously thought.

"Modern cosmological models suggest that the current rate of expansion of the universe must coincide with those calculated by background irradiation. Thus, the presence of irregularities will testify to the existence of new physics. In the past, theoreticians have always told me that it is impossible because Innovation will destroy all their theories and now they think we will have to do it, ”concludes the Nobel laureate.


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