José Manuel NievesSEGUIRMadrid Updated: Save Send news by mail electrónicoTu name *
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After twenty long years observing the Universe up to its confines more deep, a collaboration of more than a hundred researchers has just published what they themselves have called “the three-dimensional map largest in the Universe”. And there is no doubt that it is.
The map includes more than two million galaxies and quasars over 11,000 million light years, and is based on observations of the project Sloan Digital Sky Survey (SDSS), an ambitious international collaboration to map the entire observable Universe and, with luck, resolve pass some of the puzzles cosmic plague researchers. In this framework, the results of the project, called BOSS (Baryon Oscillation Spectroscopic Survey), have been published in more than 20 scientific articles and spanning over 500 pages. Up to now, could only determine the distances of the various objects of the Earth, but this latest update of map allows to calculate also the one that exists between two objects either, which has made it possible to build a 3D model.
“we Know pretty well about the ancient history of the Universe -explains Kyle Dawson, of the University of Utah and a member of the collaboration – and also their recent history, but there is a problematic gap in the 11,000 million years in the middle. During the last five years, we have worked to fill that void, and with this we have provided information to help in some of the most important advances in Cosmology during the last decade.”
The “gap” referred to the investigator begins a few billion years after the Big Bang. Scientists can measure the expansion rate of the Universe before the gap thanks to the cosmic microwave background, the residual radiation that remains of the own Big Bang and that it is still possible to detect. And they can also calculate the expansion in recent times by measuring how the distance between the Earth and the nearest galaxies is increasing with time.
But during the larguìsimo intermediate period of 11,000 million years ago, the expansion has been poorly studied, because the light from galaxies that are more than a few hundreds of millions of light years away reaches us very weak. To “fill in” that huge lake, the researchers observed, in addition to galaxies, also burning quasars, are much more luminous and easy to distinguish.
A map spectacular
The map, which is published both in still images as in 3D animation and starts when the Universe was barely 300,000 years old, reveals with all clarity the filaments (rivers of galaxies and the huge voids between them and that define their structure on a large scale. From there, the researchers were able to measure patterns in the distribution of galaxies, which provided several key parameters of the Universe with a precision higher than 1%. The signals of these patterns are shown at the intersections of the image.
In this way the map shows, for example, which makes about 6,000 million years, the expansion of the Universe began to accelerate, and this acceleration has continued, and continues today. “We believe that this acceleration,” explains Julián Bautista, of the british university of Portsmouth and one of the leading scientists of the project BOSS – should be a component invisible Universe which we call dark energy, but we do not understand well how it behaves, that dark energy. It could be, as suggested by Einstein, a cosmological constant, but it is extremely difficult to reconcile with the theories of particle physics”.
Until now, he says the Baptist, “we had some pictures of the beginning, and we could also see how the story ends, but we were missing the biggest part of the movie. Now we can see that part of the History of the Universe and how dark energy became one of its protagonists”.
